大湾地区飞仙关组成岩作用对孔隙演化的影响  

Influence of Diagenesis on Pore Evolution in Dawan Area

作　　者：陈岑[1] 毕建霞[1] 成群 张纪喜 陈建 

机构地区：[1]中原油田勘探开发研究院,河南郑州450000 [2]大庆油田采油三厂,黑龙江大庆163000

出　　处：《中国西部科技》2015年第6期35-38,共4页Science and Technology of West China

基　　金：国家重大科技专项"高含硫气藏安全高效开发技术"(编号:2011ZX05017-001)

摘　　要：运用铸体薄片、扫描电镜、岩心化验等微观分析方法对大湾地区飞仙关组储层的成岩作用和孔隙演化特征进行研究。结果表明飞仙关组碳酸盐岩储层主要成岩作用为:白云化、压实压溶、方解石胶结、多期溶蚀、充填、重结晶作用等。根据成岩特征综合分析,储集岩主要形成于波浪沙作用比较强的台地边缘鲕粒滩沉积相带中,以鲕粒细晶白云岩、砂屑细晶白云岩为主,颗粒直径大,白云岩化程度高,分选为好-中等,但成岩作用强烈。在海底-同生暴露阶段,压实及方解石胶结作用使储层孔隙度急剧下降。该过程中,虽有混合水白云化和大气淡水溶蚀作用形成次生孔隙,但原生孔隙大量减少;浅埋藏阶段,在压实和胶结作用的影响下,孔隙度快速降低;后期溶蚀作用可以形成次生溶孔,对岩石孔隙度的增加具有相当大的贡献。Diagenesis and pore evolution characteristics of Feixianguan Formation in Dawan gas reservoir were fully studied based on the microscopic-analysis on casting thin sections, scanning electricity mirror, and core analyzing materials. The results showed that the mainly diagenesis types of carbonate reservoir in this area were dolomitization, compaction, cemented, filling, dissolution, recrystallization diagenesis, etc. In submarine and syngenetic stage, porosity dropped rapidly because of compaction and the calcite cementation. During this stage, the primary pores reduced greatly, despite mixed water dolomitization and meteoric fresh water dissolution formed secondary pores. In shallow burial stage, the pores drastically reduced under the condition of compaction and cementation. The later period of dissolution can form secondary dissolution pore, thus largely contributed to the increase of porosity.

关 键 词：大湾地区 飞仙关组 成岩作用 孔隙演化 

分 类 号：P618.130.2[天文地球—矿床学]