摘要
西藏仲巴地区,下二叠统巨日浦组上段,以环叶菊石(Cyclolobus)为代表的菊石动物群,是我国继在西藏阿里地区(Diener,C.,1903)发现之后,又一新的发现。经研究包括3属3种,1个未定种(含新种1个)。即:Medlicottia sp., Propinacoceras cf. beyrichi Gemmellaro. Cyclolobus kraffti Diener, C. zhongbaensis Sheng(sp. nov.),时代为早二叠世晚期。环叶菊石(Cyclolobus)是环叶菊石科(Cyclolobidae)中进化最高阶段的代表,是早二叠世晚期的菊石带化石之一,和帝汶菊石(Timorltes)相当,但多见于印度洋沿岸,归于印度太平洋区(东特提斯区)。巨日浦组菊石的发现,对国内外地层对比及板块构造理论探讨具有一定意义。
The meterals presented in this paper were collected from Xizang (Tibet) during the 1:1, 000, 000-scals geological mapping (1980). The ammonoid fauna occurs in Juripu Formation at Jiongguo, NNE of Zhongba county. The elements described and illustrated in the present paper comprise Medlicottia sp., Propinacoceras cf. beyrichi Gemmellaro, Cyclolobus kraffti Diener, C. zhongbanensis Sheng (sp. nov.), which are of late Early Permian age. The genus Cyclolobus is a typical element of the East Tethyan Realm. It is a zone fossil corresponding to Timorites, but commonly occurring along the coast of the Indian Ocean.Based on the lithological and palaeontological characters, the Juripu Formation is divided into two members, the ammonoids occur in the Upper Member. The Upper and Lower Members of the Juripu Formation correspond to the Late Maokou and Qixia-Early Maokou stages respectively in southern China.For the description of new species, see text.
出处
《地质论评》
CAS
CSCD
北大核心
1989年第4期324-332,共9页
Geological Review
