When: March 29, 2017, 2:00 pm
Location: 3rd Floor Orchard View Room , Discovery Building
Contact: 608-316-4401, email@example.com
Earth’s biogeochemical evolution: a view from the upper crust
Earth’s surface chemistry is controlled, at the most fundamental level, by mass exchanges occurring between the surface environment and the lithosphere. Although this fact has been recognized for more than 100 years, it has generally been assumed that sediment deposition and recycling by erosion are in balance, resulting in a dynamic steady state that requires evolutionary innovations or environmental perturbations to affect major change. Here, I use Macrostrat, a database designed to quantitatively describe the geographic and chronostratigraphic distribution, thickness, and composition of rocks in Earth’s upper crust, to provide new constraints on the surviving mass and age of sedimentary deposits. The time series of sedimentary rock quantity as a whole does not exhibit the expected signature of erosion, but it does bear many similarities to geochemical and biological proxy records that are indicative of major changes in Earth’s surface environment. Causal mechanisms for empirical similarities between proxy records for Earth’s surface conditions and the sedimentary rock record are explored, along with implications for the maintenance of complex life.
All qBio sponsored talks take place on Wednesdays at 2:00 p.m. in the 3rd floor Orchard View room of the Discovery Building unless otherwise noted. Talks are open to the public. Access to the room is via the elevator behind Aldo’s Cafe in the Northeast corner of the building.