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- Usage in publication:
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- Los Lamentos 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 Angela limestone. Underlies San Vicente limestone. Is light-gray mottled with pink, fine-grained, thick-bedded, fossiliferous limestone; abundantly fractured and traversed with veins of white calcite; breaks with rough conchoidal fracture. Abundant CAPRINA noted. Forms steep slopes and bold outcrops. Average thickness is 400 ft. Is correlated (together with Angela and San Vicente limestones) with the Trinity group of the Comanche series on basis of fossil fauna. 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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