龙门山前雷口坡组储层孔隙结构特征及开发评价意义探讨

Pore Structure Characteristics and Significance of Development Evaluation of Lei Kou Slope Formation Reservoir in Longmen Mountain Front

摘要: 基于储层特征，利用铸体薄片、CT扫描、岩心压汞及气水相渗实验等手段，分析不同类型储层的孔隙结构特征，研究未饱和汞饱和度、孔喉体积比、退汞饱和度、退汞效率等参数和两相渗流机理在储量评价中的应用，同时探索气水关系、气藏类型及采收率。研究表明储层孔喉比10:1，退汞饱和度14.1%~30.6%，退汞效率30%，原始含气饱和度72%，气藏高度115~158 米，相渗实验预测最终采收率40%。总体上具有孔喉比较大、微观连通性较差、退汞饱和度较小、储量动用难度较大等特点，同时气藏存在边水、开发中后期水侵较活跃的问题。

Abstract: Based on the reservoir characteristics, the paper uses the methods of cast thin section, scanning, CT core mercury injection and gas phase permeability experiment, analyzes pore structure characteristics of different types of reservoir, studies characteristic parameters of pore structure such as unsaturated mercury saturation, pore throat volume ratio, ejection saturation, mercury withdrawal efficiency etc. and application characteristics of two-phase flow in reserve evaluation, and explores the relationship between gas and water and recovery prediction. The research shows that the pore throat ratio is 10:1, the mercury removal degree is 14.1% - 30.6%, the mercury removal efficiency is 30%, the original gas saturation is 72%, the gas reservoir height is 115 - 158 meters, and the phase permeability test predicts the final recovery factor is 40%. In general, the reservoir has larger pore throat, poor micro connectivity, smaller mercury removal saturation and greater difficulty in the utilization of reserves. Meanwhile, gas reservoirs are characterized by edge water and water invasion in the middle and later stages of development.