四川盆地震旦系灯影组孔隙类型和充填特征——以天全县龙门剖面为例

Pore Type and Filling Characteristics of Sinian Dengying Formation in Sichuan Basin:A case study of the Longmen Profile in Tianquan

龙门剖面震旦系灯影组位于四川盆地西南部,总体上为一套障壁海岸相潮坪沉积.孔隙的发育主要受控于古岩溶作用,在纵向上具有旋回性,主要受控于海平面的升降变化和构造运动的抬升剥蚀.储层沥青在古风化面附近含量较高,且沥青的含量和产状的分布与储层储集性能有较好的正相关关系.通过对含沥青段和不含沥青段的对比研究发现,优质储层形成的条件是油气充注前孔隙保存较好,且有一定的构造高度.油气的充注可以使得储集空间得以保存,未被油气充注的储集空间在随后的地质历史中也被各种矿物充填.

The main sedimentary faces of Sinian Dengying Formation of Longmen section is tide deposits of barrier shoreline. The pore was mainly controlled by palaeokarst. Due to the sea level change and uplift erosion of the tectonic movement, it could find the eyclicity of the pores in the vertical sections. The bitumen has high levels near palaeokarst, where the content and the occurrences of the bitumen have the positive correlation with the quality of reservoir. Through the contrast between bitumen segment and non - bitttmen segment, there are the results that the formation of good reservoirs is the pores which were preserved well before hydrocarbon injection and the trap have a certain height. Hydrocarbon injection was better for preservation of the pores while the pores that were not injected by hydrocarbon were filled by various minerals in the subsequent geological history.