My research focuses on the Cretaceous - Paleogene (K-Pg) mass extinction. I'm particularly interested in potential climate induced biotic effects around the boundary. Geochemistry, particularly stable isotope analysis of carbonates, is a useful tool for reconstructing the paleotemperatures of past environments. I have two study areas where the K-Pg boundary is present, the James Ross Basin on the Antarctic Peninsula, and the Hell Creek area in Montana.

A large ammonite (Anapachydiscus sp.) in Antarctica
James Ross Basin - I am working as part of a multi-institution research group examining the K-Pg boundary over three field seasons in Antarctica. The James Ross Basin is comprised of several islands off the northeast of the Antarctic Peninsula. This highly-expanded shallow marine section was deposited during the Late Cretaceous and Early Paleogene as a back arc basin during the uplift of the Antarctic Peninsula. Due to a minimal burial history, fossil shell material is extremely well preserved. Stable isotopic analysis of this shell material can be used to reconstruct the temperature of seawater, allowing the examination of climate changes through a stratigraphic section. Statistical analysis of invertebrate fossil occurrences over the same interval allows me to determine whether observed temperature changes correspond with paleobiological changes.

Hell Creek - The Hell Creek area is one of the most well studied K-Pg sections due to the common preservation of everyone's favorite fossils, dinosaurs. Less popular, but more interesting (to me anyway), are the well preserved freshwater bivalves found throughout this area. Due to variability in freshwater oxygen and carbon isotopes, traditional stable isotopic techniques have been less useful in terrestrial settings. Therefore I am employing a relatively new, but more technologically challenging, stable isotope method- clumped isotope thermometry - in order to reconstruct paleotemperatures here. I am spending three field seasons working with vertebrate paleontologists studying the evolution and extinction of mammals across the K-Pg boundary.