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地震剖面分析表明,酒泉盆地石北地区发育有一系列的北倾逆断层及相关褶皱,主要形成于晚第三纪?第四纪时期。其活动强度具有自西而东逐渐减弱的规律,向东消失于石北Ⅰ号和石北Ⅱ号两条早白垩世正断层的附近,表明与阿尔金断层的活动密切相关。而下第三系底部与下白垩统顶部之间的角度不整合以及剥蚀厚度北厚南薄的特征表明,部分北倾逆断层早在晚白垩世时期就已经开始了强烈地活动,形成了一系列的断层相关褶皱,并造成石北及其北面的宽台山?黑山地区形成了晚白垩世隆起的雏形。这些断层相关褶皱是良好的油气圈闭,对石北地区的油气分布具有重要的控制作用。
Seismic profile analysis shows that there are a series of North-dip thrust faults and related folds developed in the Shibei area of Jiuquan Basin, which mainly formed in the late Tertiary-Quaternary period. Its activity intensity gradually decreases from west to east and disappears to the east of two Early Cretaceous normal faults in Shibei Ⅰ and Shibei Ⅱ, indicating that it is closely related to the activity of the Altyn Tagh fault. The unconformity of the angle between the bottom of the Lower Tertiary and the top of the Lower Cretaceous and the characteristics of denudation thickness of the north and south thin sections indicate that some of the North-dip thrust faults have already started intense activity as early as the Late Cretaceous and formed a Series of fault-related folds, resulting in the formation of late Cretaceous uplift prototypes in the northern part of Shibei Mountain and its northern part. These fault-related folds are good hydrocarbon traps and have an important control over the oil and gas distribution in the Shibei area.