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  • General talks will be 12 minutes with 3 minutes for questions.

  • Key talks will be 20 minutes with 5 minutes for questions.

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Ball et al. Floral diversity, disparity and ecological turnover at the Siluro- Devonian boundary: palynological evidence from the Anglo-Welsh Basin, UK

A.C. Ball^a,b and C.H. Wellman^a, J.B. Richardson^b, S. Stukins and P. Kenrick^b

^aSchool of Biosciences, The University of Sheffield, Alfred Denny Building, Western Bank, Sheffield. S10 2TN, U.K.; ^bDept. of Earth Sciences, The Natural History Museum, Cromwell Road, London. SW7 5BD, U.K.

Few other successions have contributed as much to our understanding of late Silurian – Early Devonian land plants as the Lower ‘Old Red Sandstone’ of the Anglo-Welsh Basin, U.K. The nearly continuous fluvial deposits of the basin straddle the Siluro-Devonian boundary, which is a key moment for early land plants. Here, the >40myr long ‘slow-fuse’ evolutionary stasis of primitive cryptospore producing land plants ends with an explosive radiation of tracheophytes and their immediate progenitors as they diversify and dominate terrestrial ecosystems. A comprehensive, appraisal of the dispersed spore record from the latest Ludlow to middle Lochkovian (late Silurian – Early Devonian) of the Anglo-Welsh Basin, building on previous work, has revealed an unprecedented increase in diversity amongst dispersed cryptospores and miospores. Here, we present a quantitative analysis of diversity and disparity (morphological diversity) change amongst the trilete miospores and cryptospores, alongside exploring floral turnover across several, coeval environmentally variable sites, which allows temporal and spatial comparisons of the above. Our findings suggest that not only did trilete spores see immense changes in diversity and disparity across the Siluro-Devonian boundary, but cryptospores also exhibit their own adaptive radiation. The environmental differences between coeval sites may also hint at palaeoecological preferences for certain dispersed spore species and their parent plants.

Keywords: Early Land Plants, diversity, disparity, turnover, Siluro-Devonian, Old Red Sandstone, palaeoecology

Date: August / Agosto 8

Time: 10:00-10:20

Kondas and Filipiak. The Late Givetian palynology of the south-central Poland

M.Kondas^a and P. Filipiak^b

^aInstitute of Earth Scienses, University of Sielsia in Katowice, Będzińska 60 41-200 Sosnowiec, ^bPoland; University of SIlesia, Katowice, Poland

Eight new sections were investigated for palynostratigraphy and palynofacies. The investigated area covers two basins: the Łysogóry-Radom Basin and The Lublin Basin, of south-central Poland. Both basins during the Devonian formed a part of a wide tropical belt of a shelf margin of the Laurussia continent and that gives an opportunity to look into the interval of noticeable palaeoenvironmental changes. Despite the fact that Givetian palynology of Poland is recognized to some extent, there are only few papers that consider the Givetian Taghanic Event from the palynological point of view. The most prominent feature of the palynological Taghanic record was a noticeable decrease in miospores taxonomic diversity. Here the miospore assemblage was represented by 80 taxa and the sections that showed well preserved material follow this low-diversity pattern. The noticeable taxonomic decrease was observed around the Givetian/Frasnian boundary and the dominant genera were small miospores with fine ornamentation (Aneurospora and Geminospora). Beside the miospores, the palynomorph assemblage contained plant remains (cuticles, tracheids), scolecodonts, acritarchs, prasinophytes and first Givetian chitinozoans from the area of Poland. Two sections contained also the oldest known organic tentaculitoids. Palynofacies analysis confirmed the complex palaeoenvironmental situation with the few transgressive-regressive impulses that affected the relatively shallow marine shelf with the high terrestrial input.

Keywords: palynostratigraphy, palynofacies, Middle Devonian, Taghanic

Date: August / Agosto 8

Time: 11:00-11:20

Stephenson. Problems and challenges for Permian palynostratigraphy: a global review

M. H. Stephenson^a

^aGeoscience Consulting, Nottingham UK

Since 2018 when a global review of the Permian (Lucas and Shen, The Permian Timescale, Geological Society, London, Special Publications, 450) and Permian palynostratigraphy (Stephenson, pages 321-347 in the same volume), were carried out, it has been clear that there are certain challenges for Permian biostratigraphy and palynostratigraphy.

Permian palynostratigraphy has been used primarily to correlate coal‐ and hydrocarbon‐bearing rocks within basins and between basins, sometimes at high levels of biostratigraphic resolution. Though these palynostratigraphic schemes related to resource extraction have been very successful, their main shortcoming has been a lack of correlation with schemes outside the basins, coalfields and hydrocarbon fields that they serve, and chiefly a lack of correlation with the international Permian scale. The benefits of a better integrated general palynostratigraphy are very great scientifically because there are numerous events of global scientific interest in the Permian, for example the timing and order of deglaciation events and the detailed characteristics and timing of mass extinction events within the Permian and at the Permian‐Triassic boundary.

Permian palynostratigraphy is strongly affected by phytogeographic provinciality, as predicted by palaeobotanical studies. This makes correlation between regional palynostratigraphic schemes difficult. For these reasons, it is unlikely that a single comprehensive palynostratigraphic scheme for the Permian globally will ever be developed. However local high resolution palynostratigraphic schemes for regions are being linked either by precise assemblage‐level quantitative taxonomic comparison or by the use of single well-characterized palynological taxa that occur across Permian phytogeographical provinces. Such taxa include: Scutasporites spp., Vittatina spp., Weylandites spp., Lueckisporites virkkiae, Otynisporites eotriassicus and Converrucosisporites confluens. These palynological correlations can be facilitated and supplemented with radiometric, magnetostratigraphic, independent faunal, and strontium isotopic dating.

None of the Permian GSSPs involve palynological definitions, which may be problematic given the importance of palynology in correlation in the commercial and academic worlds. However there appear to be taxa that occur at GSSPs or well‐dated boundary sections that could be used to correlate those boundaries. For example Aratrisporites and Otynisporites eotriassicus may be useful to correlate the Permian‐Triassic boundary into non‐marine sections or sections without radiometric dates. Converrucosisporites confluens may be useful in correlating the Carboniferous‐Permian boundary.

The Subcommission for Permian Stratigraphy (ICS) has established a new working group to work towards better correlations between Gondwana and Euramerica in the Permian, and a substantial part of the working group will be concerned with palynology.

References

Stephenson, M H. 2018. Permian palynostratigraphy: a global overview. In: Lucas, S G, and Shen, S Z. (eds) The Permian Timescale. Geological Society, London, Special Publications, 450; 321-347.

Lucas, S G, and Shen, S Z. 2018. (eds) The Permian Timescale. Geological Society, London, Special Publications, 450.

Keywords: Permian; review; palynostratigraphy; correlation

Date: August / Agosto 8

Time: 13:30-13:50

Strother. A new hypothesis proposing a protonematal origin to plant conducting tissue

P. K. Strother^a

^aDepartment of Earth and Environmental Science, Boston College Weston Observatory, Weston, Massachusetts, US.

The origin of land plants represents a major evolutionary advancement during which simple aquatic charophyte algae evolved a de novo developmental program, resulting in a level of complex multicellularity that still characterizes land plants today. One might suppose that the Cambrian to Devonian interval provides a basic stratigraphic record of the evolutionary assembly of the upright axial plant sporophyte, but this is not the case with how most paleobotanists interpret that record. Instead, the present paleobotanical paradigm posits a Precambrian/Cambrian origin of land plants followed by a lengthy missing record after which vascularized plant axes finally appear during the latter half of the Silurian Period. This interpretation of a missing fossil record has been driven by a reluctant acceptance of molecular time-trees as accurate, in combination with the acceptance of claims of the oldest plants and spores.

Here, by assuming the primacy of the fossil record and rejecting the inclusion of rare temporal outliers, I present an evo-devo model of embryophyte assembly, which is consistent with a late arrival to the upright axial sporophyte. This literal interpretation of the fossil record begins with a previously published record of Cambro-Ordovician cryptospores sensu lato and ends with a novel interpretation of the so-called “banded tubes” as tracheid homologs, rather than as fungi as they are most often viewed.

Keywords: nematoclast; Dyadospora; plant meiosis; charophyte; ChIN; protonema; plant development.

Date: August / Agosto 8

Time: 9:40-10:00

Wellman et al. A palynological investigation of the Devonian sequence of Northern Spain

C. H. Wellman^a G. Lopes^a and J. E.A. Marshall^b

^aSchool of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK; ^bOcean & Earth Science, National Oceanography Centre, University of Southampton, Southampton, SO14 3ZH, UK.

Northern Spain (Asturias-Leon-Palencia) hosts an extensive sequence of Devonian rocks that covers most of the Devonian System. It accumulated in the shallow seas surrounding the Armorican Terrane Assemblage (ATA), a development of island located between Laurussia to the north and Gondwana to the south. The sequence is entirely marine and consists of alternating thick limestone units and thick terrigenous units. These are well age-constrained based on the presence of conodonts and invertebrate macrofaunas, and their sedimentology and palaeoenvironments extensively studied. Rich palynomorph assemblages have been recovered from throughout the sequence yielding marine elements (acritarchs, prasinophycean cysts, chitinozoans and scolecodonts) and terrestrial spores. Due to the isolated position of the ATA the palynomorphs are somewhat endemic, but also contain a mixture of recognizable forms of Laurussian and Gondwanan affinity. Most of the global Devonian events can be recognized in the sequence (e.g. Kellwasser and Hangenberg events). This provides an opportunity to study these events in a relatively isolated oceanic setting away from the supercontinents of Laurussia and Gondwana.

Keywords: Devonian; mass extinctions; spores, acritarchs, chitinozoans.

Date: August / Agosto 8

Time: 10:40-11:00

Wheeler et al. Palynology of the Wolfang Basin: implications for floral composition, climate and environment

A. Wheeler^a, U. Heimhofer^a, E. Gow^b, J.S. Esterle^b, R. Littke^c

^a Institute for Geology, Leibniz University Hannover, Callinstraße 30, D-30167 Hannover, Germany; ^b School of Earth and Environmental Sciences, The University of Queensland, QLD 4072, Australia; ^c Energy and Mineral Resources Group (EMR), Institute of Geology and Geochemistry of Petroleum and Coal, Lochnerstr. 4-20, RWTH Aachen University, 52056 Aachen, Germany

The Permian basins of eastern Australia host extensive coal deposits that act as an archive of climate, environment and floras following the end of the Late Palaeozoic Ice Age (LPIA). This study focused on examining palynofloral records from the Wolfang Basin, an isolated half graben containing significant accumulations of coal, adjacent to the foreland Bowen Basin. The main aims of this work were to better constrain the timing of deposition and understand the composition of the basinal floras and the climate and environment in which they grew. Four seams were targeted for sampling: the Wolfang Main and Upper seams as well as the overlying Prospect and Gowrie seams. Samples were collected both from the coals themselves to examine the in-situ peat-forming floras, as well as from mudstone and claystone partings to examine regional floral trends.

Previous studies constrained the Wolfang and Blair Athol basins to the Kungurian, however, new calibrations of the eastern Australian biostratigraphy allow for a reassessment of these ages. The observation of index taxon Praecolpatites sinuosus (APP3.2) would suggest a Kungurian or lower Roadian age for the Wolfang Main and Upper seams whereas the first appearance of Microbaculispora villosa (APP3.3) in the Prospect and Gowrie seams suggests a Roadian age.

Palynofloras in the coals were dominated by diverse spores (Leiotriletes, Granulatisporites, Horriditriletes, Converrucosisporites) and striate bisaccate pollen (Protohaploxypinus) indicative of a peat-forming assemblage dominated by ferns and Glossopterids. Samples from the seam partings included higher abundances of monosaccate (Plicatipollenites, Cannanoropollis) and bisaccate (Triadispora) pollen potentially indicative of conifers and cordaitaleans either occupying non-peat-forming environments or transported from upland areas. One sample featured a particularly high abundance of cavate trilete (Indotriradites) and monolete (Laevigatosporites) spores that is suggestive of groups such as horsetails and lycopsids that grew around lakes and ponds in the periphery of the mire. Algal assemblages comprise of freshwater taxa (Botryococcus, Tetraporina, Peltacystia) and indicate no marine influence.

Keywords: Permian; palynology; Gondwana; Wolfang Basin; Australia; coal

Date: August / Agosto 8

Time: 11:40-12:00

Ellefson et al. The Upper Jurassic - Lower Cretaceous in the Richardson Mountains (Northwest Territories, Canada): palynostratigraphy and palynological insights on the tectono-stratigraphic architecture of the Canadian Arctic mainland

E. Ellefson^a,b,c, J. Galloway ^a,b, M. Bringué^b, S. Hubbard^a and T. Hadlari^b

^aDepartment of Geoscience, University of Calgary, Calgary, Canada; ^bGeological Survey of Canada, Calgary, Canada; ^cDepartment of Geological Science, Stanford University, Stanford, USA

The Sverdrup Basin is a sedimentary basin underlying the Canadian Arctic Archipelago; it currently provides the primary reference framework for the tectono-stratigraphic architecture of the Canadian Arctic. It contains a nearly continuous record of the Mesozoic rifting events that led to the formation of the Arctic Ocean and the associated Amerasia Basin including a sub-Barremian unconformity. The Richardson Mountains, located in northwestern Canada, also contain a nearly continuous sedimentary record of Mesozoic events and are ideally positioned to investigate links between the tectono-stratigraphic evolution of the Sverdrup Basin and adjacent landmasses. Within the Richardson Mountains is a sub-Barremian unconformity, developed during a period of rifting and occurring erosionally at the base of the Mount Goodenough Formation. However, the precise age of the Mount Goodenough Formation, the unconformity, and its relation to polar tectonics remains uncertain.

The aims of this project were to temporally correlate the intra-Mount Goodenough Formation Barremian-aged unconformity in the Richardson Mountains region with the poorly constrained sub-Barremian unconformity in the Sverdrup Basin, and to provide new insight into (1) tectono-stratigraphic linkages with circum-Arctic areas and (2) the development of polar terrestrial ecosystems during a warm interval in Earth’s history. This was accomplished using quantitative palynology to statistically correlate pollen and spore assemblages from the Richardson Mountains to those published from the Sverdrup Basin to test time equivalence and reconstruct paleoenvironmental conditions. Palynoassemblages of the Richardson Mountains (from the Husky and Mount Goodenough formations) were compared to the Sverdrup Basin palynoassemblages (from the Deer Bay and Isachsen formations). Comparison indicated that the Deer Bay Formation and Isachsen Formation are time equivalent to the Husky Formation and Mount Goodenough Formation respectively. Therefore, if the Mount Goodenough Formation and Isachsen Formation consist of time equivalent strata and contain similar palynoassemblages, the sub-Berriman unconformities present in the two formations may be coeval. Paleoenvironmental reconstruction shows that the environment was humid and alternated between warmer and cooler intervals.

Keywords: Canadian Arctic; Jurassic; Cretaceous; biostratigraphy

Date: August / Agosto 8

Time: 16:00-16:20

Stukins. Preliminary observations and implications of a new Bathonian (Middle Jurassic) lagerstätte in Wiltshire, UK. With a focus on the palynology, micropalaeontology and geochemistry

S. Stukins^a

^aDepartment of Earth Sciences, Natural History Museum, London, UK

A new UK Bathonian (Middle Jurassic) lagerstätte has been revealed and was publicised last year as one of the most important Jurassic echinoderm localities in the world. Excavation of the site has produced thousands of exceptionally preserved articulated echinoderms including at least 18 species, belonging to all five extant echinoderm classes. A closer look however, at the range of other fossil groups has shown the exceptional preservation and diversity is not limited to the echinoderms.

I’ll be presenting initial findings from the palynological and microfaunal investigations along with some geochemical analysis in order to help understand the local palaeoenvironment and why this ‘unique’ site exists. Diverse, well-preserved dinocyst assemblages add to a deeper, nutrient-rich environmental interpretation and a ‘mistake’ in processing reveals a fascinating new discovery.

Keywords: Jurassic; Dinocysts; Sporomorphs; Bathonian.

