西藏羌塘盆地东湖地区上侏罗统索瓦组有机地球化学特征及意义  

Geochemical Characteristics and Geological Significance of the Upper Jurassic Suowa Formation in the Donghu Area of the Qiangtang Basin

作　　者：孙涛[1] 王成善[2] 李亚林[2] 魏玉帅[2] 何江林[3] 

机构地区：[1]中国海洋石油研究总院,北京100027 [2]中国地质大学(北京)地球科学与资源学院,北京100083 [3]成都地质矿产研究所,成都610000

出　　处：《矿物岩石地球化学通报》2013年第4期475-480,共6页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家油气专项(1212011221103);中央高校基本科研业务专项(2011PY0238)

摘　　要：羌塘盆地是青藏高原最大的海相盆地,索瓦组是盆地内重要的烃源岩。在盆地中部的东湖地区的索瓦组保存条件好,前人较少在该地区开展石油地质研究。通过对羌塘盆地东湖地区上侏罗统索瓦组进行系统采样、有机岩石学及有机地球化学分析研究,可知索瓦组灰岩沉积于碳酸盐台地环境,有机碳含量为0.10%～0.42%,有机质类型为Ⅱ型,母质主要来源于藻类及少量高等植物的输入,有机质镜质体反射率(Ro)在1.5%左右。生物标志化合物组成分布特征显示,索瓦组沉积于分层的水体且底部水体盐度较高。The Qiangtang basin is the largest marine basin in the Tibet Plateau.Carbonate rocks of the Upper Jurassic Suowa Formation are among the most important hydrocarbon source rocks.Although having good conditions for petroleum preservation,the Suowa Formation of the Donghu area received limited petroleum studies.The upper Jurassic limestones from the Donghu area in the Qiangtang basin,northern Tibet,China,were systematically collected and analyzed by organic petrology and organic geochemistry methods.The results indicated that the samples from the Suowa formation were deposited in carbonate platform environment and that their TOC contents rang from 0.10% to 0.42%.The organic matter composes algae organic matter and a few terrigenous organic inputs;the kerogen can be classified as TypeⅡ with moderate oil generation potential.The vitrinite reflectance data vary between 1.5%~1.6%.Biomarker composition suggests a stratification water column with saline bottom waters.

关 键 词：羌塘盆地 索瓦组 生物标志化合物 镜质体反射率 

分 类 号：P618.13[天文地球—矿床学]