高桥区岩溶古地貌及岩溶储层发育特征研究

Gaoqiao area karst palaeogeomorphology and karst reservoir characteristics research

针对鄂尔多斯盆地靖边气田高桥区马五1+2储层致密、非均质性强、单井产能低的开发难点,根据岩心观察及铸体薄片、电镜扫描等分析化验资料,开展了该区古岩溶储层的风化残积物、岩溶角砾岩、孔洞缝发育特征及充填特征研究,采用"印模法、残余厚度法、地球物理、古地质图"等方法进行岩溶古地貌划分,将该区分为西部斜坡区、中部潜台区、东部沟槽区等三个二级地貌单元。认为高桥区主体处在低洼平缓的岩溶斜坡带,侵蚀沟槽不发育,孔缝内方解石充填程度高,导致该区储渗条件变差,平面上受不同强度溶蚀和充填作用的控制,主力储层为马五12、马五13小层,并具有明显的分区性,中部潜台区马五12较发育,东部沟槽区马五13发育程度高。

Jingbian gas field in Erdos Basin Gaoqiao district Mawul＋2 compact reservoir devel- opment is not difficult, strong heterogeneity, low productivity of a single well. According to the core observation,cast thin section, scanning electron microscope analysis of test data,the paper has described the weathered layer of ancient karst reservoir in the region of residues, karst breccia, cave development characteristics and filling characteristics, and used the im- pression method, residual thickness method,geophysics,ancient geological map method of karst landform classification,that Gaoqiao district is divided into three two geomorphm unit, such as the western slope area,the central area,the eastern trench potential area.That subject is in Gaoqiao area karst slope low-lying flat belt,erosion channel not development,aperture calcite filling degree is high, resulting in the reservoir permeability variation, the plane is controlled by different intensity of erosion and sedimentation, main reservoir is the Mawul2 and Mawu^3 layer,and has regionalization obviously,the Mawul2 layer is developed in the cen- tral area,however,the Mawul3 layer is developed highly in the the eastern trench potential area.