沉积与特提斯地质2018，Vol.38Issue(2)：3-13,11.
羌塘盆地沃若山地区上三叠统土门格拉组烃源岩沉积环境分析
Sedimentary environments of the Upper Triassic Tumengela Formation in the Woruo Mountain area in the Qiangtang Basin,Xizang
摘要
Abstract
This paper focuses on the study of the sedimentary environments of the source rocks from the Upper Triassic Tumengela Formation (T3t)in the Qiangtang Basin,Xizang,in the light of petrology,geochemistry and sedimentary facies analysis. The sedimentary environments of the source rocks in the Upper Triassic Tumengela Formation is assigned to the delta sedimentary facies. The enrichment of the hydrolytic elements,iron group elements,and the element Fe (Fe/Mn ratios)in the upper sandstones indicates the shallower river mouth to onshore environments. The values of CIA (63. 8-79),ICV (0. 52-1. 4)and Ga/Rb vs. K2O/Al2O3 diagrams show the moderate weathering under the semi-arid to semi-humid climatic conditions. The Sr/Ba ratios are all less than 1 (0. 09 to 0. 27),indicating the low-salinity and fresh continental sedimentary environments. The V,U and Mo contents also indicate the anoxic-suboxic water environments. The warmer and wetter climates are beneficial to the reproduction of organisms,while the anoxic-suboxic environments are not constructive to the enrichment of organic matter. The low TOC values of 0. 76% to 1. 46%(mean value is 1. 04%)have disclosed that the source rocks should be assigned to the medium-quality source rocks in the study area.关键词
羌塘盆地/上三叠统土门格拉组/地球化学特征/沉积环境Key words
Qiangtang Basin/Upper Triassic Tumengela Formation/geochemical signature/sedimentary environment分类
天文与地球科学引用本文复制引用
冯兴雷,付修根,谭富文,陈文彬..羌塘盆地沃若山地区上三叠统土门格拉组烃源岩沉积环境分析[J].沉积与特提斯地质,2018,38(2):3-13,11.基金项目
羌塘盆地金星湖-隆鄂尼地区油气资源调查项目(DD20160159) （DD20160159）
