鄂尔多斯盆地伊盟隆起什股壕区带气藏类型

鄂尔多斯盆地伊盟隆起什股壕区带下二叠统山西组和下石盒子组发育岩性气藏和背斜气藏，为深入研究该区成藏规律和提高水平井的实施效果，对气藏的几何形态及其类型详细研究很有必要。利用钻井和地震资料，结合气、水层解释和测试成果，解剖了典型气藏的平面和剖面几何形态，分析了相关圈闭遮挡因素，将研究区气藏分为5种类型。纵向上，下石盒子组2段和3段主要发育岩性气藏，盒1段主要发育背斜气藏，山西组主要发育地层超覆气藏和构造-岩性复合气藏。平面上，区带西部斜坡区主要发育岩性气藏和地层超覆气藏，东部隆起区主要发育背斜气藏和构造-岩性复合气藏。研究区层间断层比较发育，除发育有小型断块气藏外，一些岩性气藏和背斜气藏被层间小断层切割，几何形态有所改变，利用三维地震资料可以精细地确认研究区气藏的几何形态。

Gas reservoir types in Shiguhao area of the Yimeng Uplift,Ordos Basin

Lithologic and anticlinal gas reservoirs were developed in the Lower Permian Shanxi Formation and Lower Shihezi Formation in Shiguhao area of Yimeng Uplift, Ordos Basin.In order to study the hydrocarbon accumulation rules and optimize emplacement of horizontal wells, it is essential to analyze the geometries and types of the gas reservoirs.Based on drilling and seismic data in combination with identification of gas and water layers and test results, this paper analyzed the geometries on plane and sectional views of typical gas reservoir and researched the mainly factors that influence the sealing of gas reservoirs.Five types of gas reservoirs are recognized in the study area.In vertical, lithologic gas reservoirs are mainly developed in the P₁x² and the P₁x³, anticlinal gas reservoirs are mainly developed in the P₁x¹, stratigraphic overlapping gas reservoirs and structural-lithologic gas reservoirs are the predominant types in the Shanxi Formation.On the plane, lithologic and stratigraphic overlapping gas reservoirs are mainly developed in the slope belt of western Shiguhao area; anticlinal and structural-lithologic gas reservoirs are mainly developed in uplift belt of eastern Shiguhao area.Meanwhile, interlayer faults are well developed in Shiguhao area.In addition to small scale fault block gas reservoirs, some lithologic and anticlinal gas reservoirs are cut by interlayer faults, changing their geometries.By using three-dimensional seismic data, the geometries of gas reservoirs can be depicted accurately.