川西丰谷地区须四段钙屑砂岩优质储层形成机理

Formation mechanism of high-quality reservoir of calcarenaceous sandstone in fourth member of Xujiahe Formation, Fenggu area, Western Sichuan Depression

罗文军 彭军 曾小英 刘焕 肖艳 唐勇 杨小陈

Luo Wenjun Peng Jun Zeng Xiaoying Liu Huan Xiao Yan Tang Yong Yang Xiaochen

西南石油大学资源与环境学院, 成都610500 2. 中国石化西南油气分公司勘探开发研究院, 成都610081 3. 中国石化西南油气分公司川西采气厂, 四川德阳618000 4. 中国石油华北油田分公司勘探开发研究院, 河北任丘062550

School of Resources and Enviroment, Southwest Petroleum Univesity, Chengdu, Sichuan 610500, China 2. Research Institute of Exploration and Development, SINOPEC Southwest Oilfield Company, Chengdu, Sichuan 610081, China 3. Chuanxi Gas Production Plant, SINOPEC Southwest Oilfield Company, Deyang, Sichuan 618000, China 4. Research Institute of Exploration and Development, PetroChina Huabei Oilfield Company, Renqiu, Hebei 062550, China

川西坳陷丰谷地区须家河组四段钙屑砂岩储层为典型的致密砂岩储层,以碳酸盐岩岩屑含量高(达到碎屑组分90%以上)、碳酸盐胶结发育、低孔低渗为特征,但在普遍致密的背景下部分层段发育优质储层(孔隙度达到12%以上)。通过对储层特征及成岩作用的深入分析,认为储层方解石的差异胶结作用是优质储层原生孔隙保存的关键,而后的破裂作用形成的裂缝沟通了储层与油气侵位的酸性流体,使储层得到大幅改善,后期油气的充注使储层孔隙得到良好的保护。

The calcarenaceous sandstone reservoir in the fourth member of the Xujiahe Formation in Fenggu area of the Western Sichuan Depression is a typical tight sandstone reservoir characterized by high content of carbonate debris(accounting for over 90% in total debris),well-developed carbonate cementation,low porosity and low permeability;however,under the background of general dense,favorable reservoirs also develop in some intervals with the porosity of over 12%.The analysis of reservoir feature and diagenesis has indicated that the differential cementation of reservoir calcite is the key for the preservation of primary pore in high-quality reservoir.Then disruption communicates reservoir and acid fluid of hydrocarbon emplacement,improving reservoir quality.The later hydrocarbon charge protects reservoir porosity.

中国石油科技创新基金(2010D-5006-0103)资助

https://doi.org/10.11781/sysydz201204412