雅布赖盆地构造演化与油气聚集  

Structural evolution and hydrocarbon accumulation in Yabulai Basin

作　　者：吴晓智[1] 王桂君 郑民[1] 郑曼[1] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]新疆油田公司实验检测研究院,新疆克拉玛依834000

出　　处：《地质科学》2015年第1期74-87,共14页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家科技重大专项(编号:2011ZX05008)资助

摘　　要：雅布赖含油气盆地位于中国西部河西走廊地区北部,处于华北克拉通阿尔善地块中南部过渡带,属北祁连构造带,中生代为走滑拉分盆地,新生代为挤压冲断坳陷盆地。燕山早期,形成东西向雅布赖拉张断陷,主控断裂为北大山正断层,沉积中心位于盆地南部;燕山中期,碰撞造山作用致使盆地北部急剧抬升,北部中-下侏罗统地层遭受强烈剥蚀;燕山晚期,阿拉善地块及其北部地区处于伸展构造环境,雅布赖山前产生东西向正断层,急剧活动,快速沉降,形成了北东向展布的新的拉张断陷盆地。喜马拉雅期,在挤压走滑作用下,雅布赖盆地南部形成北西向南倾逆冲的推覆构造,致使北大山正断层发生错断瓦解,最终形成"东隆西坳,南断北超"的挤压坳陷构造格局。雅布赖盆地主体沉积凹陷具有较强分割性,沉降凹陷分布于南部,最大沉积岩厚度为5 400 m;凹陷内侏罗系最为发育,中侏罗统新河组、青土井组暗色泥岩、煤岩为烃源岩,砂岩为储集层,新河组泥岩互层作盖层,构成盆地内最主要的含油气组合。由于雅布赖盆地特定的早期深埋,晚期抬升破坏构造格局,造就侏罗系砂岩储层早期强烈压实致密,侏罗系煤系烃源岩成熟较晚,构造发育期与烃源岩排烃期不匹配,生成油气主要表现为近源成藏与层内滞留,形成源内自生自储,致密油应是主要勘探对象。Yabulai oil-bearing basin which located in the western part of Hexi Zoulang lies at the transitional zone between North China Craton and Alashan block and it belongs to North Qilian tectonic belt.It experienced basin evolution of Mesozoic strike-slip pull-apart to Cenozoic compression thrusts.In the Early Yanshannian,EW trending extensional faults developed,and the depocenter lies in the southern part of basin mainly controlled by Beidashan normal fault.During the Middle Yanshannian,collision orogeny resulted in a sharp uplift of the northern basin,the Lower Jurassic strata eroded intensely.Alashan block and its northern territory were in extensional tectonic environment during the Late Yanshannian,EW trending extensional faults were generated in front of Yabulai Mountain.Rapid subsidence resulted in new NE trending extensional rift basin.During the Himalayan,affected by the strike-slip and extrusion,NW trending and south-dipping nappe and thrust faults were generated in the southern Yabulai Basin.Which make the Beidashan normal faults occur dislocation collapse,eventually forming the tectonic framework showing ＂fault in the south,overlap in the north,uplift in the east and depression in the west＂.The sedimentary sag of Yabulai Basin have,subsidence sag located in the south,the maximum thickness of sedimentary rocks is 5400 m,the most developed strata is Jurassic.Dark mudstone and coal from the Xinhe Formation and Qinhejing Formation of Jurassic are source rock and the sandstones are reservoir.The seal is interbeded mudstone from the Xinhe Formation.They constitute the main hydrocarbon combination.Yabulai Basin was deep buried in the early,but the late uplift destroyed the tectonic framework,resulted in the Jurassic sandstone reservoir experienced strongly compaction in the early and the Jurassic coal source rock became mature late.Structure development time is mismatched with the time of hydrocarbon explosion.Generated hydrocarbon are accumulated near the source rock or stranded in the situ.So that the sourc

关 键 词：构造层划分 构造特征 构造演化 油气聚集 成藏模式 雅布赖盆地 

分 类 号：P542[天文地球—构造地质学] TE121[天文地球—地质学]