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- Usage in publication:
-
- Lakeview Mountain tonalite*
- Modifications:
-
- Named
- Dominant lithology:
-
- Tonalite
- Quartz diorite
- AAPG geologic province:
-
- Peninsular Ranges province
Summary:
Occurs in Elsinore, San Jacinto, and Ramona 30' quads. Underlies most of Lakeview Mountain in Elsinore quad, Riverside Co, CA. Lakeview Mountain tonalite replaces name Lakeview quartz-hornblende diorite of Dudley (1935) and Lakeview tonalite of Merriam (1941). Is uniform rather coarse-grained nearly white rock with scattered black plates of biotite and stout prisms of hornblende. In contact with Bonsall tonalite; character of contact indicates Bonsall tonalite intrudes Lakeview Mountain tonalite but the two probably not very different in age. Map legend gives age as Cretaceous.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- Lakeview Mountain tonalite
- Modifications:
-
- Areal extent
- AAPG geologic province:
-
- Peninsular Ranges province
Summary:
Lakeview Mountain tonalite found in north-central part and on western edge of Santa Ysabel 15-min quadrangle, San Diego County, California. Appears to be younger than Green Valley tonalite. Contacts with rocks other than Green Valley poorly exposed; hence, no definite age determination could be made.
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 ([ ]).