准噶尔盆地南缘层序地层特征与有利含气区带预测

准噶尔盆地南缘近期的油气勘探表明其具有巨大的资源潜力。文中运用以基准面旋回为基础的层序地层理论,将该区中、新生代地层划分为5个长期地层旋回:LSC1、LSC2、LSC3、LSC4、LSC5,并总结了旋回的发育特征。在旋回格架内分析了其气储集层、盖层的分布及储盖组合的发育特征,指出本区研究层段主要发育LSC5、LSC4、LSC2和LSC14套储盖组合,其中LSC4、LSC1为最有利的含气储盖组合。综合生油、构造等其它成藏条件,作者指出了本区两个有利的气聚集带:南缘山前气聚集带(侏罗系为主要目的层)和西湖-玛纳斯-呼图壁有利气聚集带(下第三系为主要目的层)。 

CHARACTERISTICS OF SEQUENCE STRATIGRAPHY AND PREDICTION OF FAVORABLE GAS ZONES FOR THE SOUTH EDGE OF THE JUNGGAR BASIN

The recent exploration of oil and gas in the south edge of the Junggar Basin shows that there is huge resource potential in this area. In this paper, the sequence stratigraphic theory based on base-level cycles is used to divide the Mesozoic and the Cenozoic strata of this area into five secular stratigraphic cycles, including LSC1.LSC2, LSC3, LSC4 and LSC5. The developing characters of these cycles are summarized. In the framework of cycles, the dist ribution of reservoirs and cap rocks and the developing characters of their assemblages are analysed. It is pointed out that the study st rata of this area mainly develop LSC5, LSC4, LSC2 and LSC1 four assemblages. Among them, LSC4 and LSC1 are the most favorable gas assemblages of reservoirs and cap rocks.Combined with oil-generating, tectonic and other pool-forming conditions, two favorable gas-accumulation belts in this area are suggested, i. e. the Shanqian gas-accumulation belt in the south edge whose major target stratum is the Jurassic and the Xihu-Manasi-Hutubi favorable gas-accumulation belt whose major target stratum is the Lower Tertiary.