东海盆地西湖凹陷G构造储层特征研究

为了进一步研究西湖凹陷G构造的储层特征,运用薄片分析、扫描电镜、X衍射分析等多种方法,对该构造储层岩石学特征、孔隙类型、孔隙结构特征及物性特征进行分析研究。结果表明:储层岩石类型主要是长石岩屑砂岩,其次是岩屑长石砂岩;粒间溶孔、粒内溶孔、铸模孔以及原生粒间孔是主要储层孔隙类型,孔隙结构以小孔隙、细喉道、分选中等的特征为主;花港组储层主要为中-低孔隙度、中-低渗透率储层,平湖组储层为特低孔隙度、特低渗透率储层。最后根据上述研究结果,综合分析得出沉积条件、成岩作用和异常高压是影响研究区物性的主要因素。

Study on Reservoir Characteristics of G Structure in Xihu Depression,East China Sea Basin

In order to study further on the reservoir characteristics of G structure in Xihu Depression,many methods have been used,such as slice analysis,scanning electron microscopy,x-ray diffraction and so on.The study is conducted mainly on analysis of the petrological characteristics,pore types,pore structure and physical properties.The study results indicated that the rock types are dominated by feldspathic lithic sandstones,and secondly are lithic arkose.Dissolved pores between grains,dissolved pores in grains,moldic pores and primary intergranular pores are main pore types.Pore structure types are small pore,and narrow throat,being middle sorted.Huagang Fm.reservoir is middle to low porosity and middle to low permeability,Pinghu Fm.reservoir is extremely low porosity and permeability.Finally,based on the above study results,it is concluded that the sedimentation conditions,diagenesis,and abnormal overpressure are the main factors influencing the reservoir physical properties.