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Middle Campanian ammonites and inoceramids from the Wolfe City Sand in northeastern Texas

W. A. Cobban·W. J. Kennedy
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Abstract

The middle Campanian Wolfe City Sand in northeastern Texas yields a distinctive ammonite and inoceramid fauna with Patagiosites sp., Placenticeras sp., Hoplitoplacenticeras ( Hoplitoplacenticeras ) minor n. sp., Baculites mclearni Landes, 1940, Trachyscaphites spiniger (Schlüter, 1872) porchi (Adkins, 1929), Inoceramus ( Cordiceramus ) azerbaidjanensis Aliev, 1939, and I. ( Endocostea ) balticus Boehm, 1907. The last-named four species allow a direct correlation with the Baculites mclearni zone of the Western Interior of the United States. The base of this zone has been dated at 79.9 ± 3.2/79.2 ± 1.6 Ma on the basis of K/Ar determinations on biotite from a bentonite. Inoceramus azerbaidjanensis is also known from the Campanian of the U.S.S.R. in Azerbaidjan (where the species was first described), western Turkemenia, Georgia, the northern Caucasus, the Crimea, and Donbass.

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BibTeXRIS

W. A. Cobban, W. J. Kennedy. 2016-05-20. Middle Campanian ammonites and inoceramids from the Wolfe City Sand in northeastern Texas. https://doi.org/10.1017/s0022336000021181

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