关中盆地新近系蓝田-灞河组热储层物性及渗流特征研究  

Physical properties and percolation characteristics of Neogene Lantian-Bahe Formation thermal reservoir in Guanzhong Basin

作　　者：张莹 任战利[1,2,3] 兰华平 祁凯 邢光远[1,2] 夏岩 ZHANG Ying;REN Zhanli;LAN Huaping;QI Kai;XING Guangyuan;XIA Yan(State Key Laboratory of Continental Dynamics,Northwest University,Xi’an 710069,Shaanxi,China;Department of Geology,Northwest University,Xi’an 710069,Shaanxi,China;Key Laboratory of Exploration and Development of Multiple Energy Resources,Xi’an 710069,Shaanxi,China;Exploration and Development Research Institute of PetroChina Changqing Oilfield Company,Xi’an 710018,Shaanxi,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,Shaanxi,China)

机构地区：[1]西北大学大陆动力学国家重点实验室,陕西西安710069 [2]西北大学地质学系,陕西西安710069 [3]西安市多种能源资源勘探开发重点实验室,陕西西安710069 [4]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [5]低渗透油气田勘探开发国家工程实验室,陕西西安710018

出　　处：《地质通报》2024年第5期712-725,共14页Geological Bulletin of China

基　　金：国家重点研发计划《未固结砂岩热储层保护与增效钻完井技术及材料》专题《不同地区典型未固结砂岩热储层特征及评价》(编号:2019YFB1504201-01);长庆油田分公司勘探开发研究院合作项目《关中盆地地热资源调查及开发技术政策研究》。

摘　　要：关中盆地地热资源丰富,开发利用地热能有助于调整能源结构、降低雾霾及改善环境。新近系蓝田-灞河组是目前地热开采的主要热储层,明确储层物性及渗流机理对地热资源的高效规模开发利用及回灌具有重要意义。通过钻井岩心及测井资料,结合压汞、铸体薄片、核磁共振等相关测试手段,对渭河盆地新近系主要层位蓝田-灞河组的物性特征、孔隙结构特征、渗流特征进行了详细分析。研究结果表明:①基于地热井及钻孔测井资料,西安凹陷蓝田-灞河组孔隙度为20%~25%,渗透率为100~200 mD,固市凹陷孔隙度为10%~20%,渗透率为1~100 mD,西安凹陷物性条件优于固市凹陷,在平面上孔渗均表现为由盆地边缘向盆地中部增大的趋势。②蓝田-灞河组孔隙以原生粒间孔、粒间残余孔隙为主,局部见少量微裂缝发育,见少量长石溶孔。孔喉分布比较均匀,主要介于10~16μm之间,渗透率贡献值高。出水量大,单位厚度砂岩单位涌水量高,富水性及渗流特征好。③蓝田-灞河组砂岩储层类型属于Ⅱ类储集层,综合评价为高孔隙度渗透层,是最有利的地热开发层段。Guanzhong Basin is rich in geothermal resources,and its development and utilization will help to adjust the energy structure,reduce haze and improve the environment.The Neogene Lantian-Bahe Formation is the main stratum exploited at present.It is of great significance for effective development and reinjection of geothermal energy to clarify reservoir physical properties and seepage mechanism.Through core data and logging data,combined with mercury injection,casting thin section,nuclear magnetic resonance and other related testing methods,the physical property,pore structure and seepage characteristics of the Neogene Lantian-Bahe Formation in the Weihe Basin are analyzed in detail.The results show that:①The porosity in the plane of Lantian Bahe Formation is 7%~30%,with an average of 15%;permeability changes greatly,0.05~5689 mD,generally more than 30 mD.②The pores of Lantian-Bahe Formation are mainly primary intergranular pores and intergranular residual pores,with a small amount of microcracks and feldspar dissolution pores can be seen locally.The pore throat distribution is relatively uniform,mainly between 10 and 16μm.The contribution value of permeability is high.The water yield can reach 80 m3/h,and the unit water inflow of sandstone with unit thickness can reach 0.0035 m3/(h·m2)with good water yield and seepage characteristics.③The reservoir type of Lantian-Bahe Formation belongs to ClassⅡreservoir,which is comprehensively evaluated as high porosity permeable layer,and is the most favorable geothermal development interval.

关 键 词：热储层 孔隙结构 渗流 蓝田-灞河组 地热资源 关中盆地 

分 类 号：P314[天文地球—固体地球物理学] P534.62[天文地球—地球物理学]