- Usage in publication:
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- Big Chief basalt member (informal)
- Modifications:
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- Original reference
- Dominant lithology:
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- Basalt
- AAPG geologic province:
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- Sierra Nevada province
Summary:
Pg. 1453-1464. Big Chief basalt member of Lousetown Formation. Older than Tahoe City flow (new). Age of Bald Mountain olivine latite (new) relative to Big Chief basalt difficult to ascertain, but Bald Mountain may be slightly younger. Big Chief basalt flow blocked Upper Truckee Canyon drainage and brought about deposition of Fir Crags gravel. At least 20 flows (or groups of flows) recognized in Truckee area, north of Lake Tahoe. Nine flows (or groups of flows) are named and given informal member status in Lousetown formation. Age is early Pleistocene.
Mapped in vicinity of settlement of Big Chief, Placer Co., northeastern CA. [Named from Big Chief Summit, Truckee area, in sec. 15, T. 16 N., R. 16 E., Tahoe City 7.5-min quadrangle, Placer Co., northeastern CA.]
Source: US geologic names lexicon (USGS Bull. 1350, p. 65); supplemental information from 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 ([ ]).