My collaborators--Sierra Petersen and Allison Curley--and I have published a new article in the journal Geology this month. We report paleotemperatures from the North American interior during the peak of the mid-Cretaceous greenhouse, which is considered to be the hottest time on Earth for the past several hundred million years. The study analyzed the clumped isotopic compositions of calcite powders from fossil shells of oysters that inhabited the Western Interior Seaway of North America, and were collected by the late USGS paleontologist Bill Cobban. Find the article at Geology (or email me for a copy) and see it featured at the links below in popular science outlets thanks to coverage by Jim Erickson (University of Michigan).

https://www.sciencedaily.com/releases/2022/05/220510102839.htm

https://news.umich.edu/bali-like-temperatures-in-wyoming-fossils-reveal-tropically-hot-north-america-95-million-years-ago/

Citation

• Matthew M. Jones, Sierra V. Petersen, & Allison N. Curley; A tropically hot mid-Cretaceous North American Western Interior Seaway. Geology 2022; doi: https://doi.org/10.1131/G49998.1

Last week, I had the chance to present preliminary results about new cores recovered from the Agulhas Plateau during IODP Expedition 392 to a hybrid audience of the Geological Society of Washington at the historic Cosmos Club. Thanks to the GSW for the invitation and I look forward to attending more gatherings in the future!

The International Ocean Discovery Program (IODP) Expedition 392 team has arrived in Cape Town, South Africa. After a 1-week hotel quarantine, we will embark for two months at sea to core five sites on the Agulhas Plateau and in the Transkei Basin. These first sediment cores of the Cretaceous and Paleogene from this region will provide a window into a past geologic time of greenhouse warmth at southern high latitudes. We also hope to understand just how the massive volcanic Agulhas Plateau (the size of the U.S. states of Arizona or New Mexico) formed.

Follow along in real time for the ship's progress here:

https://joidesresolution.org/

Read about the full set of scientific objectives here:

http://iodp.tamu.edu/scienceops/expeditions/agulhas_plateau_climate.html

This month, I begin two-years of research and public outreach as a new Peter Buck fellow in the Department of Paleobiology at the Smithsonian National Museum of Natural History on the National Mall in Washington DC. Collaborating with curators Brian Huber, Gabriela Farfan (Mineral Sciences), and others at the museum, we will be reconstructing paleoclimate and paleoceanographic conditions utilizing the expansive invertebrate macrofossil collections of the Smithsonian. Be sure to send me a message on your next visit to the museum!

It was a pleasure to present a research talk for the Spring Geology colloquium series at Oklahoma State University this month and to have the chance to interact with students and faculty virtually. I look forward to visiting campus in person in the future!

I am excited to share that I have been selected to sail on IODP (International Ocean Discovery Program) Expedition 392 to core the Agulhas Plateau offshore South Africa in 2022! For my second IODP expedition, I will return to the shipboard position of Physical Properties and Downhole Logging specialist. Cores will be drilled from the Transkei Basin and Agulhas Plateau for the first time to study the origin of this submarine large igneous province and probe its influence on paleoclimate and paleoceanographic circulation in the Cretaceous and Paleogene. Learn more about the expedition at:

http://iodp.tamu.edu/scienceops/expeditions/agulhas_plateau_climate.html

After a tumultuous year of disruptions to research schedules, I am glad to be back in the SCIPP lab at the University of Michigan measuring new paleotemperature data. The latest samples targeted for analysis are Early Cretaceous invertebrate macrofossils. My collaborators and I hope to quantify temperatures during a greenhouse climate interval in geologic history by analyzing the carbonate clumped isotope geochemistry of the specimens.

Several of us from the Petersen lab group at U. Michigan recently presented our research findings in Cretaceous paleoclimatology and carbonate geochemistry at the virtual 2020 Geological Society of America (GSA) Fall Meeting. For abstracts and more details on the research, read more here: https://community.geosociety.org/gsa2020/home

Our new research article is now in press at the Geological Society of America Bulletin. The research reports new isotope geochemical measurements of shales (initial Os isotopes) and high-precision geochronology (40Ar/39Ar bentonite dating) from the U.S. Western Interior Basin. The data reconstruct the timing of massive volcanic activity during one of the most severe Phanerozoic ocean anoxic events ("OAE2"). It details the link between rapid CO2 emission and paleoceanographic feedbacks, as well as constrains the age of the Cenomanian-Turonian stage boundary. Read more here: https://doi.org/10.1130/B35594.1.