- Usage in publication:
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- Ward Mountain Trondhjemite*
- Modifications:
-
- Named
- Geochronologic dating
- Dominant lithology:
-
- Tonalite
- AAPG geologic province:
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- Sierra Nevada province
Summary:
Named for exposures at Ward Mountain. Type locality is Ward Mountain [approx 37 deg 11'N, 119 deg 38'W, Madera Co, CA]. Is 2nd youngest formally named unit of Fine Gold Intrusive Suite (new). Forms two subcircular plutons in SW part of figure map. Rocks previously called leucotonalite of Ward Mountain (Bateman and Busacca, 1981) and plagiogranite of Ward Mountain (Stern and others, 1981). Bulk of rock is fine-grained and gneissic with granoblastic texture as seen in thin section. Intrudes Bass Lake Tonalite (new); is intruded by Knowles Granodiorite (new). Age is Early Cretaceous based on U-Pb age of 115 Ma (Stern and others, 1981).
Source: GNU records (USGS DDS-6; Menlo GNULEX).
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 ([ ]).