Sampling Sediment from a Terrace Deposit Above the James River, VA

USGS Collaborators from Virginia Division of Geology and Mineral Resources and College of William and Mary sample sediment from a high-level terrace deposit about 200 feet above the James River in Cumberland County, Virginia, for age dating using the terrestrial cosmogenic nuclides (TCN) method.  This work was a collaborative effort between the Virginia Department of Mines, Minerals, and Energy and the U.S. Geological Survey, funded by a grant from the National Earthquake Hazard Reduction Program.  The trench was excavated across the surface projection of the Lakeside fault, a prominent regional fault in the CVSZ with potential evidence of Cenozoic fault reactivation.  GPR traverses and geologic mapping identified the location of the trench.  Data revealed that this terrace about 1 million years old, but no definitive evidence for earthquake deformation was found in the trench.