贵州中南部早三叠世沉积演化

Sedimentary Evolution of Early Triassic in Middle-South Guizhou

通过对贵州修文—广西天峨地区早三叠世地层剖面测制和相序解析,并对其相的确定和划分。重点从各地层组的岩性组合、生物组合、顶底界线入手,进行综合对比研究,进而达到相区划分。得出研究区早三叠世早期广海陆棚沉积环境演化为碳酸盐缓坡沉积环境;末期向镶边碳酸盐台地沉积环境过渡,而罗甸板庚一带为孤立台地沉积环境。同时建立起研究区早三叠世两个三级层序。

By stratum section mapping and sequence analyses of early Triassic in Xiuwen of Guizhou and Tiane of Guangxi, its facies are determined and zoned. According to lithology assemblage, biography assemblage, top and bottom boundary, it＇ s compared and studied, then the facies are zoned. It can be known that the sedimentary environment evolution of continental shelf in early Triassic in the target area is carbonate gentie slope sedimentary environment, translates to edging carbonate platform sedimentary environment finally, but Bangeng area in Luodian is isolated platform sedimentary environment. Meanwhile, two 3 - level sequences of early Triassic are set up in the target area.