Keck Geology Consortium

Award Date: October 2011

Summary

David Gillikin, Assistant Professor of Geology, has been awarded a $40,000 grant through the Keck Geology Consortium to support his project "Biogeochemical carbon cycling in fluvial systems from bivalve shell geochemistry -- using the modern to understand the past."  The proposed research builds on an ongoing collaborative project between Union College, Denison University and the Ohio State University, and now includes faculty from the University of North Dakota. Additionally, six undergraduate students will join the faculty in the proposed research activities.

Abstract

Freshwater mussel shells offer a unique record of past environmental conditions in streams, rivers and lakes. They can produce up to several centimeters of carbonate shell per year offering one of the highest temporal resolution proxies of terrestrial environmental and climatic change. Accordingly, freshwater mussels have proved useful for reconstructing important environmental variables such as precipitation patterns (e.g., development of a monsoonal climate; Dettman et al. 2001), mountain uplift (Dettman & Lohmann 2000; Fan & Dettman 2009), and changes in river discharge (Ricken et al., 2003; Versteegh et al., 2009, 2011).

This research has three main goals:
1) Reconstruct patterns of intra-annual growth from freshwater mussels grown in under natural and controlled conditions using high-resolution records of environmental variability.
2) Calibrate the fidelity and resolution of geochemical proxies through comparison of shell geochemistry with high-resolution records of environmental variation.
3) Reconstruct fluvial biogeochemistry before and after the K-T mass extinction event.

The project will take place in three phases. In Phase 1 (~7 days), we will collect fossil freshwater mussels from various sites in Montana from sediments bracketing the Cretaceous-Paleogene (K-T) Boundary. We will be travelling in the backcountry of Montana, camping as we go. In Phase II (~10 days), we will conduct calibration experiments on living and recently killed mussels at the Columbus Zoo Mussel Research Center. These experiments will be designed to help decode the environmental signals preserved in the fossil shells. In Phase III (~10 days) we will conduct analytical work on modern and fossil shells. These analyses will take place at both Denison (Ohio) and Union (New York).