伊宁凹陷二叠纪古构造演化与油气关系

伊宁凹陷构造变形强烈，构造演化认识不清。利用地震、钻井资料恢复了伊宁凹陷二叠纪—古近纪古构造面貌，以及期间所遭受的构造剥蚀情况，在此基础上对二叠系生油岩可能的油气运聚进行预测后指出，伊宁凹陷在三叠纪由断陷转为凹陷。二叠纪—古近纪伊宁凹陷整体上北低南高、西低东高；二叠纪伊宁凹陷北部为深陷带，南部、东部为斜坡区，且南坡较东坡陡；三叠纪伊宁凹陷构造变得低缓，凹陷中央次凸带发育北西西向延伸的小凸起；侏罗纪伊宁凹陷沉降中心向北东方向转移，南坡变缓，东坡变陡。凹陷中部的宁4井附近的断凸、伊2井西的断鼻、英塔木南的断鼻均为为铁木里克组油气的有利聚集区。

Paleostructural Evolution and Relationship with Hydrocarbon of Permian in Yining Sag

The tectonic deformation in Yining sag is so strong that leads to unclear understandings of the tectonic evolution up to now. This paper restored the paleotectonic features of Permian-Paleogene in Yining sag by means of the seismic and drilling data, including the denudation thickness, by which predicted the probable hydrocarbon migration and accumulation for the Permian source rocks. The result shows that Yining sag was converted from fault depression into sag in Triassic; the sag’s shape appears low in north and west and high in south and east in general from Permian to Paleogene; in the Permian, the northern part of the sag was a deep rifted belt, the south and east parts were in slope area that looks like steeper in the south than in the east; in the Triassic, the sag structure became lower, the sub?swell zone in the central sag occurred some small swells extending along NWW; in the Jurassic, the subduction center of the sag transferred toward NW, appearing flat in the south slope and steep in the east one. It is concluded that the fault swell near Well Ning?4 and fault nose at the west of Well Yi?2 in center of the sag and fault nose in the south of Yingtamu could be the favorable hydrocarbon accumulation areas of Tiemulike formation in Yining sag