Pennsylvanian stratigraphy and biostratigraphy in the Cerros de Amado, Socorro County, New Mexico
— Spencer G. Lucas, Karl Krainer, James E. Barrick, Bruce D. Allen, and W. John Nelson


The Pennsylvanian section in the Cerros de Amado of Socorro County is as much as 744 m thick and consists of three formations of marine and mixed marine-nonmarine origin. At the base of the Pennsylvanian section, the Sandia Formation unconformably overlies Precambrian basement and is a 162 m thick cyclic succession of siliciclastic (notably quartzose sandstone and conglomerate) and carbonate (mostly coarse-grained bioclastic wackestone/packstone) strata. The overlying Gray Mesa Formation is 233 m thick and divided into three members: Elephant Butte Member (95 m of limestone and shale with a prominent 10 m thick sandstone bed near the base), Whiskey Canyon Member (35 m of mostly very cherty limestone), and Garcia Member (103 m of diverse limestone, conglomerate, sandstone, and shale). The overlying Atrasado Formation is up to 348 m of interbedded siliciclastics (mostly shale and arkosic sandstone) and varied limestones. Members of the Atrasado Formation (ascending) are Bartolo, Amado, Tinajas, Council Spring, Burrego, Story, Del Cuerto, and Moya. The lower Permian Bursum Formation overlies the Pennsylvanian section in the Cerros de Amado and is as much as 120 m of red-bed siliciclastics and limestones. Sparse fusulinid data and more extensive conodont records indicate the following ages: late Atokan (Sandia Formation), early Desmoinesian (most of the Gray Mesa Formation), late Desmoinesian (uppermost Gray Mesa Formation, Bartolo, and lowermost Amado members of Atrasado Formation), Missourian (most of Amado, Tinajas, Council Spring, and lower Burrego members of Atrasado Formation), and Virgilian (upper Burrego, Story, Del Cuerto, and Moya members of Atrasado Formation).

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Recommended Citation:

  1. Lucas, Spencer G.; Krainer, Karl; Barrick, James E.; Allen, Bruce D.; Nelson, W. John, 2022, Pennsylvanian stratigraphy and biostratigraphy in the Cerros de Amado, Socorro County, New Mexico, in: New Mexico Geological Society, 72nd Fall Field Conference, Sept. 2022, Socorro, New Mexico, Koning, Daniel J.; Hobbs, Kevin J.; Phillips, Fred M.; Nelson, W. John; Cather, Steven M.; Jakle, Anne C.; Van Der Werff, Brittney, New Mexico Geological Society, Field Conference, pp. 147-164.

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