| Summary: | The Goodland/Comanche Peak Limestone, Kiamichi Formation and basal Duck Creek Limestones around Fort Worth Texas yield a limited number of cosmopolitan ammonite and inoceramid bivalve taxa that allow precise correlation with the sequence that has been used as a standard in northwest Europe. The upper part of the Goodland/Comanche Peak Limestones yields species of Dipoloceras that show the base of the Upper Albian substage, provisionally defined as the first appearance of D. cristatum (Brongniart, 1822), to lie within this unit. Brancoceras aff. cricki Spath, 1934, Mortoniceras (Deiradoceras) beloventer new species, and Actinoceramus cf. concentricus (Parkinson, 1819) parabolicus Crampton, 1996a, co-occurs with D. cristatum in the Comanche Peak Limestone. The Kiamichi Formation yields rare Mortoniceras (Mortoniceras) pricei (Spath, 1922), M. (Deiradoceras) prerostratum Spath, 1921, M. (D.) bipunctatum Spath, 1933, and Actinoceramus sulcatus (Parkinson, 1819) morphotypes that allow correlation with the European Hysteroceras orbignyi and Hysteroceras varicosum subzones of the Mortoniceras inflatum zone. The basal Duck Creek Limestone yields Mortoniceras (Deiradoceras) sp. and Hysteroceras cf. varicosum (J. de C. Sowerby, 1824), and can also be correlated with the varicosum zubzone.
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