鲁中地区早奥陶世早期头足类的发现

DISCOVERY OF THE EARLIEST ORDOVICIAN CEPHALOPODA FOSSILS FROM CENTRAL SHANDONG

摘要:

Abstract:

The cephalopoda fossils described in this paper were collected from the first member of the Zhifangzhuang Formation of Ezhuang, Zibo city and Xiaohuiquan of Juxianconnty, Shangdong Province. The discovery of Barnesoceras, Dakeoceras, Clarkoceras, etc. in the middle and upper parts of the first member of the Zhifangzhuang Formation is of great geologic significance becanse they are index fossils for the base of the Gasconadian Formation (Lower member of the Canadian )in North America. The age of Barnesoceras...