高桥地区盒8段储层特征及控制因素

摘要

By analyzing thin sections, scanning electronic microscope and physical properties, the petrology characteristics, pore types and reservoir properties of He 8 member in Gaoqiao area were studied. The result shows that the rocks of the reservoir of He 8 member which deposited in braided delta front are mainly composed of quartz sandstone and lithic quartz sandstone with high compositional maturity and medium textural maturity. The reservoir developed secondary dissolved pores primarily, followed by kaolinite inter-crystalline pores and primary intergranular pores, and a little microerack. The average porosity is 6.37% and the average permeability is 0.81 mD, and it belongs to typical low porosity and low permeability reservoir. The main factors influencing the reservoir properties were analyzed. The reservoir properties are controlled by provenance and sedimentary facie zone in plane, and controlled by compaction and cementation in the vertical direction, whereas the secondary pores produced by dissolution improve the reservoir properties.%综合运用岩石薄片、铸体薄片、扫描电镜及物性分析等资料,对高桥地区盒8段气层组的岩石学特征、孔隙类型及储层物性进行了深入研究。结果表明,以辫状河三角洲前缘为主的盒8段储层主要为石英砂岩及岩屑石英砂岩,具有成分成熟度高、结构成熟度中等的特点。储集空间以次生溶孔为主,高岭石晶间孔及原生粒间孔次之,见少量微裂缝。孔隙度平均为6.37%,渗透率平均为0.81mD,为典型的低孔、低渗储层。在储层特征研究的基础上,分析了影响储层物性的主要因素,平面上主要受物源、沉积相带的控制,垂向上主要受压实和胶结作用控制,溶蚀作用产生的次生孔隙使储层物性得到改善。