U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS

National Geologic Map Database

NGMDB

Geologic Unit: Chesapeake

Usage:

Chesapeake Group (DE*,DC*,MD*,NC*,VA*)


Subunits:

(alphabetical): Bacons Castle Formation (NC,VA), Bethany Formation (DE), Calvert Formation (DE*,MD*,NC,VA*), Cat Hill Formation (DE-subsurface), Choptank Formation (DE,MD*,VA*), Chowan River Formation (NC*,VA*), Eastover Formation (MD*,NC*,VA*), Old Church Formation (MD*,VA*), St. Marys Formation (DE*,MD*,VA*), Yorktown Formation (MD*,NC*,VA*).


Geologic age:

Tertiary (late Oligocene to late Pliocene)*


Type section, locality, area and/or origin of name:

Type area: areas adjacent to Chesapeake Bay (Darton, 1891).


AAPG geologic province:

Atlantic Coast basin*


NGMDB

For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).

Find Us:

twitter

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
Supported by the National Cooperative Geologic Mapping Program
URL: http://ngmdb.usgs.gov
Page Contact Information: Personnel
Page Last Modified: Tue Jun 3 16:03:52 2014