延安地区上三叠统长6期储层成岩作用及孔隙演化

Diagenesis of the Upper Triassic Chang 6 formation in Yan'an area and pore evolution

延安地区为湖泊三角洲前缘沉积,沉积作用和成岩作用控制着储层孔隙。储层中原生粒间孔和次生孔隙所占比例相当,其中,绿泥石膜对研究区储层孔隙的保存起重要作用,为后期次生孔隙的生成提供了先决条件。同时,浊沸石大量溶解是研究区储层的一大特点,而绿泥石膜和浊沸石溶孔的匹配关系有利于优质储层的形成,可构成研究区最好的储层类型,对进一步寻找浊沸石分布带有重要指导意义。

Yan'an area belongs to lacustrine delta front sedimentation and the reservoir pores are controlled by sedimentation and diagenesis with almost equal amounts of primary intergranular pores and secondary pores.The chlorite membrane has played an important role in protecting the reservoir pores in the study area and provided the prerequisites for the development of secondary pores at a later stage.The reservoir in the study area is also characterized by dissolution of a large amount of laumontite.The matching of chlorite membrane with laumontite dissolved pores is helpful to the formation of high-quality reservoirs and also is helpful to forming the best reservoir type in the research area,which has important meanings for the further exploration in laumontite distributed areas.