库车坳陷乌什凹陷东部成藏作用初步研究

库车坳陷乌什凹陷依拉克气田由下白垩统舒善河组下部的3个凝析气藏组成,具有超高压、常温、孔隙型碎屑岩储集、超深层、层状边水、富特富凝析油含量特征,是乌什凹陷发现的第一个规模较大的气田.依拉克气田的成藏模式为烃灶远端侧向供气,通过断裂和裂隙与不整合面及输导层形成的网络充注,封存箱内渗流成藏.乌什凹陷东部烃源条件良好,盖层发育,中、新生界具有3层压力结构,深部存在区域性的异常压力流体封存箱,是富集形成规模大的油气藏的有利区域.远离烃灶成藏的特征证实该区属于库车超强充注油气系统的一部分,油气资源潜力巨大,有望发现更多的特富、富凝析气藏和油藏.图6表1参12

Gas pool forming process in Wushi Sag of Kuqa Depression, Tarim Basin

Yilake gas field are composed of 3 super-pressure, normal temperature, sandstone pore type reservoir, bedded style, edge water and rich-superrich gas condensate pools in the Lower Cretaceous Shushanhe Formation. It is the first giant gas field discovered in the Wushi Sag. The pool forming model of the Yilake gas field is characterized by feeding from far-forth of lateral hydrocarbon kitchen, charging from migration network formed by fault, fracture, unconformity interface and conveyance layer, and accumulating by vadose inside super-pressure fluid compartment. The east part of the Wushi Sag could develop giant oil and gas fields, it has excellent conditions of hydrocarbon source and seal, and a big area of abnormal pressure compartment formed by the three layers pressure structure. The feature of the pool forming from far-forth distance to the hydrocarbon kitchen has proved that the east part of the Wushi Sag belongs to a part of the Kuqa super-charge petroleum system. This prospect area has great petroleum resource potential, and might gain more rich-superrich gas condensate pools and oil pools.