Research
My research involves a variety of techniques such as cathodoluminescence (CL), scanning and transmission electron microscopy (SEM and TEM), X-ray diffraction, Fourier Transform Infrared Spectroscopy (FT-IR), and stable isotope analysis (particularly strontium, carbon and oxygen). Not all of my work is in the lab; I do extensive fieldwork around the world - my field sites have ranged from the tops of mountains to the bottom of the ocean, from deserts to volcanoes to caves. My current field areas include western Mongolia, Germany, Belgium, and a variety of field sites (including caves) in the southern Appalachians.
Current Research
Oceanic anoxia in the Late Devonian.
Much of my current research includes work with Dr. Johnny Waters (Appalachian State University) and Dr. Peter Königshof (Senckenberg Natural History Museum) and a variety of international geoscientists and students on geochemical changes preserved in sediments during mass extinctions. Our team is known as the DAGGER (Devonian Anoxia, Geochemistry, Geochronology, and Extinction Research) group, and our field sites are in China, Mongolia, Vietnam, Iran, the USA and throughout Europe. Much of our work has stemmed from UNESCO's International Geoscience Programme (IGCP) Project 596 on Mid-Paleozoic Climate and Biodiversity. For more information about the DAGGER group, visit http://devonian.appstate.edu, and you can follow us on Instagram at (@365millionyears).
(below) IGCP 596 Field Workshop in southwestern Mongolia, August 2014. Photo courtesy of Johnny Waters.
Geomicrobiology of caves in the southern Appalachians.
My other primary research direction is interdisciplinary geomicrobiology research with Dr. Suzanna Bräuer in the Department of Biology, characterizing the sedimentology and microbial ecology of sites with biologically mediated Mn-oxides in southern Appalachian caves. We also look at human impact on cave systems using a variety of tracers. For more information about our geomicrobiology research group, visit http://geomicrobiology.appstate.edu.
Reactive fluid flow, ore deposition, and biomineralogy in the southern Appalachians.
I also use multiple geochemical tracers to determine the fluid flow history and origin of Mn-oxide deposits in Cambrian rock units in the southern Appalachians. This work is in conjunction with Daniel Doctor and Ryan McAleer of the USGS, as well as other faculty and students at Appalachian State University.
Crystallographic orientation, order/disorder, and fluid-rock reactions in replacement dolomite
I have recently returned to the rocks of the Dolomites (where I did my graduate work) to investigate the role of crystallography, trace element geochemistry, and order/disorder on replacement dolomitization processes, using electron backscatter diffraction (EBSD).
Past research:
Engare Sero Footprint Site, Tanzania.
I was also involved in the Engare Sero Project with Dr. Cynthia Liutkus-Pierce to help fingerprint the source of the volcanic ash that has preserved early hominid footprints in Tanzania. New research on the project includes an investigation of the evolution of mineral chemistry in Si-deficient and carbonatite ash layers from the Ol Doinyo Lengai volcano; this work has been publicized by National Geographic, the Washington Post, and many others.
Hydrothermal vent systems at 9°50'N East Pacific Rise
Prior to coming to Appalachian State, I spent much of my time at sea, on the R/V Atlantis, studying hydrothermal vents located at spreading ridges on the seafloor. My research explored fluid-rock interactions in altered basalt at the 9°50'N East Pacific Rise (EPR) Integrated Study Site (ISS).
Triassic hydrothermal vent systems in the Latemar Dolomite, northern Italy
My graduate work in the Latemar carbonate buildup, northern Italy explores the "Dolomite Problem," a classic sedimentology problem, from a metamorphic petrologist's point of view. It uses reactive transport theory to interpret the chemical, isotopic, and mineralogic effects of fluid-rock reactions in a (very) low-temperature metamorphic setting, one that is analogous to modern diffuse effluent systems in hydrothermal vent fields at mid-ocean ridges.
