- Usage in publication:
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- Brooks Mountain Formation
- Modifications:
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- Areal extent
- AAPG geologic province:
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- Permian basin
Summary:
Brooks Mountain Formation mapped in the Brooks Mountain area of the southern Davis Mountains, Jeff Davis Co, west TX in the Permian basin. Consists of porphyritic trachyte, with colorless to gray alkali feldspar phenocrysts, aphanitic to very fine grained in lower part, fine grained in upper part, weathers grayish brown; forms steep, locally vertical cliffs. Maximum thickness is 985 ft. [Unclear on Correlation of Map Units if Brooks Mountain is part of Vieja Group.] Shown as above Goat Canyon Formation and below Petan Basalt. [Author states that correlation of volcanic rocks from area to area on Marfa sheet is uncertain--little attempt is made to correlate between areas. The rocks are described by area.] Of Oligocene age. Geologic map.
Source: GNU records (USGS DDS-6; Denver GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
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