2020 Joint Section Meeting

Rebecca Kavage Adams, Maryland Geological Survey, rebecca.adams@maryland.gov; William Junkin, Maryland Geological Survey, william.junkin@maryland.gov; David K. Brezinski, Maryland Geological Survey, david.brezinski@maryland.gov.

Description: This trip traverses Maryland’s Eastern Piedmont and will cover the Baltimore mafic complex and the Baltimore terrane, including the Baltimore gneiss domes, Setters quartzite, and Cockeysville marble. Westward, Potomac terrane ultramafics, metadiamictite, and greywacke will be examined. The final stop will be within the Pleasant Grove shear zone.

F.R. Ettensohn, University of Kentucky, fettens@uky.edu; Clay Seckinger, University of Kentucky, clayseckinger@icloud.com.

Description: The trip examines a glaciogenic diamictite of approximately the same age in the Hampshire, Rockwell, and Price Formations of Maryland and West Virginia. Stratigraphy and palynology provide environmental and temporal frameworks. Analyses of igneous clasts suggest that the glaciers sampled accretionary highlands during early phases of the Neoacadian orogeny.

Callan Bentley, Northern Virginia Community College, cbentley@nvcc.edu; Christopher Roemmele, West Chester University, croemmele@wcupa.edu.

Description: This field trip examines D.C.’s metasedimentary rocks. Likely Neoproterozoic in depositional age, they were metamorphosed and intruded by igneous plutons during Late Ordovician Taconian orogenesis. The mountain belt’s roots were exposed by erosion by the Cretaceous, when sediments of the Coastal Plain were deposited. Later, reverse faulting ruptured this nonconformity.

Christopher Swezey, U.S. Geological Survey, cswezey@usgs.gov; Emily L. Brent, U.S. Geological Survey, elbrent96@gmail.com; Grant D. Colip, U.S. Geological Survey, gcolip@usgs.gov.

Description: This trip presents the geology and geomorphology of the Trout Rock Caves (Hamilton Cave, Trout Cave, New Trout Cave) in the Silurian-Devonian Helderberg Group (Pendleton County, West Virginia), with emphasis on how stratigraphic and structural settings have influenced cave location and morphology. The trip entails some crawling in mud.

Bill Burton, U.S. Geological Survey, bburton@usgs.gov; Steve Schindler, U.S. Geological Survey, sschindl@usgs.gov.

Description: A one-day trip across the Blue Ridge geologic province in northern Virginia focusing on the Mesoproterozoic, Neoproterozoic and Paleozoic geologic evolution of the northern Blue Ridge anticlinorium.