Date: August / Agosto 8

Time: 15:40-16:00

Walley et al. Palynological insights from the Early Jurassic of Lyme Regis, UK

R. Walley^a,b , R. Twitchett^a , J. Whiteside^b and S. Stukins^a

^aNatural History Museum, London, UK; ^bUniversity of Southampton, UK

The Triassic-Jurassic extinction-recovery interval records a period of global climate change; evidenced through carbon isotopes, biomarkers and marine faunal extinctions from a multitude of sites across the globe. Utilising the well-exposed natural laboratory of SW Britain , we investigate the recovery patterns of the early Jurassic. Combining novel palynological, marine invertebrate and geochemical data, spanning the late Rhaetian to the early Sinemurian, we show variable terrestrial input through the early Jurassic.

The terrestrial palynological record at Lyme Regis is dominated by Classopollis spp., Krauselisporites reissingeri and bisaccate pollen, with a concentration of fern spores around the Triassic-Jurassic boundary (Baculatisporites spp., Deltoidospora spp., Trachysporites spp.). The marine palynological record has an abundant assemblage of acritarchs throughout, whilst dinoflagellates are almost wholly represented by Beaumontella langii. These initial findings support similar timings for the recovery of diversity of both palynomorphs and marine invertebrates, which is also apparent in preliminary data from sites in South Wales, UK.

Keywords: Jurassic; Lyme Regis; geochemistry; marine invertebrates.

Date: August / Agosto 8

Time: 16:20-16:40

Carvalho et al. Cretaceous-Eocene dinoflagellate blooms of the James Ross Basin, Antarctic Peninsula

M.A. Carvalho^a, C. R. Amenábar^b, H. Costa^a, V. Abbate^a, G. Santiago¹

^aLaboratório de Paleoecologia Vegetal – LAPAV, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro; ^bInstituto Antártico Argentino, IDEAN-CONICET, Universidad de Buenos Aires.

Studies conducted to date indicate that the records of fossil dinoflagellate blooms are relatively well-known. This natural phenomenon of flowering or proliferation (bloom) of algae usually occurs in response to sudden environmental or climatic changes, leading to a monospecific or few-species assemblages. Some dinoflagellate bloom events, evidenced by their cysts (dinocysts), have been recognized in Antarctica in both Cretaceous and Cenozoic strata. In this preliminary study, five blooms events are characterized, three of them identified from material collected in the James Ross Basin, Antarctic Peninsula (Cretaceous and Eocene) while the remaining two were obtained from the literature (late Maastrichtian and K/Pg boundary). In the Santa Marta Formation (lower Santonian) outcropping on James Ross Island, a bloom of Odontochitina porifera was recorded, reaching 80% of the marine assemblage (92 cysts in total). This bloom matches with the lowest values of continental-derived elements (spores, pollen grains and phytoclasts), which indicates a marine environment far from terrigenous sources. In the Snow Hill Island Formation (late Campanian - early Maastrichtian) cropping out on James Ross and Snow Hill Islands, two peaks of abundance of Impletosphaeridium clavus were identified (73% and 31% of the marine assemblage, respectively), which would have been occurred in response to cold pulses during the Cretaceous, however, without the development of sea ice cover. Likewise, the bloom of Impletosphaeridium clavus (99% of the marine association) in a section of the López de Bertodano Formation (late Maastrichtian) on Marambio Island (Seymour) was reported in the literature associated with the presence of seasonal sea ice and a stratified water column. In the same section, a bloom of different Manumiella species (68% of cysts) was recognized. This genus is characteristic of coastal and shallow-marine environments and could indicate short-term regressions and/or an oceanic cooling that occurred just before the Late Cretaceous massive extinction (K/Pg boundary). Finally, the proliferation of Impletosphaeridium clavus together with Manumiella could be due to the combination of cold and nutrient-rich surface waters that would have favored the increase of both taxa. For the early Paleocene (Danian), the literature indicates an increase in Senegalinium obscurum (23% of the cysts) in the Sobral Formation near the base of a glauconite-rich level, which helps to identify the K/Pg boundary in Marambio Island (Seymour). In addition, Palaeoperidinium pyrophorum was recorded in this same formation, in intervals that show a conspicuous increase in abundance. Finally, in the La Meseta Formation (middle-late Eocene), in the Valle de las Focas and Acantilados I (or Telm 1) allomembers, the bloom is attributed to the dinoflagellate or acritarch species Enigmadinium cylindrifloriferum, which represents more than 90% of the marine assemblage (~150 cysts). Previous work associates the abundance of this species with a shallow and stressful marine environment, interpreted as an outer part of a wave-dominated estuary. Evidently, the causes of the dinoflagellate blooms are diverse, but they are constantly repeated throughout the Mesozoic and Cenozoic of Antarctica. These blooms are manifested mainly as peridinoid cysts (Manumiella, Senegalinium, Palaeoperidinium) and, somewhat, as gonyaulacoid forms (Odontochitina porifera, Impletosphaeridum, and possibly Enigmadinium). Peridinoid blooms mark bioevents, some of which are globally recognized (e.g., Manumiella spike). [CNPq/PROANTAR 442765/2018-5]

Carvalho et al. Floraciones de dinoflagelados del Cretácico- Eoceno de la cuenca del James Ross, Península Antártica

M.A. Carvalho^a, C. R. Amenábar^b, H. Costa^a, V. Abbate^a, G. Santiago¹

^aLaboratório de Paleoecologia Vegetal – LAPAV, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro; ^bInstituto Antártico Argentino, IDEAN-CONICET, Universidad de Buenos Aires

Los estudios realizados hasta el momento indican que los registros de floraciones de dinoflagelados fósiles son relativamente bien conocidos. Este fenómeno natural de floración o proliferación (bloom, en inglés) de algas suele ocurrir en respuesta a bruscos cambios ambientales o climáticos, dando lugar a una asociación monoespecífica o con escasas especies. En la Antártida se han reconocido algunos eventos de floración de dinoflagelados, evidenciados por sus quistes, tanto en estratos del Cretácico como del Cenozoico. En este estudio preliminar se caracterizan 5 eventos de floración, siendo 3 de ellos identificados en material recolectado en la Cuenca James Ross, Península Antártica (Cretácico y Eoceno) mientras que los 2 restantes fueron obtenidos de la literatura (Maastrichtiano tardío y Maastrichtiano/Daniano o límite K/Pg). En la Formación Santa Marta (Santoniano inferior) aflorante en la Isla James Ross, se registró una floración de Odontochitina porífera, alcanzando el 80% de la asociación marina (92 quistes en total). Esta proliferación coincide con los valores más bajos de elementos de origen continental (esporas, granos de polen y fitoclastos), lo que indica un ambiente marino alejado de las fuentes terrígenas. En los estratos de la Formación Snow Hill Island (Campaniano superior - Maastricthiano inferior) reconocidos en las islas James Ross y Snow Hill, se identificaron dos picos de abundancia de Impletosphaeridium clavus (73% y 31% de la asociación marina, respectivamente), que se habrían producido como respuesta a pulsos fríos durante el Cretácico, sin desarrollo de cubierta de hielo marino. Asimismo, en la bibliografía se informó la proliferación de Impletosphaeridium clavus (99% de la asociación marina) de una sección de la Formación López de Bertodano (Maastrichtiano tardío) en la isla Marambio (Seymour), y se la asoció a la presencia de hielo marino estacional y a una columna de agua estratificada. En esta misma sección se reconoció una floración de distintas especies de Manumiella (68% de los quistes). Este género es característico de ambientes marinos costeros y de plataforma interna y podría indicar regresiones de corto plazo y/o un enfriamiento oceánico ocurrido justo antes de la gran extinción de finales del Cretácico (límite K/Pg). Por último, la proliferación conjunta de Impletosphaeridium clavus y Manumiella podría deberse a la combinación de aguas superficiales frías y ricas en nutrientes que habrían favorecido el aumento de los taxones. Para el Paleoceno temprano (Daniano), la literatura indica que la Formación Sobral registra un aumento de Senegalinium obscurum (23% de los quistes) cerca de la base de un nivel rico en glauconita, lo que ayuda a identificar el límite K/Pg en la isla Marambio. Además, en esta misma formación se registró Palaeoperidinium pyrophorum, en intervalos que presentan en gran número. Finalmente, en la Formación La Meseta (Eoceno medio-tardío), en los alomiembros Valle de las Focas y Acantilados I (o Telm 1), la floración se atribuye a la especie de dinoflagelado o acritarca Enigmadinium cylindrifloriferum, que representa más del 90% de la asociación marina (~150 quistes). Trabajos previos asocian la abundancia de esta especie a un ambiente marino poco profundo y estresante, interpretado como la parte externa de un estuario dominado por oleaje. Es evidente que las causas de las floraciones son variadas, pero se repiten de forma constante a lo largo del Mesozoico y Cenozoico de Antártida. Estas proliferaiciones se manifiestan principalmente como quistes peridinoides (Manumiella, Senegalinium, Palaeoperidinium) y, en menor medida, como formas gonyaulacoides (Odontochitina porifera, Impletosphaeridum y posiblemente Enigmadinium). Las floraciones de peridinoides marcan bioeventos, algunos de los cuales son reconocidos a nivel mundial (por ejemplo, el pico de Manumiella o “Manumiella spike”).

[CNPq/Universal 439004/2018-7] 1 Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro. 2 Instituto Antártico Argentino, IDEAN-CONICET, Universidad de Buenos Aires. 3 Programa de Pós-Graduação em Geociências (Patrimônio Geopaleontológico), Museu Nacional, Universidade Federal do Rio de Janeiro. 4 Programa de Pós-Graduação em Geologia, Instituto de Geociências, Universidade Federal do Rio de Janeiro.

Date: August / Agosto 9

Time: 13:50-14:20

Gravendyck et al. Early angiosperms-how far can we reliably go back in the pollen record?

J. Gravendyck^a, J.B. Riding^b, R. Coimbra^c, U. Heimhofer^a

^aInstitute for Geology, Leibniz University Hannover, Hannover, Germany; ^bBritish Geological Survey, Keyworth, Nottingham, UK; ^c Department of Geoscienses, University of Aveiro, Portugal

The timing of the origins of angiosperms is a long-standing topic of debate in plant evolution. Different disciplines and approaches provide highly variable age estimates. It is generally accepted, that early macro- and mesofossils showing unequivocal angiosperm features occur in Early Aptian deposits. The oldest widely accepted fossilized flowers and reproductive structures are from the Torres Vedras mesoflora and have been found within continental strata in the Lusitanian Basin tentatively assigned to Late Barremian ‒ Early Aptian. Workers employing palynology, i.e. the extremely durable, abundant, and widespread pollen record, have suggested much earlier, but highly disputed ages. To date it remains questionable how far back pollen with unequivocally angiospermous features can push back the age for (early) angiosperms.

Here we review existing challenges in the study of palynological records of early angiospermous pollen. Additionally, we present new ‘early records’ from pre-Aptian coastal marine strata from the Lusitanian Basin of Portugal that are known for their excellent pollen preservation from previous studies. Employing chemo- and biostratigraphy we aim to provide a refined stratigraphic framework for existing and newly studied sections to improve our temporal understanding of subsequent palynological findings. Further we document challenges and solutions to finding the extremely rare angiosperm pollen and illustrate new preliminary finds of early angiosperms, especially triaperturate pollen, which suggest the presence of eudicots.

Keywords: early angiosperms; angiosperm evolution; stratigraphy; Lusitanian Basin, Barremian

Date: August / Agosto 9

Time: 14:20-14:40

Nuñez Otaño et al. Testing deep-time fungi and algae as proxies in palaeoecological analysis: A case study of a Maastrichtian flora from Patagonia, Argentina

N. B. Nuñez Otaño^a,b, E. V. Pérez-Pincheira^a, M. Llorens^c,b

^a Laboratorio de Geología de Llanuras. Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante; CICYTTP (CONICET- Prov. ER- UADER), Argentina; ^b CONICET (National Scientific and Technical Research Council), Argentina; ^c Laboratorio de Palinología y Laboratorio de Botánica de la FCNyCS (Sede Trelew) de la UNPSJB.

corresponding author: noeliabnunez@gmail.com

Using form-taxa names in deep-time studies and modern taxa names in quaternary studies is a common practice, particularly for fungi. In recent discussions about how to designate NPP taxa, researchers are reaching a consensus to follow modern taxonomic schemes whenever possible. The main goal of this research work is to assign modern affinities to fossil fungi and algae from Puntudo Chico Formation (Campanian?-Maastrichtian) of basin Cañadón Asfalto, Chubut Province, Argentina. Also, testing how useful will be to assign modern taxa names, specially to these geologically old fossil fungi avoiding form-taxa designations when those species have no stratigraphic values but valuable paleoecological information. The studied samples (n = 6, NF 1-6) came from a small profile of grey-brown limestone and claystone, and those facies could represent a floodplain environment. These samples have micro and mesofossils, abundant palynomorphs like algae, fungi, spores of bryophytes, lycophytes, and Monilophyta, and pollen grains of conifers (Araucariaceae, Cheirolepidiaceae, and Podocarpaceae), cycads (Cycadopites sp.) and angiosperms (i.e., Arecaceae, Liliaceae, Proteaceae) typical of a continental association of an open forest with a clear dominance of angiosperms. After this study, algae were found in the 6 samples with a total of 12 taxa mainly from shallow nutrient-rich freshwater environments (Botryococcus, Lecaniella, Leiosphaeridia, Ovoidites spp., and Pediastrum). A total of 12 fungal taxa were identified in 4 out of the 6 samples (cf. Dyctiosporium, cf. Endophragmiella, cf. Monodyctis, cf. Sporidesmium, cf. Taeoniella, among others). Modern ecological requirements of the NPPs identified lead us to conclude this study site was a woody forest, with an understory of herbaceous angiosperm, and after the register of, for example cf. Endophragmiella and cf. Monodictys sp., indicate the presence of lichens as a fungal substrate. Also, the presence of the fungal genus cf. Entorrhiza could indicate the presence of marsh vegetation in one of the samples (NF 2). The level water fluctuation can be notice by the distribution of algae taxa, along with the presence of some fungal taxa found in a freshwater setting with temperate to tropical climate. This study highlights the importance of designate NPPs in deep time studies using modern taxonomic schemes and particularly for fossil fungi linking form-taxa names with modern fungal genera along with their ecological requirements (trophic mode, guild, substrate preferences, climatic range, etc) allowing us to test fungi as valuable proxies for paleoenvironmental reconstructions despite how old the sediments are.

Keywords: Paleomycology; Modern fungal ecology; NPP; Algae; Deep time; Maastrichtian; Paleoenvironment.

