Geochemical Characteristics and Organic Matter Enrichment of the Dongyuemiao Member Mudstone of Lower Jurassic in the Western Hubei-Eastern Chongqing
Guo Laiyuan
Zhang Shiwan
Xie Xinong
Li Zhongsheng
Huang Chuanyan
Chen Beichen
Abstract：The shale heterogeneity in different regions of China is the basic geological issue to be addressed urgently.However, the study of continental shale gas in the Sichuan basin is very weak.Based on analysis of the petrology and geochemistry of the Dongyuemiao member of lower Jurassic Ziliujing Formation in western Hubei-eastern Chongqing area, and combined with the logging curve, the vertical variation of geochemical characteristics and organic matter enrichment have been discussed.The results show that the Dongyuemiao member has high brittle mineral content and low clay mineral content, and higher organic matter content at the lower part than that at the upper part.Geochemical index, such as paleoclimate, paleoproductivity, paleoredox, paleosalinity has obvious vertical differences in the Dongyuemiao member.The lower part of Dongyuemiao member shows dry paleoclimate, dysoxic water column, saline water and high paleoproductivity, but the upper part of Dongyuemiao member shows warm and humid paleoclimate, low salination water and low paleoproductivity.It is concluded that the lower part of Dongyuemiao member has been more favourable for organic matter enrichment.
Keywords：western Hubei-eastern Chongqing areamudstoneDongyuemiao membergeochemistrysedimentary environmentpetroleum geology.
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：12( 1235-1246 )