USGS Visual Identifier
National Geologic Map Database logo GEOLEX database

Geologic Unit: Cape Ann

Cape Ann Granite (MA*)
Cape Ann Complex (MA)

Ordovician, Late*
Silurian, Early*
Geologic Province:
New England province*

Areal Extent:

Type Locality:
Type area: Cape Ann, Essex Co., northeastern MA (Shaler, 1890).

Beverly Syenite and Squam Granite of Cape Ann Complex (MA)

Unit Name History:
First used (Shaler, 1890).
Overview (Toulmin, 1964).
Age modified (Zartman and Marvin, 1971).
Revised (Goldsmith and others, 1982).
MA State Geol. Map usage (Zen and others, 1983).
Revised; Isotopic dating (Wones and Goldsmith, 1991).
Revised (Dennen, 1991).
Overview (Hon and others, 1993).

Note: If you need more information, please contact Nancy Stamm (
Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys.

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

Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]).

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
Database project personnel
Last modified: 15-Jan-2013