Evaluación del uso de hongos y algas como indicadores paleoecológicos: Un caso de estudio en una flora del Maastrichtiano de Patagonia, Argentina

N. B. Nuñez Otaño^a,b, E. V. Pérez-Pincheira^a, M. Llorens^c,b

^a Laboratorio de Geología de Llanuras. Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante; CICYTTP (CONICET- Prov. ER- UADER), Argentina; ^b CONICET (National Scientific and Technical Research Council), Argentina; ^c Laboratorio de Palinología y Laboratorio de Botánica de la FCNyCS (Sede Trelew) de la UNPSJB.

corresponding author: noeliabnunez@gmail.com

El uso de morfogéneros en estudios palinológicos es una práctica común en muestras desde el Devónico al Neógeno y la aplicación de nombres modernos a distintos taxones se aplica en estudios cuaternarios, particularmente para los hongos. En discusiones recientes sobre cómo designar taxones de palinomorfos no-polínicos (PNP), los investigadores han llegado a un consenso para seguir los esquemas taxonómicos modernos, siempre que sea posible. El objetivo principal de este trabajo de investigación es asignar afinidades modernas a hongos y algas fósiles de la Formación Puntudo Chico (¿Campaniano?-Maastrichtiano) de la cuenca Cañadón Asfalto, Provincia de Chubut, Argentina. Además, evaluar la utilidad de asignar nombres de taxones modernos a hongos fósiles pre-cuaternarios evitando las designaciones de morfogéneros, dado que no tienen valor estratigráfico, pero sí información paleoecológica valiosa. Las muestras estudiadas (n = 6, NF 1-6) proceden de un pequeño perfil de limolitas y arcillitas de color marrón grisáceo, las facies podrían representar a un ambiente de llanura aluvial. Dichas muestras contienen micro y mesofósiles, abundantes palinomorfos tales como algas, hongos, esporas de briofitos, licofitos y Monilophyta, y granos de polen de coníferas (Araucariaceae, Cheirolepidiaceae y Podocarpaceae), cycas (Cycadopites sp.) y angiospermas (i.e., Arecaceae, Liliaceae, Proteaceae) propias de una asociación continental de bosque abierto con clara dominancia de angiospermas. En este estudio, se encontraron restos algales en las 6 muestras con un total de 12 taxones principalmente de ambientes de agua dulce, poco profundos, ricos en nutrientes (Botryococcus, Lecaniella, Leiosphaeridia, Ovoidites spp. y Pediastrum). Se identificaron un total de 12 taxones fúngicos en 4 de las 6 muestras (cf. Dyctiosporium, cf. Endophragmiella, cf. Monodyctis, cf. Sporidesmium, cf. Taeoniella, entre otros). Los requisitos ecológicos de estos PNPs identificados permiten interpretar, que el sitio de estudio era un bosque con un sotobosque con angiospermas herbáceas, y el registro de taxones por ejemplo cf. Endophragmiella y cf. Monodictys sp. nos indicaría la presencia de líquenes. Asimismo, el registro del género cf. Entorrhiza podría indicar la presencia de vegetación palustre en una de las muestras (NF 2). La fluctuación del nivel del agua se puede notar por la distribución de taxones de algas, junto con la presencia de algunos taxones de hongos que se encuentran en cercanía de cuerpos agua dulce con clima templado a tropical. Este estudio destaca la importancia de designar PNPs en estudios pre-cuaternarios utilizando esquemas taxonómicos modernos y particularmente para hongos fósiles, y de esta forma vincular esos taxones con sus requisitos ecológicos actuales (modo trófico, gremio, preferencias de sustrato, rango climático, etc.) comprobando así que los hongos son importantes para las reconstrucciones paleoambientales a pesar de la antigüedad de los sedimentos.

Palabras clave: Paleomicología; Ecología fúngica actual; NPP; Algas; pre-cuaternario; Maastrichtiano; Paleoambiente.

Date: August / Agosto 9

Time: 16:00-16:20

Paez et al. Acme zones of dinoflagellate cysts in the Cretaceous of Colombia: A harmful algal bloom for every occasion?

Manuel Paez-Reyes^a,b, Damian Cardenas^c, German Bonilla^a,d, Duvan García^d

^a Servicio Geológico de Colombia, Bogotá, Colombia; ^bUniversidad EAFIT, Departamento de Geología, Medellin, Colombia; ^cInstituto Colombiano del Petróleo-ECOPETROL, Piedecuesta, Colombia; ^dINCLAY Geología Especializada, Bogotá, Colombia

Maximum abundances of particular dinoflagellate cysts are common in the Cretaceous sequence of Colombia. These events have been explained as the bloom of dinoflagellates in response to the upwelling of nutrient-rich waters or the eutrophication of surficial waters induced by enhanced input of nutrients from the continent. In both cases, it has been assumed that the acme zones of dinoflagellate cysts represent the record of harmful algal blooms. This hypothesis, however, has not been properly tested using palynology in tandem with other geological data (i.e., sedimentology, geochemistry, and other fossil groups). In this work, we present three cases in which palynology is studied along with other proxies aiming to decipher the mechanism that explains each acme zone. The first example corresponds to the Aptian-Albian boundary. During this transition, a bloom of Cribroperidinium and Palaeohystrichophora is commonly found in Colombia. This event is better explained by a rise in the sea level as the acme zone coincides with a maximum flooding surface that is supported by a minimum in the content of elements associated with detrital minerals and the presence of limestones overlying siliceous mudstones. A second example corresponds to a bloom of Subtilisphaera/Palaeohystrichophora at the dawn of the Cenomanian-Turonian oceanic anoxic event 2 (OAE2). In this case, the peak of superabundance corresponds with an increase of terrestrial palynomorphs and the Ti/Al and K/Al ratios indicating ocean fertilization driven by an enhanced influx of nutrients from the continent. Finally, cherts, phosphorites, and packstones of fish remains and pellets of Campanian age are widespread in eastern and central Colombia. These rocks yield a characteristic palynological assemblage dominated by the tropical genera Senegalinium and Andalusiella. The rock type, the high contents of Si, P, and other micronutrients, and the high abundances of peridinioid dinocysts are all consistent with an overturn of the water column induced by seasonal upwelling that resulted in a harmful algal bloom and massive fish mortality. Our results caution against interpreting every acme zone of dinoflagellates as the result of eutrophication of the water column and a harmful algal bloom as this interpretation is simplistic and not necessarily correct.

Keywords: harmful algal blooms; Cretaceous; acme zones.

Date: August / Agosto 9

Time: 14:40-15:00

Samant. Aquatic and semiaquatic lacustrine flora from Late Cretaceous-Early Paleocene Deccan volcanic associated sedimentary beds: implications in assessing Paleoclimate and depositional environment.

Bandana Samant^a

^aDepartment of Geology, Law College Square, RTM Nagpur University, Nagpur, Maharashtra -440001, India

Distinctly diverse aquatic and semiaquatic flora has been recorded from the Deccan volcanic associated infra and intertrappean beds across the Cretaceous-Paleogene. The floral communities are represented by algal remains of, Chlorophyceae, Cyanophyceae and Zygnemataceae. Bryophytes are represented by Anthocerotopsida, Bryopsida, and Hepaticopsida. Aquatic ferns Salviniaceae (Azolla), Marsileaceae (Crybelosporites and Gabonisporis) are the most dominating group. Other pteridophytes such as Achrostichum (Pteridaceae), Equisetum, Isoetes, Selaginella, and Thayeriorhizomoxylon chandraii (Polypodiaceae) are scarcely represented in Deccan volcanic province. Deccan aquatic and semiaquatic angiosperms record is not taxonomically very diverse but they are represented by some of the important taxa such as Nymphyocaulon (Nymphaeaceae), Aerophyllites (Typhaceae), Similacites, Eriospermocormus, Liliaceae (Liliaceae), Acanthus (Acanthaceae), Eichhnornia (Pontedermiaceae) and Sparganiaceaepollenites (Sparganiaceae/Typhaceae),

Abundant fossil remains of thermophilic vegetation like palms, macrophytes and microfloral remains of algae (Oedogonium), Salviniaceae (Azolla), Marsileaceae as well as paleosol indicate frost free, warm, humid tropical to subtropical climatic with intermittent dry semiarid climatic conditions across Late Cretaceous-Early Paleocene during Deccan transition.

Keywords: aquatic; palynoflora. Deccan intertrappean: Late Cretaceous-Early Paleocene

Date: August / Agosto 9

Time: 15:40-16:00

Sanchez Botero et al. Cretaceous palynostratigraphy in the Caguán-Putumayo Basin, Colombia: an example of data integration in hydrocarbon exploration.

C.A. Sanchez Botero^a,d, G. Rodríguez^a, L.M. Maya^b, J.M. Sierra^b, A.M. Ramirez^b, and M. Rueda^c

^aCentro de Innovación y Tecnología ICP-ECOPETROL, Piedecuesta, Santander, Colombia; ^bVicepresidencia de Exploración-ECOPETROL, Bogotá, Colombia; ^cPaleoflora LTDA, Zapatoca, Santander, Colombia; ^dTIP-CISLAB, Girón, Santander, Colombia.

The Cretaceous of the Caguán-Putumayo basin in southern Colombia has many prospective levels of interest for oil exploration and production, mostly related with sandstones within a predominant shaly to calcareous sequence. The stratigraphic framework has been mainly correlated using three Maximum Flooding Surfaces (MFS) that have been used to interpret their lateral extent and in the understanding of the possible reservoirs in this basin. These surfaces have been named, from oldest to youngest, as SI-C, SI-B and SI-M. To corroborate their behavior, extent and relative age, the stratigraphic location of these surfaces was integrated with biostratigraphic events found in palynological analyses from 13 drilled core wells. These data were integrated and interpreted using RASC (Ranking and Scaling) statistical analysis; this technique allows to give an optimal order to the observed events. The most important events were selected from each well, especially the Last Appearance Datum (LAD), as well as events with high relative abundances (ACME) of species that have been recorded in previous works as characteristic of a particular zone. Maximum Flooding Surfaces were also included to evaluate their stratigraphic position with respect to biostratigraphic events.

The palynological results indicate that two biozones can be recognized in the Cretaceous sequence, the Cyatheacidites zone (Albian – Turonian) which is subdivided into the Heteroretitrescolpites and Callialasporites subzones, and the Dinogymnium zone (Coniancian - Campanian) which is subdivided into the Dinogyminum ACME and Droseridites-Amorfo subzones. The RASC analysis shows 25 relevant events in the sequence, gathered in three main groups. From base to top, it was observed that the first group is defined in the Cyatheacidites zone, the second in the Droseridites-Amorphic subzone, and the last one with the Dinogymnium ACME subzone.

It was also observed a close relationship between the stratigraphic location of the MFS and some events and zones of the basin. SI B is related to the upper part of the Cyatheacidites zone and SI M to the Dinogymnium ACME event. These results will allow to compare, with constrained stratigraphic resolution, the Cretaceous sequence of Cagúan Putumayo with other basins of Northern South America in order to improve the knowledge of its evolution and extent its interest in oil exploration.

Keywords: Caguán-Putumayo; Cretaceous; Hydrocarbon; Villeta Formation.

Date: August / Agosto 9

Time: 15:20-15:40

Gibson et al. A globally wetter Middle Miocene with a narrower intertropical convergence zone

M.E. Gibson^ab, J.M.K. O’Keefe^c, N.B. Nuñez Otaño^d, I.C. Romero^c, S. Warny^e, I. Nkau^f, C. Todd^g and M.J. Pound^a

^aDepartment of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK; ^bDepartment of Geology and Geography, West Virginia University, Morgantown, WV 26505, USA, ^cDepartment of Physics, Earth Science, and Space Systems Engineering, Morehead State University, Morehead, KY 40351, USA; ^dLaboratorio de Geología de Llanuras. Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante. CONICET (National Scientific and Technical Research Council), Argentina; ^eCenter for Excellence in Palynology, Department of Geology & Geophysics, and Museum of Natural Science, Louisiana State University, Baton Rouge, LA 70803, USA; ^fJesmond Park Academy, Jesmond Park West, Newcastle-upon-Tyne NE7 7DP, UK; ^gSouthmoor Sixth Form, Ryhope Road, Sunderland SR2 7FT, UK.

The Middle Miocene Climatic Optimum (MCO; 16.9-14.7Ma) was the warmest interval of the Neogene and is a potential analogue for the IPCC RCP 4.5-6.0 (intermediate scenarios). Global mean annual temperatures are estimated to have been 4–6°C warmer and pCO₂ was slightly higher than present day (above 500 ppm), with an asymmetric latitudinal temperature gradient, tropical temperatures in the mid-latitudes and reduced polar ice sheets. However, our understanding of Middle Miocene terrestrial climate at broad spatial scales is still developing as there are difficulties reconciling proxy-based climate reconstructions with climate models.

One of the current views of Miocene terrestrial climate is based on the Co-existence Approach which has given a broad view of global temperature and precipitation across the Neogene. However, the Co-existence Approach reconstructs an equal likelihood range for climate parameters that can be wide and therefore hampers our understanding the water cycle. These reconstructed ranges also hinder quantitative data-model comparisons (proxy-ranges vs. climate model uncertainty).

Here we present the first global reconstruction of mean annual precipitation and seasonality from 189 Middle Miocene sites. We use two probability-based terrestrial paleoclimate reconstruction techniques, CREST (Climate Reconstruction SofTware) and CRACLE (Climate Reconstruction Analysis using Coexistence Likelihood Estimation), that employ Bayesian and likelihood estimation probability respectively to generate 2σ confidence intervals.

This is the first application of these models at a global scale. Our results show a globally wetter than present-day world, with the exception of a narrow band around the equator. This we attribute to a narrower Intertropical Convergence Zone that, due to the asymmetric distribution of ice in the Middle Miocene, was also located in the northern hemisphere over a yearly average.

The impacts of climate change on the global hydrological cycle will have profound impacts on society. Changes in precipitation will be a cause of concern for flood defense and accompanied infrastructural and financial challenges, water scarcity and agricultural productivity, ecosystem functioning and biodiversity. This statistically generated terrestrial climate reconstruction for the MCO will aid in the evaluation of climate reconstruction models in deep time, enabling an understanding of hydrology in the globally warmer conditions of the MCO. This new reconstruction will also contextualize botanical and fungal biodiversity during the MCO.

Keywords: Fungi, Paleoproxy, climate models.

Date: August / Agosto 10

Time: 10:00-10:20

Helenes. Response of Recent to Late Cenozoic Subtropical and Tropical Dinoflagellate Assemblages to Climatic/Oceanographic Changes

Javier Helenes^a

^aCentro de Investigación Científica y de Educación Superior de Ensenada, Baja California

There is much information on climatic changes and their reflection by dinoflagellate cyst assemblages (DCA) in high latitude sites, and comparatively less is known from tropical to subtropical localities. To diminish this imbalance, we present Recent data from temperate to tropical environments on the Pacific coast of Mexico to identify the response of the DCA to known climatic events and changes. In particular, they reflect marine primary productivity (MPP) and are influenced by sea surface temperature. We then compare fossil data from similar environments in the Eastern Pacific to interpret oceanographic changes in the Late Cenozoic. Our recent database reflects regional climatic-oceanographic changes on yearly to decadal scales, indicating that MPP is directly related to cyst concentration, and it is modulated by climatic factors, mainly in the tropical area. Additionally, the proliferation of dinoflagellates is usually directly related to heterotrophic taxa, so an H-A Index helps identify high productivity intervals. The current global warming is strongly reflected by increasing MPP, mainly in the tropical locality, while it is almost absent in the cool site. DCA reflects similar patterns of MPP in sequences from offshore Costa Rica and western Colombia in Middle to Late Miocene and an Oligo-Miocene sequence from western Baja California.

Date: August / Agosto 10

Time: 8:30-9:00

Korasidis et al. Reworked pollen reduces apparent floral change during the Paleocene-Eocene Thermal Maximum

Vera A. Korasidis^a.b, Scott L. Wing^a, David M. Nelson^c, Allison A. Baczynski^d

^aDepartment of Paleobiology, National Museum of Natural History, Smithsonian Institution, 10th Street & Constitution Ave., N.W., Washington, DC 20013-7012, USA; ^bSchool of Geography, Earth and Atmospheric Sciences, University of Melbourne, Parkville, VIC 3010, AUS; ^cAppalachian Laboratory, University of Maryland Center for Environmental Science, Frostburg, MD 21532, USA; ^dDepartment of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA

Plant megafossils from the Paleocene-Eocene Thermal Maximum (PETM) in the Bighorn Basin, USA, document a dramatic shift in floral composition whereas palynofloral change from the same sections has appeared to be more subtle. We investigated this discrepancy by quantifying pollen preservation and by measuring the stable carbon isotope composition of specific pollen taxa. Pollen grains belonging to two common latest Paleocene taxa are poorly preserved in PETM samples, and the δ¹³C_pollen values of these taxa are similar during the latest Paleocene and PETM. In contrast, pollen grains of a tropical taxon that became more abundant during the PETM are pristine and their δ¹³C_pollen values are ~4‰ lower during the PETM than latest Paleocene. More broadly, pollen grains belonging to lineages currently centered in temperate climates are typically poorly preserved when found in PETM samples, whereas in the same samples pollen belonging to lineages now centered in the tropics are well preserved. Differences in preservation and isotopic composition indicate extensive redeposition of older pollen grains during the PETM. Increased abundance of Cretaceous palynotaxa in PETM samples confirms erosion and redeposition, likely resulting from more episodic and intense precipitation. Excluding reworked pollen from analyses reveals that, as in the megaflora, temperate taxa were absent during the body of the PETM at the time when dry tropical taxa briefly appeared. Blurring of microfloral change by reworking may be a common feature of major climatic perturbations that destabilize landscapes, leading to underestimation of the rate and magnitude of floral response to past global change.

