Calcareous Nannofossils from the Niobrara Formation(Upper Cretaceous)and Pareoenvironments of the North American Western Interior Basin Part I:Nannofossil Assemblage Characteristics and Zonation
LIU Huai-bao1,D.K.Watkins2
1. Iowa Geological Survey, 109 Trowbridge Hall, lowa City, IA 52242, USA; 2. Department of Geoscience, University of Nebraska, Lincoln, NE 68588, USA
LIU Huai-bao1,D.K.Watkins2. Calcareous Nannofossils from the Niobrara Formation(Upper Cretaceous)and Pareoenvironments of the North American Western Interior Basin Part I:Nannofossil Assemblage Characteristics and Zonation[J]. J4.