Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada

Bruce R. Wardlaw; Dora M. Gallegos; Valery V. Chernykh; Walter S. Snyder

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USGS · 70160391

Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada

Bruce R. Wardlaw·Dora M. Gallegos·Valery V. Chernykh·Walter S. Snyder

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Abstract

The lower Part of the Garden Valley Formation yields two distinct conodont faunas. One of late Asselian age dominated by M esogondolella and Streptognathodus and one of Artinskian age dominated by Sweetognathus with Mesogondolella . The Asselian fauna contains the same species as those found in the type area of the Asselian in the southern Urals including Mesogondolella dentiseparata , described for the first time outside of the Urals. Apparatuses for Sweetognathus whitei , Diplognathodus stevensi , and I dioprioniodus sp. are described. The Garden Valley Formation represents a marine pro-delta basin and platform, and marine and shore fan delta complex deposition. The fan-delta complex was most likely deposited from late Artinskian to lateWordian. The Garden Valley Formation records tremendous swings in depositional setting from shallow-water to basin to shore.

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Source-reported bounding extent: 39.3° to 41° latitude; -116.3° to -115.9° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Bruce R. Wardlaw, Dora M. Gallegos, Valery V. Chernykh, Walter S. Snyder. 2015. Early Permian conodont fauna and stratigraphy of the Garden Valley Formation, Eureka County, Nevada. https://pubs.usgs.gov/publication/70160391

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