Keywords: PETM; Bighorn Basin; pollen preservation; reworking; δ¹³C

Date: August / Agosto 9

Time: 16:20-16:40

O’Keefe et al. Apocalypse past: coastal fungal assemblages following warming events

Jennifer M.K. O’Keefe^a, Ingrid C. Romero^a, Maggie Stephenson^a,b, Tyler Spears^a, and Noelia B. Nuñez Otaño^c

^aDepartment of Physics, Earth Sciences, and Space Systems Engineering, Morehead State University, Morehead, KY, USA; ^bCenter for Excellence in Paleontology, East Tennessee State University, Johnson City, TN, USA; ^c Laboratorio de Geología de Llanuras, Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante, CONICET (National Scientific and Technical Research Council), Argentina.

Fungal community response to warming events is of great interest to mycologists and paleoecologists as they seek to develop models to forecast future changes. Equally important, however, is how fungal communities respond to cooling conditions and whether those responses can be teased apart from response to changing depositional environments. Here we examine two different examples of fungal assemblages preserved in coastal sediments following warming events: those from the Carrizo Formation (Ypresian, Eocene, Texas) and those from the Upper Hattiesburg Formation (Serravallian-Tortonian, Miocene, Mississippi). The sand-dominated Carrizo Formation was deposited in a shallow marine setting, possibly a tidal delta, while the clay-dominated Upper Hattiesburg was deposited as a series of interfluvial overbank deposits adjacent to a coastal fluvial system. As such, the fossil fungal communities preserved in each setting are different, however, both record variations in fossil fungal assemblage upward. Preliminary interpretation of these results indicates that those assemblages in the Carrizo Formation record a transition from tropical to sub-tropical wet to sub-tropical less-wet conditions while those in the Hattiesburg Formation record a transition from warm, moist temperate conditions to drier temperate conditions.

Keywords: Fossil Fungi, Hattiesburg Formation, Claiborne Formation

Date: August / Agosto 10

Time: 9:40-10:00

Plata et al. Maastrichtian to Neogene Palynology from the Colombian Caribbean (Sinú-San Jacinto and Cesar Ranchería basins)

Ángelo Plata ^a,b, Andrés Pardo-Trujillo² and José Abel Flores^a

^aUniversity of Salamanca, 340007 Salamanca Spain; ^bInstituto de Investigaciones en Estratigrafía IIES-Universidad de Caldas, Calle 65 # 26-10, Edificio Orlando Sierra, 2 piso, Manizales, Colombia.

The Colombian Caribbean has a sedimentary record ranging from the Late Cretaceous to the Quaternary. Its high number of oil and gas seeps indicates an active petroleum system and, therefore, potential for hydrocarbon exploration. The study of calcareous and organic walled microfossils has been one of the main tools to know the age and depositional environment of the sedimentary deposits. However, very little information has been published. To fill this gap, in recent years the National Hydrocarbon Agency (ANH) has carried out regional geological studies that include seismic line acquisition, drilling of core wells, geological mapping and different types of sample analysis. The University of Caldas is studying the micropaleontology (palynology, foraminifera, nannofossils and ostracods) of drill core samples from a record ranging from the Maastrichtian to the Miocene.

This study presents palynological information from 875 samples obtained from 17 core wells in the Cesar-Ranchería and Sinu-San Jacinto basins. In the wells drilled in the Cesar-Ranchería basin (5 wells), a continuous record from the Maastrichtian to the Eocene (Molino, Barco, Los Cuervos and Tabaco? formations) is observed. The palynomorphs are very well preserved and their Thermal Alteration Index indicates early stage of hydrocarbon generation. The ratio of marine vs. terrestrial palynomorphs suggests a shift from marine to continental environments between the Maastrichtian and Paleocene. The presence of Malvaceae (Bombacacidites annae among others), the high content of Araceae (Proxapertites operculatus), Arecaceae (Mauritiidites franciscoi, Longapertites vaneendenburgui) and fungal remains (e.g. Diporopollis assamica), suggest lowland tropical rainforest. The sedimentary record of the Sinú-San Jacinto Basin (12 wells) includes Maastrichtian rocks (Cansona Fm.) with well-preserved marine and terrestrial palynomorphs. Over them, there are discordant Eocene deposits (San Cayetano Fm.). The palynomorphs are well preserved and reach hydrocarbon generation window. During the early-middle Eocene, a diverse association of Malvaceae (Bombacacidites) and Arecacea (e.g. Psilamonocolpites, Clavamonocolpites, Gemmamonocolpites, Spinizonocolpites) is observed, as well as variations in the percentage of marine vs. terrestrial palynomorphs, indicating changes in relative sea level. During the Oligocene-Lower Miocene deposits (Ciénaga de Oro Formation), marine palynomorphs and mangrove vegetation suggest littoral environments with fluctuations in the coastline. In general, the palynological zonation proposed for the Cenozoic of the Llanos basin can be applied to the Caribbean with slight variations. New pollen and spore species are recognized that seem to have biostratigraphic value.

Key Words: Palynology, Maastrichtian, Paleogene, Neogene, Colombian Caribbean.

Plata et al. Palinología del Maastrichiano al Neógeno en el Caribe Colombiano (cuencas Sinú-San Jacinto y Cesar Ranchería).

Ángelo Plata ^a,b, Andrés Pardo-Trujillo² and José Abel Flores^a

^aUniversity of Salamanca, 340007 Salamanca Spain; ^bInstituto de Investigaciones en Estratigrafía IIES-Universidad de Caldas, Calle 65 # 26-10, Edificio Orlando Sierra, 2 piso, Manizales, Colombia.

El Caribe colombiano presenta un registro sedimentario que va desde el Cretácico Superior al Cuaternario. Su elevado número de rezumaderos de petróleo y gas indica un sistema petrolífero activo y, por tanto, potencial para la exploración de hidrocarburos. El estudio de microfósiles calcáreos y de pared orgánica han sido una de las principales herramientas para conocer la edad y el ambiente de depósito de los depósitos sedimentarios. Sin embargo, muy poca información ha sido publicada. Para llenar este vacío la Agencia Nacional de Hidrocarburos (ANH) ha realizado en los últimos años estudios geológicos regionales que incluyen adquisición de líneas sísmicas, perforación de pozos corazonados, cartografía geológica y diferentes tipos de análisis de muestras. La Universidad de Caldas se encuentra estudiado la micropaleontología (palinología, foraminíferos, nanofósiles y ostrácodos) de muestras de núcleos de perforación de un registro que va desde el Maastrichtiano hasta el Mioceno.

En este estudio se presenta la información palinológica de 875 muestras obtenidas en 17 pozos corazonados en las cuencas Cesar-Ranchería y Sinú-San Jacinto. En los Pozos perforados en la cuenca Cesar-Ranchería (5 Pozos), se observa un registro continuo desde el Maastrichtiano hasta el Eoceno (formaciones Molino, Barco, Los Cuervos y Tabaco?). Los palinomorfos se encuentran muy bien preservados y, su Índice de Alteración Térmica indica que las rocas se encuentran en la fase temprana de generación de hidrocarburos. La relación de palinomorfos marinos vs. terrestres sugiere, un cambio de los ambientes marinos a continentales entre el Maastrichtiano y el Paleoceno. La presencia de Malvaceae (Bombacacidites annae entre otras), el alto contenido de Araceae (Proxapertites operculatus), Arecaceae (Mauritiidites franciscoi, Longapertites vaneendenburgui) y restos de hongos (e.g. Diporopollis assamica), sugieren ambientes de bosques tropicales húmedos de tierras bajas. El registro sedimentario de la Cuenca Sinú-San Jacinto (12 pozos), incluye rocas del Maastrichtiano (Fm. Cansona) con palinomorfos marinos y terrestres bien preservados. Sobre ellas, se encuentran discordantemente depósitos del Eoceno (Fm. San Cayetano). Los palinomorfos presentan una buena preservación y se encuentran en la ventana de generación de hidrocarburos. Durante el Eoceno temprano-medio, se observa una diversa asociación de Malvaceae (Bombacacidites) y Arecacea (e.g. Psilamonocolpites, Clavamonocolpites, Gemmamonocolpites, Spinizonocolpites), así como variaciones en el porcentaje de palinomorfos marinos vs. terrestres que indican cambios en el nivel relativo del mar. En los depósitos del Oligoceno-Mioceno inferior (Formación Ciénaga de Oro) se observan palinomorfos marinos y de vegetación de manglar que sugieren ambientes litorales con fluctuaciones en la línea de costa. En general, la zonación palinológica propuesta para el Cenozoico de los Llanos Orientales y el Piedemonte puede ser aplicada en el Caribe con ligeras variaciones. Se reconocen nuevas especies de polen y esporas que, al parecer, tienen valor bioestratigráfico.

Palabras Clave: Palinología, Maastrichtiano, Paleógeno, Neógeno, Caribe Colombiano

Keywords: Caguán-Putumayo; Cretaceous; Hydrocarbon; Villeta Formation.

Date: August / Agosto 10

Time: 9:20-9:40

Taiwo et al. Lake chemistry variation in the Lockichar and Kerio Valley Basins, Kenya

O.M. Taiwo ^a and D.W. Jolley^a

^a School of Geosciences, University of Aberdeen, Scotland, United Kingdom. AB24 3UE

This study compares the water chemistry of two lakes within the Kenyan rift system; the northern Lokichar Basin and the southern Kerio Valley Basin. Loperot-1 well in the Lockichar Basin is made up primarily of Paleogene to middle Miocene sandstones overlying the Precambrian basement. Within the sandstone unit are two prominent shale members; the Palogene Loperot Shale member and the Oligocene Lokhone Shale Member within which ditch cutting samples were processed for palynological studies. Palynonomorph assemblage was good and forms were well preserved, with Pediastrum, palm pollen and fern spores dominating the total organic assemblage. The lithology of the Kerio Valley Basin from Cheptuket-1 well is comprised of the basal phonolites, claystones, greenish evaporite-rich claystones and capped by the Ewalel Phonolites and Quaternary sands. The evaporites were mainly gypsum and halites indicative of low lake water level and high salinity. Ditch cutting samples within the sedimentary Tambach and Ngorora formations of the Cheptuket-1 well yielded low palynomorph diversity with Botryococcus braunii dominating the total organic assemblage. Though both basins, Lockichar and Kerio Valley Basin were dominated by freshwater chlorophycean algae, Pediastrum sp and Botryococcus braunii, the total absence of Pediastrum sp. within Cheptuket-1 well with corresponding Botryococcus braunii bloom within it shows a major variation in lake chemistry to the Lockichar Basin which has high recovery of Pediastrum sp. and no Botryococcus braunii count in Loperot-1 well. The variation in lake water chemistry within both basins might have resulted from acidification and alkalinity of the lakes which might be closely linked to the lake recharge system.

Keywords: Lake Chemistry, acidification, alkaline lake.

Date: August / Agosto 10

Time: 8:10-8:30

Torricelli et al. Paleoclimatic and depositional controls on the palynostratigraphy of the Malembo Formation (Oligocene-lower Miocene, offshore Angola)

S. Torricelli, G. Knezaureka^a and E. Menichettia^a

^a Eni S.p.A. Natural Resources, Upstream & Technical Services, 20097 San Donato Milanese, Italy

In 2006 Eni Exploration & Production took over the operatorship for hydrocarbon exploration in Block 15/06 offshore NW Angola. Since then, more than thirty exploration wells have been drilled targeting the Oligocene-Miocene deepwater turbidite channel systems of the Lower Congo Basin ascribed to the Malembo Formation.

Biostratigraphic studies carried out in-house yielded crucial information to pinpoint correlations of the main horizons in 3D seismic projects. The identification of a series of organic-walled dinoflagellate cyst events (highest and lowest occurrences, influxes and acmes), recurring in the same stratigraphic position in different wells and cross-calibrated by calcareous nannofossil data, resulted in a zonation suitable for age control and correlation of Oligocene and lower Miocene sequences on a regional scale.

Proceeding downwards in the stratigraphy of the examined succession, the lowest occurrence of Pyxidinopsis pastilliformis, detected within the CN3 nannofossil Zone, approximates the Langhian-Burdigalian boundary, whereas the lowest occurrences of Sumatradinuim druggii and Sumatradinium hispidum occur at the base of the CN2 nannofossil Zone in the Burdigalian. The lowest occurrences of Sumatradinium soucouyantiae and Barssidinium taxandrianum fall at the Burdigalian-Aquitanian transition within the Zone of acme of Hystrichokolpoma rigaudiae that seems to reflect a

relative climate warming interlude following the Mi-1a cooling pulse that is instead recorded by the underlying acmes of cold water taxa Cribroperidinium tenuitabulatum and Systematophora- Cleistosphaeridium spp. The presence of Chiropteridium spp. and Membranophoridium aspinatum is limited to the upper part of the Chattian, hence in the Angolan basin these taxa have a limited stratigraphic distribution compared to the North Atlantic and Mediterranean records. An influx of Tuberculodinium vancampoae, possibly related to a warmer interlude during a period of overall climate cooling, occurs in proximity of the Chattian-Rupelian boundary. The nearly synchronous highest occurrences of Gerdiocysta conopeum, Eocladopyxis peniculata and Heterosphaeridium sp. provide a robust infra-Rupelian biohorizon. Further down in the Rupelian, the influxes of Pentadinium laticinctutm and Distatodinium paradoxum are interpreted as responses to Oi-2 cooling pulse. The lowest occurrence of G. conopeum, detected in the basal part of the NP23 nannofossil Zone, corresponds to the global first appearance of this excellent Rupelian marker.

The recorded alternation of influxes and acmes of Gonyaluacoid dinocyst taxa indicative of cooler and warmer water conditions was apparently climate-driven, paced by cooling pulses and relatively warmer interludes characterizing the overall climate cooling trend during the Oligocene and early Miocene. The lack of acmes of Protoperidinioid cysts suggests that climate, rather than constantly elevated nutrient levels ensured by the Congo River discharge, was the discriminant factor triggering blooms of these Gonyaluacoid cyst-forming taxa.

In addition to paleoecological factors, hydraulic fractionation resulting from sedimentary processes that transported palynomorphs down the slope as part of turbidite fluxes, contributed to shape the palynological assemblages observed in this study. We suppose that even the taxonomic composition of dinocyst assemblages might have been biased accordingly. At this regard, acmes of Cribroperidinium and Systematophora-Cleistosphaeridium are apparently coeval expressions of Mi-1a cooling pulse, but they never occur in the same samples. The partition of proximate (Cribroperidinium) and chorate cysts (Systematophora-Cleistosphaeridium) was probably due to hydraulic sorting operated by currents that displaced these taxa offshore from the coastal settings where they lived.

Terrestrial palynomorphs are abundant in the examined material but useless for industrial biostratigraphy in the Lower Congo Basin, hence they were not considered for the present zonation. Indeed, all sporomorphs of the Malembo Formation underwent aerial and aquatic dispersion, fluvial transport and hydraulic sorting operated by turbidity currents before final sedimentation into deep marine environments, far from the settings where they originated. Therefore, quantitative patterns of their stratigraphic distributions do not automatically reflect changes in the hinterland vegetation but changes in sedimentological processes that artificially enhanced or diminished their abundances. In our experience, the marked quantitative fluctuations of terrestrial palynomorphs in deepwater turbidites do not have the potential to be synchronous except on short distances and depending on alignment of samples with sediment flux directions.

The delivery of large volumes of sands into deepwater settings via gravity-driven fluxes was favored by sea-level drops associated with pulses of climate cooling and Antarctic ice-sheet growth.The combination of paleoclimatic and depositional factors finally shaped the composition of the palynological assemblages under investigation.

