碳酸盐岩储层孔隙结构表征及储渗能力研究——以鄂尔多斯盆地靖边气田下古马五_(1+2)储层为例  

Characterization of Pore Structure of Carbonate Reservoirs and Study of Storage and Seepage Capacity of Them:Taking Lower Paleozoic Ma 5_(1+2) Reservoir in Jingbian Gasfield of Ordos Basin as an Example

作　　者：贾浪波 刘海锋[1] 薛云龙[1] 李琳[1] 韩豫锋 文远超[2] 高东[2] 谢姗[1] 田敏[1] 白铁峰 JIA Langbo;LIU Haifeng;XUE Yunlong;LI Lin;HAN Yufeng;WEN Yuanchao;GAO Dong;XIE Shan;TIAN Min;BAI Tiefeng(Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi 710018,China;No.1 Gas Production Plant,PetroChina Changqing)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [2]中国石油长庆油田分公司采气一厂,陕西靖边718500

出　　处：《西安石油大学学报（自然科学版）》2023年第4期38-46,共9页Journal of Xi’an Shiyou University（Natural Science Edition）

摘　　要：靖边气田下古马五1+2储层次产层(除过马五13之外其他小层)储量基数大,动用程度低。为此,利用岩心、铸体薄片、高压压汞、CT扫描、核磁共振以及充注实验开展了储层主次产层孔隙结构和渗流能力研究。结果表明:①基于储集空间的差异,可将下古碳酸盐岩储层划分为缝洞、孔缝、孔隙和裂缝型储层;②根据毛管压力曲线、CT扫描和核磁共振T_(2)谱分析,缝洞型和孔缝型储层平均孔喉半径最大,分选最好,平均孔喉配位数较高,可动流体多,连通性好,储渗能力强,裂缝型储层储集空间小,储渗能力较差,孔隙型储层主要为孤立孔隙,可动流体少,储渗条件最差;③通过充注实验分析,有利储层充注下限为0.02×10^(-3)μm ^(2),气源充注过程中,气体优先进入缝洞型、孔缝型储层,孔隙型和裂缝型含气量比较差,气源开采过程中,随着生产持续进行,缝洞型储层贡献逐渐降低,孔缝型和裂缝型储层贡献逐渐升高。综合分析缝洞型及孔缝型储层微观孔隙结构条件最好,马五13缝洞型和孔缝型储层占比最高,是其成为主产层根本原因,下一步开发次产层的关键是寻找缝洞型和孔缝型储层发育有利区。The secondary production layers(except the Ma 513 layer)in the Lower Paleozoic Ma 51+2 reservoir of Jingbian Gasfield have a large reserve base and low recovery degree.To this end,the pore structure and permeability of the main and secondary production layers of the reservoir were studied using core,cast thin sections,high-pressure mercury injection,CT scanning,nuclear magnetic resonance,and injection experiments.The results show that:(1)Based on the differences in reservoir space,the Lower Paleozoic carbonate reservoir is divided into fractured-vuggy,porous-fractured,porous,and fractured reservoirs.(2)According to capillary pressure curve,CT scanning and nuclear magnetic resonance T_(2)spectrum analysis,the average pore throat radius of fractured-vuggy and fractured reservoirs is the largest,with the best sorting,the highest average pore throat coordination number,more movable fluid,good connectivity and strong storage and seepage capacity;there are mainly isolated pores in the porous reservoir,with few movable fluid and the worst storage and seepage conditions.(3)According to the analysis of filling experiments,the filling lower limit of favorable reservoir is 0.02×10^(-3)μm^(2).During the filling,gas preferentially enters fractured-vuggy and porous-fractured reservoirs,with small gas content in porous and fractured reservoirs.During the gas production,as production continues,the contribution of fractured-vuggy reservoir gradually decreases,while the contribution of porous-fractured and fractured reservoirs gradually increases.Based on comprehensive analysis,the micro pore structure conditions of fractured-vuggy and porous-fractured reservoirs are the best.The proportion offractured-vuggy and porous-fractured reservoirs in the Ma 513 layer is highest,this is the fundational reason why it has become the main production layer.The key to the next step in developing secondary production layers is to find favorable development areas with fractured-vuggy and porous-fractured reservoirs.

关 键 词：孔隙结构 岩溶碳酸盐岩储层 储层类型 储渗能力 充注实验 鄂尔多斯盆地 

分 类 号：TE122.23[石油与天然气工程—油气勘探]