- Usage in publication:
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- Merrill Formation
- Modifications:
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- Areal extent
- AAPG geologic province:
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- Permian basin
Summary:
Merrill Formation mapped in the Davis Mountains area, Jeff Davis Co, west TX in the Permian basin. Consists of latite porphyry, hard, reddish brown, weathers with pitted surface, brown to yellowish brown, locally fine- to coarse-grained, vitric-lithic tuff at top. Thickness is about 130 ft. Pinches out rapidly eastward. [Unclear on Correlation of Map Units if Merrill is part of Vieja Group.] Shown as above Sheep Pasture Formation. [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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