Keywords: biostratigraphy, dinoflagellate cysts, sporomorphs, paleoclimate, Oligocene, Miocene

Date: August / Agosto 10

Time: 9:00-9:20

Avendaño. Possible association of particle size and planetary obliquity during the Late Holocene in the Lachuá Region, Guatemala

C.E. Avendaño^a,b,c

^aGrupo de Ciencias de la Tierra y Soberanía Local; ^bProyecto Arqueológico Salinas Nueve Cerros, Guatemala, Guatemala; ^cEscuela de Biología, Universidad de San Carlos de Guatemala, Guatemala, Guatemala

The climatology of our planet responds to multiple factors linked to multiple spatiotemporal scales. Among these factors, we can find the astronomical ones described by the Milankovitch Cycles, which operate at the millennial-scale, and other ones such as the zonal-related atmospheric latitudinal cells. Due to these various factors, climatic processes cannot be explained under linear models due to distortion of the azonal process, such as topographic barriers and elevational and continentality gradients.

Guatemala is currently localized at the northern displacement limit of the Intertropical Convergence Zone (ITCZ). This thermo-pluvial non-geographic equator varies in latitudinal maximum and minimum migration spans thousands of years. Despite Guatemala’s narrow territory, its climatic variability is amplified due to the multiple factors mentioned above.

Based upon a sedimentary core from the Lachua lakeshore at the Lachua Lake National Park, along the Northern Transversal Strip, the paleoenvironment of the last six millennia was reconstructed after combining multiple paleoecological proxies (e.g., particle size, Zygnemataceae spores, pollen and fungal spores). The particle size (PS) of the last millennia has decreased progressively from sand to silt-clay sizes, suggesting a stratigraphic sequence associated with obliquity and a more extensive influence of the North American Monsoon (NAM).

The Lachua PS database positively correlated with the Cariaco Basin titanium sedimentary record. This pattern suggests that parallel to the decreasing precipitation in northern South America during the Late Holocene due to the southern ITCZ migration, precipitation in the Lachua Region has been increasing, possibly to a more extensive influence of the NAM.

Correlation analysis, including global databases, can enrich localized observations by providing a regional context that facilitates visualizing non-linear processes. The results presented suggest the need for further exploration regarding paleoenvironmental reconstructions to strengthen climate change predictions, even more in narrow territories that exhibit complexity, such as Guatemala.

Keywords: Paleoecology, Milankovitch Cycles, transgression, sedimentary core, Mesoamerica.

Avendaño. Posible asociación del tamaño de partícula con la Oblicuidad planetaria durante el Holoceno tardío en la Región de Lachuá, Guatemala

C.E. Avendaño^a,b,c

^aGrupo de Ciencias de la Tierra y Soberanía Local; ^bProyecto Arqueológico Salinas Nueve Cerros, Guatemala, Guatemala; ^cEscuela de Biología, Universidad de San Carlos de Guatemala, Guatemala, Guatemala

La climatología planetaria responde a múltiples factores que se vinculan a través de múltiples escalas en el espacio y en el tiempo. Entre estos factores, se encuentran los astronómicos descritos principalmente por los Ciclos de Milankovitch que se manifiestan en la escala milenaria, además de otros como la zonalidad de celdas atmosféricas ajustadas a la latitud geográfica. Es por esta razón que los procesos climatológicos no pueden explicarse bajos modelos lineales, ya que procesos azonales los distorsionan, lo cual presenta un reto cuando se integran factores como barreras topográficas, gradientes altitudinales y continentales.

El territorio de Guatemala se localiza cercano al límite máximo norte de la Zona de Convergencia Intertropical (ZCIT), la cual, al representar el ecuador térmico-pluvial, varia en la escala milenaria en sus distancias máxima y mínima al ecuador geográfico. Entonces, a pesar del estrecho territorio guatemalteco, su variabilidad climatológica es amplia por la interacción de los múltiples factores ya mencionados.

A partir del estudio de un núcleo sedimentario de las orillas de la Laguna de Lachuá, localizada en el Parque Nacional Laguna Lachuá situado en la Franja Transversal del Norte, se logró la reconstrucción del paleoambiente de los últimos ca. 6000 años, luego de combinar múltiples indicadores paleoecológicos (e.g., tamaño de partícula, esporas de Zygnemataceae, polen y esporas fúngicas). La tendencia del tamaño de partícula (TP) de los últimos milenios ha sido progresivamente de arenas hacia limo-arcillas, en un proceso alternante que sugiere ciclos de una secuencia estratigráfica, posiblemente asociada parcialmente a la oblicuidad planetaria y a una mayor influencia del Monzón Norteamericano (MNA).

La comparación de la base de datos de TP de Lachuá con valores de titanio de la Bahía de Cariaco, presentó una correlación positiva. Este patrón sugiere que a medida que durante la segunda mitad del Holoceno el norte de Suramérica tiende a una menor precipitación, por la migración sureña de la ZCIT, la región de Lachuá tiende a una mayor precipitación, posiblemente por la mayor influencia del MNA.

Las correlaciones de bases de datos globales pueden enriquecer resultados puntuales ya que proveen de un contexto regional que puede facilitar la visualización de procesos no lineales. Los resultados presentados sugieren una exploración más profunda en cuanto a las reconstrucciones paleoambientales para fortalecer las predicciones de cambio climático futuro, en territorios estrechos pero complejos como el de Guatemala.

Palabras clave: Paleoecología, Ciclos de Milankovitch, transgresión, núcleo sedimentario, Mesoamérica.

Date: August / Agosto 10

Time: 14:20-14:40

Francois et al. Paleoenvironmental history of South Central Chile. The sedimentary and palynological record of "Laguna Verde wetland" (36°47'S), Hualpén Peninsula, Bío-Bío District, Chile

J.P.Francois^a, Y.Aguirre^a, P. Hernández^a, Cerdaa & I. Schneider^b

^aLaboratorio de Geografía Ambiental y Palinología (Lab GAP-UPLA), Departamento de Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile; ^bLaboratorio de Dendrocronología y Estudios Ambientales, Instituto de Geografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.

A new sedimentological and palynological record from the Hualpén Peninsula, BioBio district, reconstructs the elusive environmental history during the middle to late Holocene transition in Southern Central Chile (34°-38°S). The study area is located into the "Parque Rio Zañartu”, a Wild Life Area were a small wetland surrounding by native vegetation occurs (i.e. sclerophyllous forest). In this location, a number of activities were executed in order to: (i) characterize the modern vegetation and pollen rain that would later allow interpreting the pollen record, and (ii) the recovery of multiple sediment cores from the wetland with the purpose to reconstruct the environmental history. In specific, a detailed survey to characterize the predominant plant communities into the wetland catchment (170 ha) was performed, and later plant communities covers were estimated by means of remote sensing and GIS analyses. For each of these plant communities, soil samples were obtained to characterize modern pollen rain. Also, multiple sediment cores (n=5) were extracted from different sectors of the Laguna Verde wetland (36º47'S, 73º09'W; 22 m.a.s.l; ~4 ha), in order to examine the evolution of different sedimentary environments occurring on. Later, soil samples and sedimentary cores were geochemically (e.g. LOI) and palynological analyzed in the laboratory with standard techniques. Additionally, several radiocarbon dates (n=15) provides a robust chronology for the sedimentary and pollen record, allowing to examine the environmental history during the Holocene in the study area and make comparisons with other records of Central Chile. The results indicate the feasibility to recognize main plant communities by its pollen rain, with some distinctive taxa as key. On the other hand, the sedimentary and pollen record show a remarkable transition during the middle Holocene, suggesting an underlying climatic mechanism. In particular, the sedimentary record of Laguna Verde wetland indicates that site formation occurs around 6,800 cal years BP, as result of a damming process by dunes in the wetland micro-basin. The palynological record shows a predominance of non-arboreal taxa during this first phase, with an increase in the arboreal taxa around 5000 cal years BP. This change is encompassing by an important increase in the input of lithic materials mobilized by wind and precipitation, and the formation of a permanent body of water (e.g.lagoon). Finally, an abrupt change in the sedimentological and the palynological record is observed around 1850AD, related with a transformation in the vegetal landscape and the sedimentary regime. Specifically, a decrease in native tree taxa and the appearance of exotic taxa account for human activity in the wetland micro-basin, while a significant increase in detrital sedimentary input is observed. This change demarks the transformation from a lagoon to the current wetland, and reveals the relationships between human activity and surface processes such as erosion and runoff. In summary, this study highlight the potential to identify paleoenvironmental changes associated with natural (e.g. climate) and anthropogenic processes by means of sedimentological and palynological records from wetlands in Central Chile. Furthermore, the results provide of new and relevant information for the mid Holocene transition for Southern Central Chile, indicating an important shift in the Southern Westerlies Wind belt dynamics.

Keywords: Central Chile; Bío-Bío District; sclerophyllous forest; pollen rain; remote sensing; Mid Holocene transition, Southern Westerlies

Francois et al. Tras la historia paleoambiental de Chile Central Sur. El registro sedimentario y palinológico del humedal “Laguna Verde (36°47´S)”, Península de Hualpén, región del Bío-Bío, Chile

J.P.Francois^a, Y.Aguirre^a, P. Hernández^a, Cerda^a & I. Schneider^b

^aLaboratorio de Geografía Ambiental y Palinología (Lab GAP-UPLA), Departamento de Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile; ^bLaboratorio de Dendrocronología y Estudios Ambientales, Instituto de Geografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.

La presente presentación de cuenta de los resultados de un trabajo inédito que incluye el primer registro palinológico para el Holoceno medio y tardío en la porción sur de Chile Central. El área de estudio se encuentra ubicada en el Santuario de la Naturaleza “Parque Rio Zañartu”, localizado en la Península de Hualpén, región del Bío-Bío, Chile. En dicha locación, se realizó un trabajo integral que busco en primera instancia caracterizar la vegetación a fin de obtener muestras actuales de la lluvia polínica que permitieran posteriormente interpretar el registro polínico. Para esto, primeramente se realizó un trabajo en terreno que permito identificar las comunidades vegetales predominantes en el área, y que fue apoyado por un levantamiento de las coberturas vegetales utilizando teledetección. Posteriormente, múltiples testigos de sedimentos (n=5) fueron extraídos desde diferentes sectores del humedal Laguna Verde (36º47’S, 73º09’O; 22 m.s.n.m), ubicado en la porción sur de la Península de Hualpén y cuya superficie es de ~4 ha. Los testigos sedimentarios fueron analizados mediante técnicas estándares como la pérdida por ignición que permitieron realizar correlaciones estratigráficas entre los diferentes ambientes sedimentarios. Así también, dataciones radiocarbonicas (n=15) fueron obtenidas de los diferentes núcleos de sedimentos lo cual en conjunto con el análisis palinológico permitió examinar la historia paleoambiental del área de estudio y a su vez realizar comparaciones de una manera adecuada con otros registros que igualmente pretenden descifrar la historia climática de Chile central durante el Holoceno. Los resultados dan cuenta de la notable transición climática que ocurre en Chile Central durante el Holoceno medio, y el cual está aún lejos de ser comprendido en su real magnitud. En este caso, el registro sedimentario del Humedal de Laguna Verde pareciera dar cuenta que la señal climática se ve expresada en el registro sedimentario de manera sitio dependiente, en relación a factores como la geomorfología local. En específico, el registro sedimentario da cuenta de la formación de un cuerpo de agua en torno a los 6800 años cal AP, producto del represamiento por una duna. El registro palinológico, muestra una predominancia de taxa no arbóreos durante esta primera fase, siendo posteriormente observable un aumento de estos en torno a 5000 años cal AP. Así también, se observa en este punto un cambio importante en el aporte de materiales líticos movilizados por viento y precipitación dando cuenta de la formación de una cuerpo de agua permanente (.e. laguna). Finalmente, un abrupto cambio tanto en los sedimentos como en el registro palinológico se observa en torno a 1850AD, dando cuenta

de una transformación en el paisaje vegetal y en el régimen sedimentario. En específico, una disminución en los taxa arbóreos nativos y la aparición de taxa exóticos da cuenta de la actividad humana en la cuenca, a su vez que se observa una aumento importante en el aporte sedimentario detrítico. Este cambio marca la transición desde una laguna al actual humedal, y deja en evidencia las relaciones entre la actividad humana y los procesos de superficie como lo son la erosión y escorrentía. En resumen, los resultados reflejan el potencial de identificar en los registros palinológicos y sedimentológicos provenientes de humedales de Chile Central cambios paleoambientales asociados a procesos naturales (e.g. clima) y antropogénicos, dando a su vez cuenta de la naturaleza retrodictiva de los métodos y aproximaciones utilizados en estudios de esta naturaleza.

Palabras clave: Chile Central; Bío-Bío; lluvia de polen; teledetección; transición Holoceno medio.

Date: August / Agosto 10

Time: 13:40-14:00

Hooghiemstra. Colombia’s amazing Quaternary History: Climate, Flora, Páramos and Man

Henry Hooghiemstra & co-workers

Department of Ecosystem and Landscape Dynamics, University of Amsterdam, Amsterdam, The Netherlands. E-mail: H.Hooghiemstra@uva.nl

Anticipating on the Earth’ future requires a thorough understanding of the past. High tropical mountains act as a laboratory-setting where past and ongoing ‘experiments’ with climate-driven environmental change can be studied. In this talk we explore the development of the Andean flora and we show the long pollen records of climate change from the deep sedimentary basins of Bogotá and Fúquene. The anatomy a glacial-interglacial cycles hints to drivers and operating mechanisms and sets the scene how climate-driven environmental conditions and biodiversity in high mountains has changed in the past. In a 10-minutes video Sky Islands we present the flickering connectivity system (FCS), a proposed mechanism to explain the stunning high biodiversity in the páramos of the Northern Andes. Altitudinal shifts of vegetation belts in the young profiled northern Andes, at millennial to orbital time scales (41 and 100 kyr), cause multiple events of isolation and connection of gene pools. Each mountain range has a characteristic profile with a cordillera-specific history as a consequence. For example, the FCS explains why the páramo of the Western Cordillera is less biodiverse as the páramo of the Eastern Cordillera. This video presentation also gives hints for potential changes in the distribution of páramo during the next centuries.

Pollen records are museums of changes in plant assemblages in deep-ecological time. With 60-yr between samples in the 284,000-yr long Fúquene record the composition of mountain forest is monitored some 3 times within the life cycle of its constituents. Resolution is reaching ecologist’s detail of permanent-plot data potentially opening a new field of relevant research questions to be addressed. As is the case with climate conditions, current taxonomic forest composition is of relatively short duration also. Realizing that non-analog plant associations and non-analog climates dominated in the past, hypothesis development should better include this aspect. Although present phytosociological relationships reflect an ephemeral aspect of vegetation, such studies are helpful to infer taxon’s used niche space. Pollen records potentially allow to infer the unused niche space also. An understanding of plant’s genetically constrained niche space, consisting of a used (today) and an unused (e.g. under glacial conditions) niche space, allow plants to respond to climate change by niche tracking. Genetic plasticity is within the total niche space. In relation to current climate change paleoecologists refrain from using the term ‘adaptation’ as the niche space of a plant is a very conservative character in deep-ecological/geological time. Documenting and understanding past and future changes in distribution areas, and fragmentation and connection of gene pools, is helpful in developing current conservation strategies and anticipating the future. The relevance of a good understanding of past ecological conditions is demonstrated with Kyoto Protocol-driven measurements. Recent carbon sequestration in the páramos of Ecuador, Colombia and Venezuela with Mexican pine destroyed much of this precious ecosystem while measurements were politically advertised as adequate and sustainable. Understanding of mountain dynamics during the Quaternary should be better used in the societal and political arena.

Key references

Hooghiemstra H, Sarmiento-Pérez G. Torres Torres V, Berrio J-C, Lourens, L., Flantua SGA 2022. 60 years of scientific deep drilling in Colombia; the north Andean guide to the Quaternary. Sci Drilling 30, 1-15.

Pérez-Escobar OA, Zizka,A, Bermudez MA, Hoorn C, Hooghiemstra H, Pennington RT, Antonelli A, Chomicki G 2021. The Andes through time and the evolution and distribution of Andean floras. Trends Plant Science 26, 1-15.

Mottl O, Flantu SGA, Bhatta KP, Felde VA, Giesecke T, Grimm EC. Haberle S, Hooghiemstra H, Ivory S, Kunes P, Williams JW 2021. Global acceleration in rates of vegetation change over the past 18,000 years. Science 372, 860-864.

