古地理学报2018，Vol.20Issue(1)：147-162,16.DOI:10.7605/gdlxb.2018.01.010
准噶尔盆地玛湖凹陷下二叠统风城组碱湖岩石特征与成因
Lithological characteristics and origin of alkaline lacustrine of the Lower Permian Fengcheng Formation in Mahu Sag, Junggar Basin
摘要
Abstract
The Lower Permian Fengcheng Formation,as favourable source rock in the Junggar Basin,has been the target for petroleum exploration.Due to its deep burial depth,complicated lithology and few global analogs,the evaluation of the petroleum potential of Fengcheng Formation is still at its rudimentary stage.This study discusses the characteristics of alkaline minerals,geological background,origin of alkaline lakes and its forming processes through methods including core description,thin section observa-tion,SEM,X-ray diffraction analysis,TOC content measurements,inclusion temperature test,geochemical analysis,etc.the results suggest:(1) the Fengcheng Formation can be categorized into five rock types,among which,alkaline rock is the most distinguished lithofacies type of alkaline lakes and reedmergnerite is generally related to volcanic eruption or hydrothermal activities;(2) five rock associations are recognized in the Fengcheng Formation.From near-source to lake center,they are type Ⅴ of alluvial-fluvial facies,type Ⅲ and Ⅳ of shallow shoreface to lacustrine facies,respectively;type Ⅰ and Ⅱ of deep-semideep lacustrine facies,respectively.Type Ⅰ and Ⅲ are typical alkaline rock associations with favourable source rock potential;(3) the formation of alkaline lake is primarily controlled by volcanic activities and climate,where the former supply the Na-rich fluids,and the latter salinized the freshwater lake and facilitate the final formation of alkaline lake.关键词
准噶尔盆地/下二叠统风城组/碱湖/岩石类型/岩石组合/成因分析Key words
Junggar Basin/Lower Permian Fengcheng Formation/alkaline lacustrine/rock types/lithology association/genetic analysis分类
天文与地球科学引用本文复制引用
汪梦诗,张志杰,周川闽,袁选俊,林敏捷,刘银河,成大伟..准噶尔盆地玛湖凹陷下二叠统风城组碱湖岩石特征与成因[J].古地理学报,2018,20(1):147-162,16.基金项目
国家油气重大专项(编号:2017ZX05001)和中国石油科技项目(编号:2016B-0302-01)联合资助.[Co-funded by the Major National Oil and Gas Special Projects(No.2017ZX05001) and CNPC Science and Technology Project(No.2016B-0302-01)] （编号:2017ZX05001）
