鄂尔多斯盆地基底结构特征及其对古生界天然气的控制

STRUCTURAL FEATURE OF BASEMENT IN THE OR DOS BASIN AND ITS CONTROL TO PALEOZOIC GAS

鄂尔多斯盆地位于华北克拉通西部，是我国大型含油气盆地之一。基底结构复杂，具有显著的不均匀性；基底断裂数量多、规模大；基底顶面表现为两个大型隆起，北部为伊盟隆起，中南部为中央古隆起；盆地基底结构对上覆沉积盖层岩性、岩相具明显控制作用，从而间接影响到油气的生成、运移与聚集。伊盟隆起的南侧斜坡及中央古隆起四周斜坡地带，是寻找古生界天然气的有利场所；盆地中南部几条ＮＥ向大型韧性剪切带，可能对油气分布产生重要影响，在油气勘探中也应给予重视。

The Ordos basin,one of the large hydrocarbon bearing basins,is located in the west part of North China.There are many big basement faults making up a complex pattern with two uplifts lying on the top of the basement.The complex and heterogeneous basement structure controls obviously the overlying sedimentary lithology and its formation,and influence indirectly the generation,migration and accumulation of hydrocarbon.The south slope of the northern Yimeng Uplift and the slope region around the central uplift are favorable for seeking Paleozoic natural gas.Several large northeastern ductile shearing belts may influence the hydrocarbon distribution greatly and much attention should be devoted to the oil and gas exploration.