摘要
江汉盆地西南缘白垩系渔洋组储集层成岩作用主要包括机械压实、早期碳酸盐和硫酸盐胶结、石英和长石的次生加大、长石和早期碳酸盐的溶蚀、晚期碳酸盐的沉淀,成岩阶段处于晚成岩A期。压实作用和胶结作用使原生孔隙损失殆尽,溶蚀作用形成的次生孔隙是油气的主要储集空间。纵向上发育两个次生孔隙带,第一次生孔隙带埋深2 800 m~3 100 m,其形成主要与有机质成熟过程释放有机酸对碳酸盐胶结物和长石等的溶解有密切关系,第二次生孔隙带埋深3 300 m~3 600 m,其形成可能是由于硫酸盐热化学氧化还原反应的作用。次生孔隙的发育受到温度和流体性质的控制,断裂是酸性水从烃源岩注入储集岩的重要通道,长期继承性的构造高部位成为了溶蚀作用和次生孔隙发育的有利位置。
Major diagenesis of Yuyang Formation in the southwest Jianghan Basin included com- paction, cementation of earlier carbonates and sulphate, quartz and feldspar overgrowth, dissolution of feldspar and earlier carbonates, precipitation of later carbonates. The reservoir diagenetic stage has reached A substage of late diagenesis. The compaction and cementation lead to the disappearance of primary pores and the secondary pores caused by the dissolution become important location for oil and gas storage. There are 2 zones of secondary pores around depth ranging from 2 400 m-3 600 m. The first zone of secondary pores (2 800 m-3 100 m) was controlled by dissolution of feldspar and earlier carbonates caused by organic acids. The second zone of secondary pores (3 300 m-3 600 m) may be related to thermo-chemical sulfate reduction. The development of secondary pores is controlled by temperature and propety of formation water. Fault was a main migration channel for acid water from source rocks to reservoirs and the structural high position was favourable location for dissolution and the distribution of secondary pores .
出处
《矿物岩石》
CAS
CSCD
北大核心
2007年第2期78-85,共8页
Mineralogy and Petrology
基金
中国石油化工股份有限公司科技部科研项目(编号:P01047)