鄂尔多斯盆地西南部宁县—庆阳地区长6期物源状况分析  

Provenance Analysis of the Chang 6 Formation in the Ningxian-Qingyang Region,Southwestern Ordos Basin

作　　者：罗媛[1] 赵俊兴[1] 吕强[2] 李凤杰[1] 

机构地区：[1]成都理工大学沉积地质研究院,四川成都610059 [2]中国石油长庆油田分公司,陕西西安710021

出　　处：《天然气地球科学》2009年第6期907-915,共9页Natural Gas Geoscience

基　　金：国家自然科学青年基金项目"鄂尔多斯盆地晚三叠世延长期几个关键性事件沉积及其与油气聚集关系研究"(编号:40602012);四川省教育厅自然科学青年基金联合资助.

摘　　要：为查明鄂尔多斯盆地西南部宁县—庆阳地区长6期物源状况,揭示该地区沉积体系展布格局,在大量分析化验基础上,利用Dickinson三角投点图判别了物源区的构造背景,通过碎屑组分分布、重矿物组合分区、岩屑分布及地震剖面等多种角度对庆阳地区延长组长6油层组沉积时期的物源及源区母岩性质等进行了系统分析。结果表明,长6期物源区构造背景为构造较复杂的造山带,在宁县—庆阳地区存在了西部、西南和南部3个不同物源方向,东北部为混源区。古物源与沉积砂体展布空间配置关系良好,并决定了该地区长6时期的沉积体系分布格局。对该地区古物源进行分析将有助于下一步油气勘探的部署。In order to ascertain the provenance of the Chang-6 Formation in the Ningxian-Qingyang region,in southwestern Ordos Basin,and to reveal the distribution of sedimentary system,this article,on the basis of analyses and assays,used the Dikinson triangular plot of sandstone clastic composition to determine the tectonic setting. The types of the parent rocks and the directions of sediment supply were discussed from clastic distribution,heavy mineral assemblages,sandstone distribution,etc. The results show that the tectonic setting of Chang-6 Formation is a complex orogenic belt and the principal sources are from west,southwest and south,and the northeast is the mixed provenance area in the Ningxian-Qingyang region. Provenance has a favorable spatial combination with depositional system,which determines the depositional system pattern of the Chang 6 Formation.

关 键 词：鄂尔多斯盆地 宁县-庆阳地区 延长组 长6期 物源分析 

分 类 号：TE121.3[石油与天然气工程—油气勘探]