中国石油大学学报（自然科学版）2024，Vol.48Issue(4)：131-140,10.DOI:10.3969/j.issn.1673-5005.2024.04.014
孔喉结构对超深层碳酸盐岩气藏多类型储层渗流能力的影响
Effect of pore throat structure on flow capacity of multi-type ultra-deep carbonate gas reservoirs
摘要
Abstract
The pore-throat structure of ultra-deep carbonate gas reservoirs is highly heterogeneous,and its flow mechanism is complex.In this study,rock samples of the Qixia Formation in the Shuangyushi block in the Northwest Sichuan Basin were selected,and various methods were used for core analysis and flow experiments,including multi-scale CT,nuclear magnetic resonance,stress-sensitivity,elastic energy testing under reservoir conditions,single-phase flow and gas-water two-phase flow.The relationship between the characteristic parameters of pore-throat structure and the characteristic parameters of flow in the ultra-deep multi-type reservoir were systematically and quantitatively investigated,and the influences of fractures,macropores and matrix pores on single-phase and two-phase flow were analyzed.The results show that,different from medi-um-deep reservoirs,increase of the throat number is critical to the improvement of the flow capacity of the targeted ultra-deep reservoir.Development of fractures can greatly improve gas flow capacity of the rock samples by increasing the throat number of and improving the pore connectivity,which can reduce the threshold pressure gradient of water-bearing gas reservoirs,and shrink the gas-water two-phase copermeability interval.However,the stress sensitivity of the rock sample can be enhanced,and its flow capacity and elastic energy decrease rapidly under high pressure difference due to the characteristics of the frac-tures that can be easily deformed under pressure.Development of large pores or throats can improve the storage capacity of the reservoir,and their strong resistance to deformation is beneficial to reduce the stress sensitivity of rock samples,which can maintain high flow capacity and elastic energy of the rock samples under high pressure difference.In the actual produc-tion process,it should be considered to control the gas production rate for fracture-porous type and fracture-cavity type reser-voirs in the early stage of production in order to maintain long-term stable gas production rate,and to increase the production pressure difference or perform stimulation measures such as fracturing and acidification for cavity type and porous type reser-voirs in order to release reservoir productivity.关键词
超深层气藏/栖霞组/碳酸盐岩/渗流机制/缝洞结构/相关性分析Key words
ultra-deep gas reservoir/Qixia Formation/carbonate rock/flow mechanism/fracture-cavity structure/correla-tion analysis分类
能源科技引用本文复制引用
张钰祥,王忠楠,闫海军,位云生,曹正林,郭建林,杨胜来,邓惠,陈掌星,郑国强..孔喉结构对超深层碳酸盐岩气藏多类型储层渗流能力的影响[J].中国石油大学学报（自然科学版）,2024,48(4):131-140,10.基金项目
中国石油天然气有限公司科技项目(2023YQX10501,2023YQX10503ZK) （2023YQX10501,2023YQX10503ZK）
四川省自然科学基金项目(2023NSFSC0261) （2023NSFSC0261）
