Hominin Sites and Paleolakes Drilling Project

My dissertation work was part of HSPDP, an international effort to use lacustrine deep drill cores to reconstruct Plio-Pleistocene climate and answer pressing questions on the role of environmental change in driving human evolution. Lead by both paleoclimatologists and paleoanthropologists, the project successfully obtained six cores from East African basins famous for hominin fossils and archaeological artifacts.

As a member of the organic geochemistry team in HSPDP, I worked to produce leaf wax biomarker hydrogen and carbon isotope records from many of these lake cores. I have studied everything from long term million-year climate trends, to millennial-scale hydroclimate fluctuation. I implemented time series analysis tools to pick up statistically significant changes in environmental variability, periodicity, and trend, linking East African climate to global-scale climate transitions. I currently have one paper published, two in review, and two in preparation that have come out of my dissertation work. Please view my CV or contact me with any questions or to request the PDF.

In addition to the biomarker isotope work as part of HSPDP, I have aided in the production of age models, time series analyses of grain size and other lithological indicators, and GDGT work.

North African Climate from ODP 966/967 Sapropels

Sapropels are dark, organic-rich layers in sediment that form in the Mediterranean Sea when intense North African rainfall flows from the Nile River basin and provides a freshwater cap to limit oxygenation of the deep sea. These layers have been used in astrochronological reconstructions to demonstrate their faithful response to precession and eccentricity cycles. Dr. Cassy Rose demonstrated that measuring leaf wax isotopes preserved in the ODP 966 and 967 cores from the Eastern Mediterranean Sea was a wonderful technique to quantify past climate to understand the strength of precession minima and maxima.

For my postdoc in the same laboratory, I will be measuring the hydrogen and carbon isotopic makeup of leaf waxes from each of the sapropel layers over the past ~4.5 million years. This, along with a precise astronomically-tuned age model, will allow us to better understand long term climate change, as well as eccentricity’s role in amplifying precession-driven monsoon systems.