Nogué S, Santos AMC, Birks, HJB, Björck S, Castilla-Beltrán A, Connor S, De Boer EJ, Hooghiemstra H, et al. 2021. The human dimension of biodiversity changes on islands. Science 372, 488-491.

Flantua SGA, O’Dea A, Onstein R, Giraldo C, Hooghiemstra, H 2019. The flickering connectivity system of the north Andean páramos. J. Biogeogr. doi: 10.1111/jbi.13607.

Hooghiemstra H, Flantua SGA 2019. Colombia in Quaternary: an overview of environmental and climatic change. In: Gómez-Tapias J (editor), The Geology of Colombia Book, Vol. 4 Quaternary, pp. 33-84. Servicio Geológico Colombiano.

Torres V, Hooghiemstra H, Lourens LJ, Tzedakis PC 2013. Astronomical tuning of long pollen records reveals the dynamic history of montane biomes and lake levels in the tropical high Andes during the Quaternary. Quat Sci Rev 63, 59-72.

González-Carranza Z, Hooghiemstra H, Vélez MI 2012. Major altitudinal shifts in Andean vegetation on the Amazonian flank show temporary loss of biota in the Holocene. The Holocene 22, 1227-1241.

Groot MHM, Bogotá RG, Lourens LJ, Hooghiemstra H et al. 2011. Ultra-high resolution pollen record from the northern Andes reveals rapid shifts in montane climates within the last two glacial cycles. Clim Past 7, 299-316.

Bogotá-A RG, Groot, MHM, Hooghiemstra H et al. 2011. Rapid climate change from north Andean Lake Fúquene pollen records driven by obliquity: implications for a basin-wide biostratigraphic zonation. Quat Sci Rev 30, 3321-3337.

Moscol-Olivera MC, Hooghiemstra H 2010. Three millennia upper forest line changes in northern Ecuador: pollen records and altitudinal vegetation distributions. Rev Palaeobot Palynol 163, 113-126.

Bakker J, Moscol-Olivera M, Hooghiemstra H 2008. Holocene environmental change at the upper forest line in northern Ecuador. The Holocene 18, 877-893.

Date: August / Agosto 10

Time: 10:40-11:10

Mongol and Oboh-Ikuenobe. Comparative analysis of anthropogenic versus climatic influences on the Late Holocene vegetation dynamics in the Northern Neotropics: a palynological approach from Lake Izabal, eastern Guatemala

Erdoo Mongol^a and Francisca E. Oboh-Ikuenobe^a

^aDepartment of Geosciences and Geological and Petroleum Engineering Missouri University of Science and Technology, Rolla MO, USA.

The deterioration of forest communities around the world threatens the sustainable supply of ecosystem services that plants afford to humans and nature. These processes are associated with anthropogenic and climatic forcing at different time scales. The main goal of this study is to understand how tropical vegetation responded to these two sources of variability. Here, we present palynological data from Lake Izabal, eastern Guatemala, spanning the last 1,300 cal yr BP based on extrapolation of five ¹⁴C dates of woody debris in the sediments. Analysis of the relative abundances of pollen reveal distinct alternations between herbaceous and forest associated vegetation groups. These alternations have been evaluated at spatiotemporal scales spanning major anthropogenic and climatic events such as the apogee and demise of the Maya Civilization, the Medieval Climate Anomaly, Little Ice Age, and the Great Dying. The Lake Izabal vegetation responses have been compared with other proxy records within the northern Neotropics to ascertain the regional factors that drive the variability in vegetation patterns. Inferences from this work potentially provide scientific and societal clues for assessing how and why species are preferentially distributed in their current localities.

Keywords: Pollen, herbaceous taxa, forest taxa, MCA, LIA, Maya Civilization

Date: August / Agosto 10

Time: 14:00-14:20

Rodriguez et al. Early Pleistocene Atlantic Forest dynamics in southeastern Brazil.

P.A. Rodríguez-Zorro^a M.P. Ledru^b and C. Favier^b

TROPICOL team members

^aEscuela de Biociencias, Universidad Nacional de Colombia-sede Medellín, Medellín, Colombia; ^bISEM, University of Montpellier, Montpellier, France

Located in the eastern part of Brazil, the Atlantic Forest is one of the most diverse forests in the world, containing high levels of endemism along a latitudinal gradient from 3°S to 30°S. In addition, the influence of the Atlantic Ocean, polar air masses, and monsoon circulation make the area a unique place for regional and global paleoclimatic research. Here we present a new record, the COL17c, located in the Colônia basin in São Paulo, Brazil (23°S, ca. 700 m a.s.l). The record has 115 m of overlapping sediment cores, spanning the first 50 m depth from the basin. We have analyzed the deepest 6 m of COL17c to reconstruct climatic and vegetation changes of the southern tropics during the 40-kyr glacial-interglacial cycles dated between 1.5 and 1.3 Myr. COL17c was analyzed using a multi-proxy approach that included pollen, diatoms, biomarkers, charcoal, and X-Ray fluorescence scanning.

We found that meridional temperature differences regulated the input of moisture at the latitude of Colônia, differentiating glacial and interglacial forest types. The Atlantic Forest was composed of evergreen forest taxa (i.e., Ilex, Myrsine, Myrtaceae, Podocarpus) during interglacials. Conversely, the expansion of grasses, herbs, and semideciduous forest taxa (i.e., Alchornea, Celtis, Bignoniaceae) characterized the glacial periods. During glacial and interglacial periods Araucaria Forest was continuous and expanded at 1.4 Myr, concomitant with an early Pleistocene cooling. Regional fires were observed with low frequencies and did not play a role in shaping vegetation dynamics in our record.

Keywords: Araucaria; 41 kyr world; subtropical front; Southern Hemisphere

Date: August / Agosto 10

Time: 11:10-11:30

Tadoumant et al. Climate history of southwest Morocco: Impacts on vegetation

S. Tadoumant, I. Bouimetarhana, b, Y. Ait Brahimc, R. Cheddadid, M. Hssaisoune a,b and L. Bouchaoua

Laboratory of Applied Geology and Geo-Environment, Ibn Zohr University, Agadir 80035, Morocco; Faculty of Applied Sciences, Ibn Zohr University, Ait Melloul 86153, Morocco; International Water Research Institute (IWRI), Mohammed VI Polytechnic University (UM6P), Ben Guerir 43150, Morocco; University of Montpellier II, CNRS-UM2-IRD, ISEM, France

Terrestrial signals in marine sediment archives are frequently used for paleoclimate reconstructions to understand past human–climate–environment interactions. Southern Morocco is presently subject to severe droughts, desertification, and land degradation, and is likely to face increased climate variability and socio-economic stress in the future. In this study, we used palynological data from two high-resolution marine sediment cores collected off Agadir in southwest Morocco. The modern pollen data was then utilized to interpret the high-resolution pollen record, in combination with published XRF element ratios, deuterium and carbon isotope data (δD and δ13C) from plant waxes in a marine sediment core, and high-resolution stable isotopes (δ18O and δ13C) from speleothem records. The main objective is to evaluate the impact of past climate changes on the vegetation, and to reconstruct the vegetation history during the last 2000 years in the region. The results show that the rapid increase of population in southern Morocco caused land and vegetation degradation due to the expansion of pastoralism and agriculture, especially at the beginning of the Arab invasion of North Africa.

Furthermore, the reconstructed pollen-based vegetation in our marine record suggests an interplay of climate and anthropogenic effects on the landscape. Furthermore, we observed that deciduous oaks occured in more humid forests of the Mediterranean vegetation zone, whereas a decline in deciduous oak pollen percentage indicates drier conditions. The increase of herbaceous taxa might suggest an increase in human impact on the landscape leading to a sparse vegetation cover and subsequently increased erosion.

Keywords: Pollen, climate change, Human impact, Vegetation change, Southern Morocco.

Date: August / Agosto 10

Time: 11:30-11:50

Smith et al. Holocene palynological records of hydroclimate variability in the southeastern United States

Vann Smith^a,b*, Sophie Warny^a,b, Sumar Hart^c, Raheem Taylor^c, Aubrey Hillman^c

^aDepartment of Geology and Geophysics, Louisiana State University, Baton Rouge, LA, USA; ^bMuseum of Natural Science, Louisiana State University, Baton Rouge, LA, USA; ^cDepartment of Atmospheric and Environmental Sciences, University at Albany, State University of New York, Albany, NY, USA.

Recent flooding and drought events in the southeastern United States (US) have caused billions of dollars in economic losses, and anthropogenic global warming is anticipated to cause significant alterations to the regional hydroclimate. The drivers of hydroclimatic variability in the southeastern US are poorly understood, in large part because there are few regional high-resolution records of Holocene paleoclimate. This research project examines a suite of proxies from lake sediment cores in northern and southern Alabama and Georgia in order to identify the timing, magnitude, and spatial variability of precipitation patterns in the Holocene. The goal of the project is to define whether these patterns are predominantly driven by the Pacific North American (PNA) pattern, the North Atlantic Oscillation (NAO), the El Niño-Southern Oscillation (ENSO), or some combination thereof? Modern correlations between mean annual precipitation and these climate oscillations indicate that different spatial patterns of precipitation can be used to identify which of these climate oscillations were predominantly responsible for changing precipitation in the earlier Holocene. Particular focus will be given to sediments deposited 4000 years before present, 2000 years, and during the “Medieval warm period” and “Little ice age”.

Cored sediments from four lakes (Buck Pond, Hanna Pond, Halls Pond, Pigeon Marsh) are currently being analyzed for radiocarbon dating, sedimentology, geochemistry, and palynology. Pollen and plant spore assemblages are being used as a paleoclimate proxy to reconstruct mean annual precipitation, but also mean annual temperature, and the temperature of the coldest and warmest months. Paleoclimatic reconstruction will utilize the Climatic Amplitude Method and other methods.

Initial palynological results from Buck Pond sediments, ranging from approximately 250 to 5,100 years before present, reveal pollen assemblages consistently dominated by Pinus and Quercus pollen, suggesting a broadly similar paleoenvironment from the mid-Holocene to present, as observed in the field in late 2021 during drilling. Pollen from aquatic vegetation is also present, mainly Myriophyllum (water milfoil) and Nuphar (water-lily). Less abundant terrestrial pollen and plant spores in the assemblage include Alnus, Amaranthaceae, Asteraceae, Carya, Caryophyllaceae,

Myrica, Poaceae, Ulmus, and others. Non-pollen palynomorphs in the assemblages include fungal spores, lacustrine algae, freshwater dinoflagellates, and palynomorphs of unknown affinity. Palynological sample processing and analysis is currently in progress, to be followed with statistical and paleoclimatic investigation and integration with sedimentological and geochemical results.

Keywords: Holocene; southeastern United States; paleolimnology; paleoclimatology; Pacific North American Pattern; El Niño Southern Oscillation

Date: August / Agosto 10

Time: 11:50-12:10

Aragón-Moreno. Stingless bee Melipona beecheii food storage in suburban areas: when pollen type matter

A. A. Aragón-Moreno^a

^aEl Colegio de la Frontera Sur, Chetumal, México;

In the Yucatan peninsula, Mexico, meliponiculture is considered a legacy of the ancient Maya culture, and stingless bees honey and other products are well recognized for their nutritional and medicinal properties. Nevertheless, the growing urbanization, habitat degradation, and the loss of interest in peasants´ descendants force the meliponiculture to suburban areas, where older people and women can manage the bees. Here we present the pot-pollen palynology of a “jobón”, the traditional beekeeping method used by Mayan communities in the Yucatan peninsula, after 15 years of un-managed bee colonies. Our results show the Melipona beecheii pollen preferences, foraged in sub-urban secondary vegetation older than 25 years. Few pollen types composed the majority of pollen storage, showing the potential for beekeeping in sub-urban environments. Weekly pollen loads samples are being collected to compare them with stored pollen and to know whether the collected pollen is the preferred pollen in the area or it is a survival strategy when other common pollen types are unavailable. The findings would allow a better understanding of how Melipona beecheii manages their pollen reserves in sub-urban areas and how Mayan beekeepers can improve the pollen sources around the meliponary.

Keywords: Melipona beecheii; stingless bee pot-pollen, sub-urban Meliponiculture, Native bees’ palynology

Date: August / Agosto 8

Time: 14:40-15:00

di Pasquo. Can fluorescence be helpful to discriminate between indigenous taxa of Carboniferous age from those reworked of Mid-Upper Devonian rocks?

M. di Pasquo^a

^aLaboratorio de Palinoestratigrafía y Paleobotánica, CICYTTP-CONICET-ER-UADER, Dr. Materi y España S/N, Diamante (E3105BWA), Entre Ríos, Argentina

Terrestrial spores and pollen grains and phytoplankton of fresh- to marine water environments may exhibit bright yellow to weak orange, red and brown colors of autofluorescence. When fluorescence is good usually associated to well- preserved specimens, it is useful for their morphologic characterization, whereas the lack of fluorescence reveals preservational effects linked to taphonomic history. Concerning the recycling of palynomorphs deposited in a new active sedimentary cycle due to erosion of previous sedimentary rocks, they are useful in deciphering base-level variation, diastrophism, and provenance. Their recognition must be based on accurate taxonomic identification and more probable stratigraphic range. In this work, autofluorescence of palynomorphs is analyzed in samples of the Late Famennian of USA bearing indigenous Retispora lepidophyta and compared with samples from the Carboniferous of Bolivia and northern Argentina in which indigenous and Devonian reworked taxa (including R. lepidophyta) are found together. Standard palynologic method is applied using HCl (25%) and HF (40%), distilled water for neutralization of residues, and 10 μm and 25 μm meshes for sieving. The effect of oxidation on fluorescence is also tested, and for this purpose selected residues were oxidized with HNO₃ (3 minutes) and ammonia. Another objective is to compare the performance of fluorescence in slides mounted with different media (e.g. jelly-glycerin, Trabasil NR2, Cellosize/Entellan, Canadian Balsam, Norland NOA60, glycerin sealed with paraffin, and water for temporary slides). The microscopic analysis was performed using a light microscope Leica DM500 bearing a fluorescence device (LED lamp, filter block for fluorescein ca. 450 nm). Pictures of palynomorphs were taken with an Amuscope 14 Mp video camera and its software. This study revealed that R. lepidophyta exhibit autofluorescence colors from yellow to orange up to black (canceled) independently of its origin (indigenous or reworked, I-R). Also, in general, from the slides analyzed herein, phytoplankton species yielded lighter colors with higher intensity than monosaccate pollen grains and spores, in this order and beyond their I-R nature. The results confirm previous studies in which parameters such as the original composition of the exine of terrestrial and aquatic palynomorphs, as well as their source and taphonomic history affect autofluorescence. Moreover, I-R palynomorphs do not exhibit significant changes of fluorescence in slides mounted with non-oxidized and oxidized portions of the same residue. Concerning the performance of different mounting media for fluorescence analyses, the present comparison confirms that glycerin is one of the best media, non-fluorescent Cellosize and Norland (permanent slides), and water (temporary slides). The jelly-glycerin is a very used medium for mounting permanent slides in many countries due to is cheap, and easy to get and prepare, although it has green color of fluorescence, higher than that of Trabasil. Despite their fluorescence, the main trouble is that many or most palynomorphs are not adhered to the upper surface of the coverslip, so their fluorescence is not well-observed or is hidden by both media.

Keywords: Autofluorescence, indigenous and reworked palynomorphs, mounting media, palynologic methodologies

Date: August / Agosto 8

Time: 13:50-14:40

Francois et al. The UPLA pollen reference collection. Achievements and challenges

J.P.Francois^a, C. Quinteros^a, P. Hernández^a, I. Schneider^b & P. Ramírez^C

^aLaboratorio de Geografía Ambiental y Palinología (Lab GAP-UPLA), Departamento de Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile; ^bLaboratorio de Dendrocronología y Estudios Ambientales, Instituto de Geografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile; ^CLaboratorio de Botánica, Herbario VALPL, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile.

