西湖凹陷黄岩构造带花港组砂岩储层成岩作用研究

根据岩石薄片、铸体薄片、扫描电镜、X-衍射等多种分析测试资料，对西湖凹陷黄岩构造带古近系花港组砂岩储层成岩作用及其对储层物性的影响进行了详细研究。岩石薄片资料分析显示黄岩构造带花港组砂岩类型主要为长石岩屑质石英砂岩，成分成熟度和结构成熟度均为中等。在薄片观察的基础上，结合分析测试资料，认为研究区成岩作用类型主要有压实作用、胶结作用、交代作用和溶蚀作用，储层成岩演化阶段整体上处于中成岩A期；压实作用和胶结作用是该区主要的破坏性成岩作用，其中碳酸盐胶结物不仅占据着原生孔隙，且充填了次生孔隙，溶蚀作用则属于建设性成岩作用，产生的大量次生孔隙有效改善了储层物性，并在3500m左右形成了次生孔隙发育带。

Diagenesis of sandstone of Huagang Formation in Huangyan tectonic belt, Xihu sag

Based on the analysis of general thin-section, casting lamella, scanning electron microscope, X-ray diffraction and other analysis methods, the diagenesis of Paleogene Huagang Formation in Huangyan tectonic belt of Xihu Sag is studied in detail. The result shows that feldspathic-lithic quartz sandstone is the main sandstone type with medium maturity of texture and component. The vitrinite reflectance and paleogeotemperature reveal that diagenetic stage of reservior is at middle diagenetic A stage. Compaction, cementation, metasomatism and dissolution are recongnized, which are main types of diagenesis in sandstone reservoir. Compaction and cementation are typical destructive diagenesis, which destroy most primary pores and a large volume of secondary pores are filled by carbonate cements, whereas the dissolution developed in study area produces a lot of secondary pore, which forms the secondary pore zone at a depth of 3500 meters and improves the reservoir physical properties effectively.