Abstract

Three Late Cretaceous shale units cropping out in the northern Great Valley have been sampled for foraminiferal content. Approximately 2,500 ft. of section is represented in association with 1,500 ft. of sandstone. Ninety species of Foraminifera - 22 of which are new - are illustrated, described, and their stratigraphic ranges determined. One new name is proposed. Two distinctive faunas are recognizable, the division coinciding approximately with the Turonian-Senonian boundary. Arenaceous species constitute the greater number of individuals, while for stratigraphic purposes the Orbulinidae - especially the genus Globotruncana - are dominant in the Turonian, and they, with the Rotaliidae, are of greatest importance in the Senonian. Most of the species have been previously reported from the European and Gulf Coastal regions. An interpretation of the paleoecology indicates a sublittoral zone as the site of deposition for associated sediments. On the basis of foraminifers and diagnostic megafossils, the ages of the units are determined as middle Turonian, Coniacian, and Santonian.

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