Memoir #09

Lauck W. Ward and George W. Andrews

Excellent fossiliferous exposures of the Calvert, Choptank, and St. Marys Formations occur along the Chesapeake Bay and its tributaries in Maryland and Virginia. Stratigraphic cross-sections were constructed along the Chesapeake Bay and Patuxent, Potomac, and Rappahannock Rivers which allow correlation of the various beds from the Chesapeake Bay to the updip sections near Richmond, Virginia. The nomenclatural history of the Calvert, Choptank, and St. Marys and their members and beds is discussed and the units are redescribed. Stratotype localities are selected and correlation and age of the beds is documented. We reject the terms Popes Creek Sand and Dunkirk because they are on units included in the Fairhaven Member by Shattuck (1904). We suggest discarding the terms Calvert Beach Member. Bed 14/15/16 is included in the Plum Point Member of the Calvert Formation. The Conoy Member is assigned to the basal St. Marys Formation and two new members, the Little Cove Point and the Windmill Point, are formally introduced as subdivisions of the St. Marys.