GEOLEX database Geologic Unit: Assabet Usage: Assabet Quartz Diorite (MA*) Age: Silurian* Geologic Province: New England province* Areal Extent: MA* Type Locality: Exposures on Hill 272 in northeast corner of Maynard. The main tongue-shaped mass of rock extends from Maynard northeastward into Concord quadrangle, north-central MA Named from exposures near Assabet River in town of Maynard (Hansen, 1956). Unit Name History: Named (Hansen, 1956). Age changed (Castle and others, 1976; Goldsmith and others, 1982). MA State Geol. Map usage (Zen and others, 1983). Overview (Wones and Goldsmith, 1991). Note: If you need more information, please contact Nancy Stamm (nstamm@usgs.gov). 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 URL http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html Database project personnel Last modified: 7-Jan-2007