摘要
本文是在研究了本区地质构造背景为前提,采用现代沉积岩石学中岩石的分类命名(以突出岩石的环境),及生物生态相。并考虑了沉积岩石中保留微量元素的多少等多重相因素概念,讨论了二叠系三分后新建立的下二叠统(早二叠世即以(?)类Pseudoschwagerina带之始—Pamirina带之顶,牙形刺Streptognathodus elongatus-S.simplex带之始至Neostre-ptognathodus pequopensis带之始,菊石Properrites plummeri-Eoasianites subhaniei组合至Propinaceras simile组合,珊瑚主要为Kepingophyllum组合。将原阳新统划归中二叠统,乐平统划归上二叠统)沉积相。划分出四个沉积区,十个沉积(亚)相。即①盆地沉积区:包括盆地亚相,丘台亚相,陆棚亚相,斜坡亚相。②台地边缘区:为台地边缘礁、滩相。③台地沉积区:包括开阔海台地亚相(内含台地浅滩亚相,台内洼地亚相),半局限海台地亚相。④陆地边缘沉积区:滨岸沼泽相。根据各相区特点,建立起贵州早二叠世综合沉积模式。提出二叠纪海侵始于早二叠世晚期——羊场期初。
Based on the researches on the geological structure of the area,adopting the rock classification nomenclature of modern sedimentary petrology, with rock environment stressed, and biofacies and taking various facies with much or less trace element remaining in sedimentary rocks into consideration, this paper deals with the newly-formed LowerPer-mian series after the third division of Permian system, with Early Permian beginning from Fusulina, Pseudoschwagerina zone to Pamirina zone, Conodont Streptognathodus elongatus-S. Simplex zone to Neostreptognathodus pequopensis, Ammonoide Properrites plummeri--Eoasianites subhaniei assemblages to Propinaceras simile assemblages and with corals mainly being Kepingophyllum assemblages.
The original Yangxin series is considered to belong to Middle Permian series and Leping series considered to belong to the sedimentary facies of Upper Permian series. Four sedimentary areas and ten sedimentary facies have been divided:
Ⅰ. The basin sedimentary area includes basin subfacies, bioherm platform subfacies, shelf facies and slope facies.
Ⅱ. The platform margin sedimentary area includes reef and bank facies of platform margin.
Ⅲ. The platform sedimentary area includes open sea platform facies with shallow beach subfacies of platform and intraplatform depression subfacies and half-restricted sea platform subfacies.
Ⅳ. The continental margin sedimentary area belongs to beach swamp facies. Summing up the features of each facies stated above, a synthetical sedimentary model
of Early Permian in Guizhou can be established. This paper suggests the marine transgression of Permian begin in Early Permian, that is, in the early Yangchang period.
出处
《贵州地质》
1989年第2期123-132,共10页
Guizhou Geology
