苏北盆地上白垩统泰州组砂岩成岩序列和储集层质量主控因素分析  

Sandstone diagenetic succession and major factors controlling reservoir quality of the Taizhou Formation of Upper Cretaceous in Subei Basin

作　　者：朱筱敏[1] 刘长利[1] 张亚雄[1] 刘为付[1] 陈莉琼[2] 王文军[2] 杨立干[2] 

机构地区：[1]中国石油大学北京,北京102249 [2]中国石化江苏油田地质研究院,江苏扬州225200

出　　处：《古地理学报》2008年第5期439-446,共8页Journal of Palaeogeography：Chinese Edition

摘　　要：基于53口井310余块储集层砂岩样品的分析研究,指出上白垩统泰州组储集层存在着压实（压溶）、胶结和溶蚀等成岩作用类型,但在不同位置成岩作用的表现有所不同。海安凹陷以胶结和溶蚀作用为主,压实与压溶作用不太明显;高邮凹陷的压实程度较海安凹陷强烈。压实作用使得高邮凹陷泰州组在2400-2800,m储集层孔隙度为10%左右,而海安凹陷为10%-20%。海安凹陷和高邮凹陷泰州组储集层目前处于中成岩阶段A期。储集层质量主要受原始沉积环境和成岩作用的综合影响。压实作用和胶结作用均可降低孔隙度,但当碳酸盐胶结物含量小于15%时,胶结作用对储集层质量影响较小。碳酸盐胶结物和长石颗粒溶蚀形成了大量的粒间溶孔。海安凹陷有利储集层主要分布在西北部和东部的三角洲前缘砂体和滑塌浊积扇砂体中,高邮凹陷有利储集层主要分布在南部扇三角洲前缘砂体中。Based on the analyses of over 310 sandstone samples from 53 wells, the reservoirs in the Taizhou Formation of Upper Cretaceous in the Subei Basin experienced compaction （pressolution） , cementation and dissolution processes, while the diagenesis showed different characteristics at different locations. The Haian Sag in the eastern part of the Subei Basin is dominated by cementation and dissolution, with non-obvious compaction and pressolution processes. The compaction extent in the Gaoyou Sag is stronger than that in the Haian Sag. The reservoir porosity of the Taizhou Formation in the Gaoyou Sag is about 10% at depth of 2 400 -2 800 m, while is about 10%-20% in the Haian Sag. Currently, the Taizhou Formation in the Haian Sag and Gaoyou Sag is at the stage A of mid-diagenetic stage. The reservoir quality is mainly controlled by comprehensive influence of the initial sedimentary environment and diagenesis. Compaction and cementation both can reduce the pore space, but when the carbonate cements content is lower than 15%, cementation has a smaller influence on the reservoir quality. The carbonate cements and feldspar grains created a great deal of intergranular dissolution pores. The favorable reservoir in the Haian Sag is mainly distributed in the northwestern and eastern delta front sandbodies and turbidite fan sandbodies, while in the Gaoyou Sag, it is distributed in the southern fan delta front sandbodies.

关 键 词：苏北盆地 海安凹陷 高邮凹陷 上白垩统 泰州组 成岩作用 成岩序列 储集层质量 

分 类 号：P130.21[天文地球—天体力学]