The University of Playa Ancha (UPLA) pollen reference collection is the result of a collective work between science, arts and community. The collection was created under the supervision of the VALPL Herbarium of the University of Playa Ancha, and today has 67 modern pollen samples from representative plant species of Central Chile sclerophyllous ecosystems living in La Campana-Peñuelas Biosphere Reserve, Chile – UNESCO. The samples represent local populations of trees and herbs, geographically identified and mapped, collected during its flowering seasons. Laboratory analyses include digital photography of acetolysed pollen grains at different views and z levels, obtained with an optical microscope Cytation 5. Also, SEM images were obtained with a Hitachi SU 3500, providing new and relevant information for a more accurate pollen characterization but also giving us the keys into arts of nature. During the pandemy and quarantine, one of the laboratory activities was compile the data in a pollen catalog, and simultaneously the design of an exposition. Online workshops were conduced, in order to share with local communities the experience of discover the beauty of pollen grains and create local pollen landscapes and collections from representative ecosystems or locations. Finally, the recent invitation to collaborate in scientific-social initiatives by means the analysis of corbicular pollen from apiaries located in Central Chile (30°-38°S), represent a new challenge for the laboratory but also an opportunity. Also the construction of a digital platform to make accessible the palynological collection to the community in general.

Keywords: pollen Digital and SEM photography; La Campana-Peñuelas UNESCO Biosphere Reserve; Central Chile sclerophyllous ecosystems; University of Playa Ancha

Francois et al. Palinoteca UPLA. Logros y desafíos

J.P.Francois^a, C. Quinteros^a, P. Hernández^a, I. Schneider^b & P. Ramírez^C

^aLaboratorio de Geografía Ambiental y Palinología (Lab GAP-UPLA), Departamento de Ciencias y Geografía, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile; ^bLaboratorio de Dendrocronología y Estudios Ambientales, Instituto de Geografía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile; ^CLaboratorio de Botánica, Herbario VALPL, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile.

En el presente poster, presentamos los resultados y experiencias tras la creación y puesta en marcha de la Palinoteca de la Universidad de Playa Ancha (Palyno-UPLA). Entre los productos se destaca la digitalización de muestras polínicas mediante un microscopio óptico de última generación (Cytation 5) e imágenes SEM (Hitachi SU 3500). Las muestras corresponden a especímenes representantes de la flora de Chile Central (n=67) las cuales fueron obtenidas durante diferentes campañas de terreno coincidentes con los periodos de floración de diferentes poblaciones de especies nativas. Así también, se han incorporado muestras provenientes del Herbario VALPL de la Universidad de Playa Ancha. Adicionalmente, se ha comenzado trabajar con polen corbicular de colmenares también presentes en Chile Central, con el objetivo de caracterizar su origen botánico. Finalmente, durante la pandemia se realizaron diversas actividades centradas en la difusión y que pretendieron vincular a la comunidad con la labor que se realiza en el laboratorio. Para esto, se realizaron talleres online en la cuales se invitó e instruyó a la comunidad como realizar colectas fin de crear palinotecas que representaran la flora local. El resultado fue alentador, por cuanto participo un número importante de personas de diferentes edades y no vinculadas necesariamente al quehacer científico, dando cuenta del interés general de las comunidades en referencia a capturar la belleza de los granos de polen. En la actualidad se trabaja en la creación de una plataforma digital que permita poner a disposición del público en general de las imágenes y datos referentes a la colección palinológica.

Palabras clave: palinoteca; Chile Central; SEM; comunidad y territorio.

Date: August / Agosto 8

Time: 15:20-15:40

Gualteros. Approach to the morphology of spores of the genus SPHAGNUM in high Andean forests

J.M Gualteros^a

^aUniversidad Incca de Colombia, Bogotá, Colombia

Palynological studies in plants have focused mainly on pollen morphology in angiosperms. On the other hand; the study of propagative structures in bryophytes is somewhat more scarce. Worldwide, only four studies of spores for the Sphagnaceae family are known, due to the fact that their importance has been focused on the ecology and taxonomy of the gametophyte, leaving aside one of the structures that is also very important for these studies and of which other aspects can be inferred in various areas; among which is paleoecology. For this reason, this research project aims to describe the morphology of the spores of the genus Sphagnum. For which field trips were made to the Agroparque Los Soches, Une and La Paz. Once the samples were treated, the Erdtman acetolitic technique was performed; In addition, the plates were assembled and, later, the description of the spores was carried out using a microscope with a 1000x objective for the measurements and observations of the characters. The spores of this genus have a triplet-shaped lesion, some have the presence of the perispore, others have escabrada ornamentation on the exine and; two characters not previously mentioned by the authors known as Kyrtomen and Labrum were found. In addition, the size of these structures ranges between 20 and 30um. From the above it is concluded that the morphological diversity of the spores is highly differentiated in the different morphotypes collected, for this reason these studies allow knowing the species to which they belong with the description of said structures, and in this way they attribute to the study of spores fossils in different sediments.

Keywords: Sphagnum, spore, trilete, kyrtomen, polar

Gualteros. Aproximación a la morfología de esporas del género SPHAGNUM en bosques alto andinos

J.M Gualteros^a

^aUniversidad Incca de Colombia, Bogotá, Colombia

Los estudios palinológicos en plantas se han enfocado principalmente en la morfología del polen en angiospermas. Por otra parte; el estudio de estructuras propagativas en briofitos es un tanto más escaso. A nivel mundial se conocen a penas cuatro estudios de esporas para la familia Sphagnaceae, debido a que se ha enfocado su importancia en la ecología y taxonomía, del gametofito, dejando de lado una de las estructuras también muy importantes para estos estudios y de las cuáles se puede inferir otros aspectos en diversas áreas; entre las que se encuentra la paleoecología. Por tal motivo este proyecto de investigación tiene como objetivo describir la morfología de las esporas del género Sphagnum. Para lo cual se realizaron salidas de campo al Agroparque los Soches, Une y La paz. Una vez las muestras fueron tratadas se les realizó la técnica acetolitica de Erdtman; además se hizo el montaje de las placas y, posteriormente se realizó la descripción de las esporas utilizando para las mediciones y observaciones de los caracteres un microscopio en objetivo de 1000x. Las esporas de este género cuentan con una lesura en forma de trilete, algunas cuentan con la presencia del perisporio, otros tienen ornamentación escabrada en la exina y; se encontró dos caracteres no mencionados anteriormente por los autores conocidos como Kyrtomen y Labrum. Además, el tamaño de dichas estructuras oscila entre las 20 y 30um. De lo anterior se concluye que la diversidad morfológica de las esporas es altamente diferenciada en los diferentes morfotipos colectados, por tal motivo estos estudios permiten saber la especie a la que pertenecen con la descripción de dichas estructuras, y de esta forma atribuyen al estudio de esporas fósiles en diferentes sedimentos.

Palabras clave: Sphagnum, espora, trilete, kyrtomen, polar

Date: August / Agosto 8

Time: 14:20-14:40

O'Keefe. Melissopalynology without acetolysis: the pros and cons of enzymatic and KOH-based processing techniques

Jennifer M.K. O’Keefe^a

^aDepartment of Physics, Earth Sciences, and Space Systems Engineering, Morehead State University, Morehead, KY USA.

Melissopalynology is an established science in much of the world and reliant upon traditional, acetolysis-based processing techniques for extraction of easily-recognized pollen from honey samples. This technique is advantageous in that it results in relatively rapid results, however, can be highly destructive to fragile pollen, and has a relatively high risk-assessment associated with it. Plant biologists and palynologists explored multiple less-risky and less-damaging methods in the early 2000’s, however, no direct comparison was made for honey samples. This comparison was completed in collaboration with Vaughn Bryant and students in 2017-2018 and is presented here for the first time. Enzymatic methods using cellulase and pectinase are safer and less destructive, but do not always produce clean preparations. These preparations can be improved through judicious short-term use of a 5% KOH treatment. Use of 10% KOH treatment alone sometimes results in exine damage. In both cases, prepared grains are generally somewhat smaller than those prepared using acetolysis.

Keywords: Enzymes, Cellulate, Pectinase, KOH, Melissopalynology

Date: August / Agosto 9

Time: 9:20-9:40

Paredes and Bryant. Pollen analysis of honey from the Peruvian Amazon

Rossana Paredes^a and Vaughn M. Bryant^b†

^aDepartamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Perú; ^bAnthropology Department, Texas A&M University, College Station, USA.

Melissopalynology is useful to determine the floral content and the geographical origin of honey. The great botanical diversity of the Amazon allows bees to produce honey that has an important value in the Peruvian culture. However, pollen analysis and labels that provide information on honey content are scarce; therefore, people do not know what types of honey they are consuming. For this reason, we carried out a melissopalynological study to analyze the pollen content of 14 samples of honey from Selva Alta and Selva Baja of the Peruvian Amazon. A total of 40 pollen types from 28 families were identified and most of the samples were multifloral. Pollen from Fabaceae, Asteraceae and Citrus was very frequent, while Myrciaria dubia, Trema and Paullinia were frequent in the samples. Bombax, Gouania and Mimosa pollen were rare in the samples. Pollen concentration values ​​per 10 g of honey ranged from very rich to very poor. Most of the floral sources identified in honey are related to taxa that are traditionally used for medicinal purposes. Bioactive compounds in the nectar of these plants may be producing the "healthier" properties that people associate with Amazonian honeys in Peru. This pollen study provides important information on the floral preferences of the bees and honey content, which can be used by traditional beekeepers and the public in general.

Keywords: melissopalynology, pollen, honey, Peru, Amazon

Paredes y Vaughn. Análisis del contenido polínico de mieles de la Amazonía peruana

Rossana Paredes^a y Vaughn M. Bryant^b†

^aDepartamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Perú; ^bAnthropology Department, Texas A&M University, College Station, USA

El análisis melisopalinológico es útil para determinar el contenido floral y el origen geográfico de la miel. La mega diversidad botánica de la Amazonía permite que las abejas produzcan miel de gran valor en la cultura peruana. Sin embargo, los análisis de polen y las etiquetas que brindan información sobre el contenido de miel son escasos; por lo tanto, las personas no saben qué tipos de miel están adquiriendo y consumiendo. Por esta razón, realizamos un estudio melisopalinológico para evaluar el contenido polínico de 14 muestras de miel de Selva Alta y Selva Baja de la Amazonía peruana. Se identificaron un total de 40 tipos de polen de 28 familias y la mayoría de las muestras fueron multiflorales. El polen de Fabaceae, Asteraceae y Citrus fue muy frecuente en las muestras, mientras que Myrciaria dubia, Trema y Paullinia se encontraron frecuentes en las muestras. El polen de Bombax, Gouania y Mimosa fue poco frecuente en las muestras. Los valores de la concentración de polen por 10 g de miel variaron de muy rico a muy pobre. La mayoría de las fuentes florales identificadas en la miel están relacionadas con taxones que se utilizan tradicionalmente con fines medicinales. Los compuestos bioactivos del néctar de estas plantas pueden estar produciendo las propiedades "más saludables" que las personas asocian con las mieles amazónicas en Perú. Este estudio de polen proporciona información importante sobre las preferencias de origen floral de las abejas y sobre el contenido de miel, que pueden utilizar los apicultores tradicionales y el público en general.

Palabras clave: melisopalinología; polen; miel; Perú; Amazonía.

Date: August / Agosto 9

Time: 9:40-10:00

Warny et al. Pollination ecology and effect of invasive species Elaeagnus angustifolia on honey bee foraging behavior

Sophie Warny^a,b, Joshua Campbell^c , Natalie West^c

^aDepartment of Geology and Geophysics, Louisiana State University, Baton Rouge, LA, USA; ^bMuseum of Natural Science, Louisiana State University, Baton Rouge, LA, USA; ^cPest Management Research Unit, USDA ARS NPARL, Sidney, MT 59270 USA.

Here we present the results of a pollination and palynological study designed to understand pollinator foraging behavior in a rural area in Montana that is characterized by a strong presence of freely occurring and planted specimens of Elaeagnus angustifolia L., the Russian olive tree. Despite the commonality of Russian olive within the western half of the United States, its pollination ecology has not been explored. We conducted (1) an insect exclusion experiment, (2) timed flower visitor observations, and (3) honey bee corbicular pollen analysis. The insect exclusion experiment demonstrated that Russian olive seed production is substantially increased via pollen transport by insects. During floral visitor surveys, honey bees (Apis mellifera) were the dominant floral visitor, comprising over 80% of all insect visitation to Russian olive flowers. We collected 75 honey bee foragers and removed corbicular pollen between June 10 and 25 2021, from four different sites, located north and south of Sidney, Montana. Results indicate that, Elaeagnus angustifolia is by far the most abundant type of pollen foraged by the bees throughout the study area, at all four sites, most of the days, most of the times targeted. Other types foraged include Chenopodiaceae/Amaranthaceae, Plantago, Poaceae, Rubus occidentalis, Salix, Asteraceae (ragweed type), Berberis, Juniperus, Quercus, and Trifolium/Melilotus.

Our data suggests that honey bees are highly attracted to Russian olive flowers, exhibit flower constancy, and act as a main pollinator. It is worth noting that Elaeagnus angustifolia and Apis mellifera are both Eurasian in origin; thus, it is possible that the honey bee may be the plant’s natural pollinator. It is also clear that, during Russian olive bloom periods, honey bees may be poor pollinators of other simultaneously blooming crops or native plants. The minimal flower visitation by other insects suggests that Russian olive is not attractive to native insects and, thus, provides minimal resources to native pollinators.

Keywords: Palynology; corbicular pollen; foraging; honey bees; entomology

Date: August / Agosto 9

Time: 10:00-10:20

Caballero and Jaramillo. RGraphCor: a tool to perform Graphic Correlation

D. Caballero Rodríguez^a and C. Jaramillo^a

^aSmithsonian Tropical Research Institute, Panama City, Panama

RGraphCor is an intuitive toolkit built in R (a language and environment for statistical computing and graphics) that we have developed to perform Graphic Correlations, a well-known biostratigraphic method. In 1986, Kenneth Hood developed a program in MS-DOS named GraphCor to perform Graphic Correlation, that he maintained during many years and now it is available to the public at no cost. Unfortunately, the software hardly runs in the modern computing systems, therefore, we decided to replicate GraphCor in a modern platform that runs within the R environment, compatible with the most widespread operative systems (IOS and PC), and it is open-source and cost-free.

The package consists in six main functions:

1) graphcor : Correlates and plots two stratigraphic sections and their content.

2) gc_screen: Displays an html plot to easily explore the data.

3) reloc: Try and compares different lines of correlation (LOC).

4) gc_extend: Extends the ranges of occurrences of the events in the reference section.

5) border_rm: Detects and marks in the plot events too close to the limits.

6) gc_summary: Summarizes the information from Composite Sections.

RGraphCor also includes additional functions to assist the users to formatting their data to optimize the analyses and avoid errors.

The software allows the use of different formats for the input, and it is capable to correlate events from different sources such as cores, drillings, and outcrops with different measurement units (e.g. feet and meters) and temporalities (comparing wells with outcrop sections). The final output is an automatically adjusted composite section that is ready to be compared with new sequences, making the process accumulative. Thus, a master stratigraphic sequence can be built by iteratively feeding it with different sequences to include more and more relevant stratigraphical events, and spanning wider time periods, always preserving the original data.

We hope this package will facilitate and promote the application of the powerful biostratigraphic method that is the Graphic Correlation.

Keywords: graphic correlation; biostratigraphy; line of correlation, composite section.

Date: August / Agosto 10

Time: 14:40-15:00

Jaramillo. Digital Palynology

Carlos Jaramillo^a

^aSmithsonian Tropical Research Institute, Panama City, Panama

jaramilloc@si.edu

The study of pollen and spores started more than a century ago and provides the fundamental basis to understand vegetation changes through time, date sedimentary rocks through biostratigraphy, and model plant evolution among many other applications. Since its origin, palynology has relied on the manual count of pollen and spores using a microscope. This is a process that requires a long time, years of training, and produces data that is not fully reproducible. The advent of new robotic tools that can digitize complete microscope slides and the fast development of neural network algorithms have provided the timing for Palynology to enter a new era in data generation and analysis. We are developing a training set of neotropical pollen to be used in a neural network that will assist pollen counts and identification. The developments produced here could be applied to multiple research questions where pollen can be used from paleoecology and paleoclimate to pollination biology and honey production.

