吐哈盆地水西沟群“近生近储”型致密砂岩气藏特征及其成藏机制  

Discussion on characteristics and accumulation mechanisms of 'proximal-generation and proximal-storage' type tight sandstone gas accumulations in Shuixigou Group,Turpan-Hami Basin

作　　者：杨玉平 钟建华[1,2] 孙玉凯[3] 王劲松[3] 范莉红 倪良田 赵勇生 

机构地区：[1]中国石油大学地球科学与技术学院,山东青岛266580 [2]中国科学院广州地球化学研究所,广东广州510640 [3]中石油吐哈油田分公司勘探开发研究院,新疆哈密839009

出　　处：《中国石油大学学报（自然科学版）》2014年第4期34-41,共8页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金石油化工重点基金项目(U1262203);国家油气重大专项(2011ZX05009-002)

摘　　要：通过对多种地化指标的分析、对气藏与煤层关系的统计对比以及储层物性的测定,在野外露头观测、精细岩心观察和区域沉积剖面对比的基础上,总结吐哈盆地水西沟群的沉积模式,并结合气藏剖面实例对水西沟群致密砂岩气藏进行研究。结果表明:研究区致密气与其煤系源岩密切相关;成藏的有利因素主要来自于砂岩与煤层的大面积直接接触,以及决口扇体及构造裂缝这种'烟囱'状通道对源储的有效连通,其在本质上是一种源、储皆在水西沟群内的煤系源岩和致密砂岩储层间产生、运移和聚集的'近生近储'型气藏。Based on field outcrops and fine core observations,as well as contrasting regional sedimentary profiles,a sedimentary model was summarized in the Shuixigou Group,Turpan-Hami Basin by combining a series of analyses of a variety of geochemical indexes,the statistics and contrast of the relationship between the gas layer and the coal strata,and the survey of reservoir physical properties. With examples of gas accumulation profiles,the tight sandstone gas accumulations in the Shuixigou Group were studied. The results show that there are genetic relationships between the Jurassic gas and the coal series source rock in the Shuixigou Group. The favorable accumulation factors of the Jurassic tight sandstone strata in Turpan-Hami Basin mainly include the direct contact of the sandstones with the coal layers in large areas,as well as so-called＂chimneylike＂channels as crevasse splay bodies and structural fractures serving as an effective connecting medium between sources and reservoirs. Tight sandstone gas accumulations of Shuixigou Group in Turpan-Hami Basin is a ＂ proximal-generation and proximal-storage＂ type in nature whose generation,migration and accumulation are all confined to the Shuixigou Group itself.

关 键 词：致密砂岩 煤系烃源岩 决口扇 近生近储 成藏机制 

分 类 号：TE122.1[石油与天然气工程—油气勘探]