Weathering as a Climate Indicator in Alluvial Systems
Inferring climatic conditions from Earth’s “deep-time” (pre-Cenozoic) geologic record is challenging. Together with my geochemist colleague Dr. Megan Elwood-Madden here at OU, we are devising new ways to assess climatic parameters by examining the record of rock weathering in a variety of climates by sampling sediments from a wide array of modern fluvial systems. We have completed sample collections in hot-arid, hot-humid, cold-arid and cold-humid regions, including the desert southwest, Puerto Rico, Antarctica, and Norway. We have also ventured closer to home– the Wichita Mountains of Oklahoma. Preliminary results are challenging our views on the way rocks weather under different climatic regimes; owing to the strong connection between rock weathering and atmospheric CO2, these results have implications for understanding how carbon cycles through the Earth system.