USGS Visual Identifier
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Geologic Unit: Oranda

No current usage.
(†Oranda Formation (PA,VA,WV), †Oranda Formation of the Trenton Group (WV) replaced with part of Stickley Run Member of Martinsburg Formation. See Stickley Run.)

Ordovician, Middle

Geologic Province:
Appalachian basin

Areal Extent:

Type Locality:
Type section: along State Highway 55 about 2.7 mi S. 40 W. of Oranda and somewhat less than 0.5 mi west of U.S. Route 11 in north environs of Strasburg, Shenandoah Co., north-central VA. Named from hamlet near Strasburg (Cooper and Cooper, 1946).

Unit Name History:
Named (Cooper and Cooper, 1946).
Extended into WV and PA (Kay, 1948).
Revised to part of Trenton Group (Cardwell and others, 1968).
Overview (Rader and Biggs, 1976).
Biostratigraphic dating (Harris and others, 1994).
Abandoned (Epstien and others, 1995).

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