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- Usage in publication:
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- Bufa formation, limestone
- Modifications:
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- First used
- Dominant lithology:
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- Limestone
Summary:
First used as one of eight formations in the Sierra de Los Lamentos, northern Chihuahua, MX. The lower four formations (Angela, Los Lamentos, San Vicente, and Bufa limestones) are separated from the upper four formations (Sonora, Tlaxcala, Buena Suerte, and Triste limestones) by the Sonora thrust fault. It is possible that the formations above the Sonora fault are simply a repetition of the section below the fault. Type not designated; name attributed to F. L. Ransome, derivation not stated. Overlies San Vicente limestone with gradational contact. Underlies Sonora limestone with thrust fault contact. Is light-gray with mottled light-pink, fossiliferous, ridge-capping limestone. Fossils include corals and gastropods; some listed. Thickness exceeds 1,500 ft. May correlate with Edwards limestone of Fredericksburg group on basis of lithology and fossils. Age is [Early] Cretaceous.
Source: GNU records (USGS DDS-6; Denver GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
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