Stratigraphic Occurrence and Correlation of Early Tertiary Vertebrate Faunas, Trans-Pecos Texas: Agua Fria–Green Valley Areas

Abstract

ABSTRACT The Devil's Graveyard Formation, Agua Fria–Green Valley area of Brewster and Presidio counties, Texas, has produced the early Uintan Whistler Squat local fauna from the basal conglomerate and the lower member, the late Uintan Serendipity local fauna from the middle member, the early Duchesnean Skyline local fauna from the base of the Bandera Mesa Member, an early Chadronian unnamed local fauna from the Cotter channels, and the early Chadronian Coffee Cup local fauna from the middle part of the Bandera Mesa Member. Stratigraphic positions for and composition of the local faunas are given. Faunas from the Cotter channels and Montgomery bonebed are correlated with the Porvenir local fauna of the Vieja area. The Coffee Cup local fauna is correlated with the Airstrip local fauna of the Vieja area. K-Ar dates associated with each of the local faunas extend from 49.7 and 46.9 to 32.2 m.y. The Skyline local fauna lies above a date of 42.7 m.y. and beneath the Cotter channels and Montgomery bonebed. The s...