准噶尔盆地油气幕式成藏规律探讨

Episodic reservoir-formation rules in the Jungar Basin, Northwest China

准噶尔盆地油气田的形成经历了多幕成藏、多期改造及后期调整的过程。根据主要构造幕、主要生油期、主要输导体系以及主要油气田成藏期,初步划分出5幕主要油气成藏期,即印支Ⅱ幕(T末)、燕山Ⅱ幕(J末)、燕山Ⅳ幕(K末)、喜马拉雅Ⅱ幕(E末)、喜马拉雅Ⅲ幕(N末)。在此基础上分析,认为东道海子北凹陷北斜坡、玛湖凹陷东南部、陆梁油田北部以及昌吉凹陷东北斜坡等将是寻找大中型油气田的有利地区,主要目的层是侏罗系-白垩系,以隐蔽油气藏为主。

The oil and gas fields in the Jungar Basin are generated in multi-episodes reservoir-formation, reconstruction and late adjustment. Five episodes, asⅡ Episode of Indo-Chinese epoch ( Late Triassic), Ⅱ Episode of Yan Shan ( Late Jurassic), Ⅳ Episode of Yan-shan ( Late Cretaceous), Ⅱ Episode of Himalayan ( Late Eocene) and Ⅲ Episode of Himalayan ( Late Neogene), are divided preliminarily according to the main tectonic phase, oil generation period, transport system and reservoir-formation period of oil and gas fields. The zones, in the north slope of Dongdaohaizi Sag, the SE of Mahu Sag, the north of Luliang Oilfield and NE slope of Changji Sag, would be the favorable areas for exploration of large and middle scaled oil and gas fields. The main target is Jurassic-Cretaceous in which the main reservoirs are subtle ones.