Date: August / Agosto 9

Time: 8:50-9:20

Stephenson. Palynology and outcrop analogue studies for reducing uncertainty of reservoir heterogeneity in carbon capture and storage

M.H. Stephenson^a

^aGeoscience Consulting, Nottingham UK

Carbon capture and storage (CCS) is an option for reducing emissions to the atmosphere. Provisional conclusions from palynology and outcrop analogue studies suggest that these two techniques combined can contribute to understanding and predicting geological heterogeneity in subsurface formations. The use of these techniques shows how science developed to understand oil and gas extraction can be re-invented to help in the injection and underground management of CO₂.

CO₂ will be injected as far as possible in geological conditions that encourage slow migration, dissolution and precipitation, and/or stratigraphic trapping. The balance they may be sought is one between injectivity and presence of enough heterogeneity to facilitate solubility trapping. An example is the Sleipner CO₂ storage facility, the longest running facility for CO₂ storage. Repeat seismic surveys alongside specially tuned seismic has detected layers of rock with high CO₂ saturation – where the CO₂ has accumulated below thin sub-seismic mudstone layers creating bright spots within the reservoir. In the Utsira, mudstone layers could be been seen as problems for injection – perhaps making less of the reservoir available to injection, but also have proved useful in slowing down upward migration allowing more time for reactions to take place dissolving CO₂ and leading to more long term storage through carbonation. Thus the low permeability layers (baffles) promote ‘solubility trapping’ leaving the overlying seal (the physical trap) to do less of the work of confining the CO₂.

Recent use of palynology in understanding the geometry of mudstones has been developed through study of the Upper Permian fluvial Umm Irna Formation. This formation is 70m thick and outcrops for 40 km north to south along the Jordanian Dead Sea coast

Around 30 individual mudstone units within the Umm Irna Formation, both large and small, were sampled for their spores and pollen with the objective of determining whether mudstone lateral persistence (baffle continuity) could be predicted by palynological content. Overall the argillaceous units revealed pollen and spores that varied a lot but generally fell into two categories. The first group was found in laterally persistent argillaceous units like migrating point bars or flood deposits associated with the main river channels. This was high in diversity, containing a wide variety of Permian pollen and spores that probably represent a regional snapshot of the vegetation on the floodplain and the higher ground around.

The second assemblage from smaller argillaceous units like oxbow and channel plugs was of lower diversity with high proportions of one or two local palynomorphs, and also the spores of green algae (mainly zygospores) that usually indicate water bodies that are drying up..

The reason for this distinction is not completely clear, and more work needs to be done on other similar fluvial successions both ancient and modern, however it seems likely that the different assemblages relate to the way that palynomorphs are transported. Although saccate palynomorphs (e.g. Falcisporities, Alisporites, Taeniaesporites) can be distributed by wind, their main transport is by flowing water. Thus a depositional environment more closely associated with an active river channel that drains a large hinterland through its network of tributaries is more likely to contain a diverse assemblage of palynomorphs. Those associated with abandoned channels, particularly where a waterbody is drying up is more likely to contain palynomorphs like zygospores (e.g. Quadrisporites; where green algae start to dry up) and purely local palynomorphs from plants very close to the water body – possibly growing just around it.

The distribution and lateral continuity of mudstone baffles will be obvious in outcrop, but the key is transferring what has been learned from the outcrop to the subsurface. If detailed palynology work is done, preferably on core on fairly closely spaced boreholes, it should be possible to distinguish a horizontal baffle in a borehole from a narrower mudstone unit with less baffle potential. This could be very useful in providing information on geological heterogeneity in advance of CO₂ injection in CCS projects.

Keywords: palynology, heterogeneity, carbon capture and storage.

Date: August / Agosto 9

Time: 8:30-08:50

Adkin and Zavada. Monitoring Air quality in the Permian Basin during Covid-19 and West Texas drought

Adkin^a, S.B. and Zavada^b

^aDepartment of Geosciences, University of Texas Permian Basin University, 4901 E. University Blvd., Odessa, TX 79762 USA; ^bDepartment of Biology, University of Texas Permian Basin University, 4901 E. University Blvd., Odessa, TX 79762 USA

Air quality is an ever-increasing issue in the United States. Air pollution is one of the leading causes of lung and heart disease, especially in vulnerable populations. The advent of Covid-19 in late 2019 and a severe drought beginning in West Texas in early 2020 and still ongoing has created unusual circumstances with regard to air quality and public health in the Permian Basin. Our study has been monitoring airborne Pollen, Spores, other organically derived particles (e.g. plant trichomes and phytoliths), Volatile Organic Compounds (VOCs), SO2 and Particulate Matter (1, 2.5, and 10-micron PM). The pandemic caused a ripple effect throughout the oil field that eventually led to halting of many oilfield operations while at the same time increasing flaring of natural gas. Although there were increases in the release of VOCs, especially methane, during this time our fixed monitors detect no notable increase. This phenomenon is attributed to highly local nature of flaring and methane plume emissions. As severe drought has developed over the last two years, pollen and spores have decreased in abundance caused by the reduction in plant growth and flowering due to the drought. Pumpjack pads and the lack of vegetation has exposed more barren ground in the region leading to an increase in airborne particulate matter. Although daily averages of PM are at acceptable EPA levels, days with wind speed above 10 knots (a common event in the Permian Basin), can cause severe dust events, which last only a few hours, that are well above acceptable levels of PM. These events can cause acute distress in people with respiratory disease. Although our regional air quality may be characterized as good, there are severe episodic events for airborne dust and proximity to oil field operations can also significantly affect people sensitive to VOCs and SO2.

Keywords: pollen, spores, VOCs, SO2, particulate matter, oilfield operations, air pollution, flaring.

Date: August / Agosto 9

Time: 11:20-11:40

Nuñez Otaño et al. Análisis preliminar de palinomorfos no polínicos: una investigación experimental con implicancias forenses (La Picada, Entre Ríos, Argentina)

N. B. Nuñez Otaño^a, E. V. Perez-Pincheira^a, C. Trujillo^b, M. Bertos^b, M. Bordi^b, and G. Fagúndez^b

^aLaboratorio de Geología de Llanuras. Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante; CICYTTP (CONICET- Prov. ER- UADER), Argentina; ^bLaboratorio de Actuopalinología- CICYTTP (CONICET-Prov. ER-UADER), Diamante, Entre Ríos, Argentina

corresponding author: noeliabnunez@gmail.com

La micología contribuye como disciplina a varias otras, pero su aplicación en la ciencia forense ha ido en aumento en los últimos años. A partir del trabajo con intervalos post-mortem, evidencia de rastros y perfiles de suelo, es evidente que es necesario intensificar la investigación experimental para usar hongos en contextos forenses. Se presenta el primer trabajo experimental en una hipotética escena del crimen que rastrea el sitio de depósito de restos humanos en un área natural protegida cerca de un arroyo en la localidad de La Picada (Entre Ríos) centrándonos en palinomorfos no polínicos (PNP), particularmente hongos. La composición floral y el régimen climático del sitio de estudio corresponden a un bosque xerófilo caducifolio abierto relativamente bajo, con un estrato arbustivo pobre y un sotobosque de plantas herbáceas bajo un clima subtropical-templado. Las muestras se tomaron durante la primavera del sedimento del sendero elegido para realizar el experimento; así como suelo acumulado en la suela de los zapatos y con el método de la cinta de los hombros, muslos y tobillos sobre la ropa de un sujeto después de caminar 1 hora por el sendero. Las muestras se procesaron siguiendo protocolos estándar utilizados en palinología forense adaptados para este experimento. Los PNPs identificadas fueron las esporas de hongos como las más abundantes, seguidas de teca de amebas, diatomeas y nematodos. Las características de las esporas fúngicas y la ecología correlacionada con la vegetación del sitio de estudio y la ecología general de los PNPs fueron útiles para delimitar el sitio de estudio en cuanto a su clima y composición floral. Los sedimentos contenían una mayor riqueza de hongos y otros PNPs que se encuentran comúnmente en el suelo, la hojarasca y los restos de madera (cf. Sphaerodes, Glomus sp., Tetraploa aff. aristata, Bispora aff. antennata, Criconemoides sp., quiste cf. Lecythium asini, entre otros). Las muestras de tobillos, muslos y hombros mostraron una menor riqueza de hongos, pero se correlacionaron con los que crecen sobre la vegetación (en árboles y arbustos) presente en el sitio de estudio aproximadamente a la misma altura en el sendero (Drechslera/Bipolaris, Melanomma sp., Meliola sp, cf. Venturia, entre otros). Hasta el momento, estos resultados mostraron que los hongos se correlacionan con la composición floral local y el clima regional, siendo herramientas valiosas con aplicaciones forenses. Sin embargo, existe la necesidad de continuar trabajando en este tipo de investigación experimental utilizando los PNPs como representantes confiables para una aplicación concreta en ciencias forenses para esclarecer la escena del crimen.

Palabras clave: Hongos, Ecología de hongos, palinomorfos no-polínicos, ciencias forenses

Nuñez Otaño et al. Preliminary analysis of non-pollen palynomorphs: An experimental research work with forensic implications (La Picada, Entre Ríos, Argentina)

N. B. Nuñez Otaño^a, E. V. Perez-Pincheira^a, C. Trujillo^b, M. Bertos^b, M. Bordi^b, and G. Fagúndez^b

^aLaboratorio de Geología de Llanuras. Facultad de Ciencia y Tecnología, Universidad Autónoma de Entre Ríos, Sede Diamante; CICYTTP (CONICET- Prov. ER- UADER), Argentina; ^bLaboratorio de Actuopalinología- CICYTTP (CONICET-Prov. ER-UADER), Diamante, Entre Ríos, Argentina

corresponding author: noeliabnunez@gmail.com

Mycology contributes as a discipline to several others but its application in forensic science has been increasing. From working with postmortem intervals, trace evidence, and soil profiles are evident we need to intensify experimental research to use fungi in forensic contexts. We present the first experimental work at a hypothetical crime scene tracing the site of human remains' deposition in a protected area (relatively low spiny trees, shrubs, and an understory of herbaceous plants) near a creek in La Picada location (Entre Ríos) focusing on non-pollen palynomorphs (NPP), particularly fungi. The floral composition and climatic regime of the study site correspond to a shrubby forest with grassland and ferns under a subtropical-temperate climate. The samples were taken during the spring from sediment from the trail chosen to conduct the experiment, soil accumulated in the sole of the shoes, and with the tape method from a subject's shoulders, thighs, and ankles after walking 1 hr on the trail. The samples were processed following standard protocols used in forensic palynology adapted for this experiment. The NPPs identified were fungal spores as more abundant followed by thecate amoebas, diatoms, and nematodes. Fungal spore traits and ecology correlated with the vegetation of the study site and NPPs' general ecology were useful to delimitate the site of study regarding its climate and floral composition. Sediments held a higher species richness of fungal spores and other NPPs commonly found in soil, litter, and wood remains (cf. Sphaerodes, Glomus sp., Tetraploa aff. aristata, Bispora aff. antennata, Criconemoides sp., cyst cf. Lecythium asini, among others). Samples from ankles, thighs, and shoulders showed less fungal richness but correlated with those growing over the vegetation present at the study site roughly at the same height in the walking path with more fungal species growing on trees and bushes (Meliola sp, cf. Venturia, Melanomma sp., Drechslera/Bipolaris, among others). So far, these results showed that fungi correlate with local floral composition and regional climate being valuable tools with forensic applications. Although, there's a need to continue working on this kind of experimental research using NPPs as reliable proxies for a concrete application in forensic sciences like elucidating the crime scene.

Keywords: Fungi; fungal ecology; NPP; forensic science.

Date: August / Agosto 9

Time: 13:30-13:50

Soares et al. Contribution to the pollen morphology in Bauhinia L. and Schnella Raddi species (Cercidoideae, Fabaceae) from forest patches in Southeastern Brazil

E.L. Soares^a,*, L.A.D.C. Landia^a, C.N. Souza^a and E.C. Gasparino^b

^aDepartment of Biology, Faculty of Philosophy, Sciences and Letters, Graduate Program on Comparative Biology, University of São Paulo (USP), ZIP 14040-901, Ribeirão Preto, São Paulo State, Brazil; ^bDepartment of Biology, Laboratory of Plant Morphology and Palynology, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), ZIP 14884-900, Jaboticabal, São Paulo State, Brazil.

* Corresponding author: eduardolsoares@usp.br

Cercidoideae has a wide geographic distribution in Brazil, with its most representative genera Bauhinia and Schnella. The present study aimed to describe the pollen morphology of Bauhinia and Schnella from forest fragments in southeastern Brazil and to contribute to the morphology description of these genera and species of Cercidoideae. The description of the pollen morphology of 21 species was carried out, being 13 species of Bauhinia and eight species of Schnella. Pollen materials were obtained from exsiccates deposited in Brazilian herbaria. Pollen grains were acetolyzed, measured (n = 25) and photographed to obtain qualitative and quantitative data. Quantitative pollen grain data were examined by descriptive and multivariate analysis. The pollen grains of the studied species showed variation in size (medium to very large), shape (oblate to oblate spheroidal or prolate), type and detail of ectoaperture (3-porate, 3- or 5-colpate, 3-colporate, angulaperturate, planaperturate or fossaperturate, very short to very long and narrow to very large ectoaperture, tapered or rounded at the polar ends, membrane of the ectoaperture with ornamentations or not, with or without margo, constricted or note) and endoaperture (lolongate, circular, or lalongate endoaperture, costate or not), exine ornamentation (areolate, striato-reticulate, microreticulate heterobrochate or homobrochate, and reticulate heterobrochate or homobrochate ornamentation) and types of supratectal elements (with bacula, clavae, gemmae and verrucae, or without supratectal elements).

Quantitative data, mainly diameter measurements, allowed the separation of the Bauhinia and Schnella genera in the multivariate analysis. From the data obtained and the pollen variations observed in the species already analyzed, we can describe Cercidoideae and Bauhinia and Schnella genera as Eurypalinos.

Keywords: Palynology, Phanera, Cerrado, Eurypalynous.

Date: August / Agosto 9

Time: 11:00-11:20

Torres and Mapes. Paleodrainage Evolution of Northern South America and its Impact on Exploration Success in the Guyana Basin

Vladimir Torres Torres and Russell W Mapes^a

^aGlobal New Opportunities, Exploration & New Ventures Frontier, ExxonMobil, Upstream Company

vladimir.torres@exxonmobil.com

Since 2015, the Guyana Basin has become one of the most exciting hydrocarbon provinces in the world and a key asset in ExxonMobil’s portfolio thanks to oil discoveries in the Stabroek Block, offshore Guyana. New evidence indicates that uplift in the Northern Andes played a significant role in the sedimentary history of the Guyana Basin. Recognition of Devonian and Andean palynoflora within thick Messinian to recent mass transport complex (MTC) deposits in the Guyana Basin attest to their distant provenance, and comparable palynology results from industry wells in the Amazon Fan (Hoorn et al., 2017) suggest a shared history. Modern sedimentation on the Guianas shelf is dominated by long- and along-shore bypass of fine-grained Amazon River derived sediment, and little material makes it into the deep-water Guyana Basin at present. The sudden and voluminous late Miocene onset of MTC accumulation in the Guyana Basin and contemporaneous growth of the Amazon Fan is temporally consistent with continental-scale drainage reorganization that occurred onshore that connected Andean sedimentation to the Atlantic margin for the first time. We hypothesize that MTC sedimentation was triggered by sudden availability of large volumes of fine-grained sediments to the Guianas margin coupled with Neogene high frequency and high amplitude sea level fluctuations (Milankovitch scale cycles) that allowed rapid accumulation of unstable sediment at the shelf-slope break. Frequent, possibly semi-continuous, slope failures led to thick MTC accumulations in the Guyana Basin down-dip. Our preliminary analysis indicates that without the combination of these factors, sedimentation rates in the Guyana Basin would have remained low throughout the Neogene and the basin-wide hydrocarbon system evolution would have been dramatically different.

Keywords: Guyana Basin, Andean flora, MTC, Amazon Fan,

Date: August / Agosto 9

Time: 10:40-11:00