Usage:
Barley Mill Gneiss of Wilmington Complex (DE)
Geologic age:
Early to Middle Ordovician
Type section, locality, area and/or origin of name:
Type section [composite]: two localities near Tatnall School, north of community of Sedgley Farms, Wilmington North 7.5-min quadrangle, New Castle Co., DE; (1) on south side of Barley Mill Road at intersection with road to school, Lat. 39 deg. 46 min. 16 sec. N., Long. 75 deg. 36 min. 40 sec., W., and (2) on west side of pond, south of Barley Mill Road, east of Tatnall School, Lat. 39 deg. 46 min. 01 sec. N., Long. 75 deg. 36 min. 40 sec., W. Origin of name not stated by authors, but probably named from Barley Mill Road (Plank and others, 2000).
AAPG geologic province:
Atlantic Coast basin
Piedmont-Blue Ridge province
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).