Student Research Projects

SEM Analysis of Samples from the Aquia Formation Outcrop in King George County, Virginia

Student Lewis Myers '14
Faculty Mentor(s)
Department Earth and Environmental Sciences
Course BIO 400: Scanning Electron Microscopy (SEM)


The Aquia formation of Virginia and Maryland has been studied by geologists since the 19th Century. Outcrops of this formation appear in several places around the Chesapeake Bay in both states (Shifflett, p.3). This rock layer is primarily composed of glauconite, quartz, calcareous clay, and a substantial amount of mica. The calcite clay functions as cement for the other particles in the hardened deposits (Shifflett, p.8). Deposits of similar compacted glauconitic greensands are believed to have accumulated in the near shore margins of the oceans during the transition between the Paleocene and Eocene epochs. The generation of these minerals comes from detrital biotite or other parent materials, by marine weathering in neritic environments under anoxic conditions; mainly in unconsolidated sandstone (

The scope of this project was to determine if the chemical properties of rock samples obtained from the Aquia Formation matched the text book descriptions of the predominant minerals found in these deposits.