摘要
金山气田沙河子组发育大型低渗透致密砂岩储层,其中相对高孔高渗带具有良好的勘探潜力,已有多口井获工业气流。通过普通薄片、铸体薄片、扫描电镜及黏土X衍射、物性资料等综合分析,对沙河子组储层特征及成岩作用进行研究,发现:1研究区砂岩以中粗粒岩屑长石砂岩为主,其次为长石砂岩;储集空间包括原生粒间孔、扩大粒间孔、长石粒内溶孔、岩屑粒内溶孔及溶蚀缝;2储层主要经历了压实和压溶作用、胶结和交代作用及溶蚀作用。储层物性明显受控于成岩作用,机械压实作用和胶结作用导致大量原生孔隙的减少,使储层物性变差;而溶蚀作用形成大量次生孔隙,甚至形成溶蚀缝,对储层物性具有极大的改善作用,控制了相对有利储层的发育。
In Jinshan gasfield, large-scale tight sandstone reservoirs with low permeability are developed in the Shahezi Formation. In particular, there is better exploration potential in some belts with relatively high porosity and permeability, and industrial gas flow was obtained from many wells. In this study, both reservoir characteristics and diagenesis of the Shahezi Formation were analyzed on the basis of thin-section and casting thin-section identification, SEM, X diffraction of clay, and some petrophysical data. Results show that(1) this reservoir is mainly composed of medium- to coarse-grained lithic arkose and secondly arkoses, and its space includes primary intergranular pore, enlarged intergranular pore,feldspathic intragranular dissolution pore, lithic intragranular dissolution pore, and dissolution fracture;(2) it dominantly experienced compaction and pressure solution, cementation and metasomatism,and dissolution in which, diagenesis affected petrophysical properties evidently, both compaction and cementation brought about a decrease of large amount of primary pores to further make these properties poorer, and dissolution formed plenty of secondary pores or even dissolution pores, which might advance these properties a lot and control the development of relatively favorable reservoirs.
出处
《天然气技术与经济》
2016年第5期5-9,81,共5页
Natural Gas Technology and Economy
关键词
储层特征
成岩作用
沙河子组
金山气田
reservoir characteristics
diagenesis
Shahezi Formation
Jinshan gasfield
