UPPER CRETACEOUS PLANKTIC FORAMINIFERAL BIOSTRATIGRAPHY AND DETERMINATION OF THE SANTONIAN/CAMPANIAN BOUNDARY IN GONGZA, TINGRI, TIBET
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
The Cretaceous is a period of frequent occurrence of major geological events such as oceanic anoxia and biological extinction, and also an important period of global warming. Therefore, the study of the Cretaceous is of great significance to the study of the systematic evolution of the earth in geological history, especially the co-evolution relationship between organisms and environment. The complete stratigraphic sequence of the Upper Cretaceous is preserved in Gongza, Tingri, Tibet. In this paper, well-preserved planktic foraminiferal fossils obtained from the samples of the Gangba Cunkou Formation and Zongshan Formation of the Upper Cretaceous are studied, and 22 species of 8 planktic foraminiferal genera are identified. Four foraminiferal zones are recognized as follows, from bottom to top: Dicarinella asymetrica, Globotruncanita elevata, Globotruncana ventricosa, and Radotruncana calcarata. According to foraminifera fossils, the age of Upper Cretaceous strata of Gongza section should be from the late Cretaceous Santonian-Campanian, and the Santonian/Campanian boundary should be located at the boundary between the Dicarinella asymetrica Zone and the Globotruncanita elevata Zone.
