摘要
应用大量压力、物性、试油测试数据,分析渤海湾盆地辽河坳陷西部凹陷南段古近系低压和异常低压对储集层成岩作用和物性的影响。当地层压力为低压或异常低压时,孔隙流体压力较小,上覆静岩压力主要由砂岩骨架颗粒承担,有时甚至出现"过压实"现象,导致储集层致密,促进机械压实作用;地层剩余压力与碳酸盐胶结物含量之间呈负相关关系,具有低压或异常低压的致密砂岩碳酸盐胶结物含量比处于静水压力—弱超压条件下的砂岩更高;低压区和异常低压区的砂体孔隙流体中含有较多的Si4+,有利于硅质胶结作用的进行;处于低压或异常低压背景下的储集层,当溶蚀作用发生时,其原始物性已经相对较差,不利于溶蚀流体的注入和溶解物质的排出,溶蚀作用相对较弱。因此,发育低压或异常低压的储集层物性较差。
The effect of low pressure and abnormally low pressure on reservoir diagenesis and physical property of the Paleocene in southern part of Western Sag of Liaohe Depression, Bohai Bay Basin have been analyzed using large amounts of pressure, physical property and formation testing data. When formation pressure is low or abnormally low, the pore fluid has lower pressure, the overburden litho-static pressure is largely born by the sandstone framework, sometimes over compaction occurs, leading to densification of reservoir and stronger mechanical compaction; residual formation pressure has a negative correlation with carbonate cement content, low pressure or abnormally low pressure tight sandstone formations have higher carbonate cement content than sandstone formations with hydrostatic pressure or weak overpressure; pore fluid in sandstones with low pressure or abnormally low pressure has higher Si^4＋, conducive to the siliceous cementation; when dissolution happens, reservoirs with low pressure or abnormally low pressure, poor in original physical properties, are not favorable for the injection of dissolution fluid and the expulsion of dissolution products, so they have weaker dissolution. In summary, reservoirs with low pressure or abnormally low pressure have poorer physical properties.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2016年第4期669-674,共6页
Petroleum Exploration and Development
基金
国家自然科学基金项目(U1262106
41572135)
关键词
异常低压
成岩作用
储集层物性
致密砂岩
西部凹陷
辽河坳陷
abnormally low pressure
diagenesis
reservoir physical property
tight sandstone
Western Sag
Liaohe Depression
