Architecture and evolution of an Early Permian carbonate complex on a tectonically active island in east-central California

Calvin H. Stevens; Robert T. Magginetti; Paul Stone

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USGS · 70160383

Architecture and evolution of an Early Permian carbonate complex on a tectonically active island in east-central California

Calvin H. Stevens·Robert T. Magginetti·Paul Stone

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Abstract

The newly named Upland Valley Limestone represents a carbonate complex that developed on and adjacent to a tectonically active island in east-central California during a brief interval of Early Permian (late Artinskian) time. This lithologically unique, relatively thin limestone unit lies within a thick sequence of predominantly siliciclastic rocks and is characterized by its high concentration of crinoidal debris, pronounced lateral changes in thickness and lithofacies, and a largely endemic fusulinid fauna. Most outcrops represent a carbonate platform and debris derived from it and shed downslope, but another group of outcrops represents one or possibly more isolated carbonate buildups that developed offshore from the platform. Tectonic activity in the area occurred before, probably during, and after deposition of this short-lived carbonate complex.

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Stratigraphy Article

Source-reported bounding extent: 36.09349937380574° to 36.465471886798134° latitude; -117.82424926757811° to -117.29415893554686° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Calvin H. Stevens, Robert T. Magginetti, Paul Stone. 2015. Architecture and evolution of an Early Permian carbonate complex on a tectonically active island in east-central California. https://pubs.usgs.gov/publication/70160383

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