阵列声波测井在致密砂岩气藏含气性评价中的应用  

Array acoustic logging to evaluate gas-bearing property in tight sandstone gas reservoirs

作　　者：夏小勇 王跃祥 谢冰 赖强 韩冰 朱绍武 高义兵 XIA Xiaoyong;WANG Yuexiang;XIE Bing;LAI Qiang;HAN Bing;ZHU Shaowu;GAO Yibing(Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China;Southwest Company,China National Logging Corporation,Chongqing 400021,China)

机构地区：[1]中国石油西南油气田公司勘探开发研究院,四川成都610041 [2]中国石油集团测井有限公司西南分公司,重庆400021

出　　处：《天然气勘探与开发》2024年第3期77-84,共8页Natural Gas Exploration and Development

摘　　要：四川盆地中部地区天府气田中侏罗统沙溪庙组致密砂岩气藏是近年来勘探的热点和重点,但有别于常规砂岩气藏,此类气藏岩性复杂、储集条件差,常规的电法测井难以准确反映储层含气性的变化。选取阵列声波测井,进行曲线含气敏感性分析,优选纵波时差差值法、拉梅系数—体积压缩系数曲线重叠法,对储层的含气性进行评价。并进一步开展岩石不同饱和度状态下声速实验,探索通过阵列声波测井定量计算储层含气饱和度的方法。研究结果表明:①针对川中地区致密砂岩储层,基于阵列声波测井的曲线包络面法,相较于电法测井含气性测井解释符合率明显增加,能够较好地对致密砂岩储层含气性进行评价;②综合纵横波速度比和体积模量计算含水饱和度,与密闭取心得到的含水饱和度相关性较好,可为致密砂岩储层划分和参数计算提供依据,对四川盆地其他致密砂岩储层含气性评价具有指导作用。Tight sandstone gas reservoirs of the Middle Jurassic Shaximiao Formation,Tianfu gasfield,central Sichuan Basin,have developed into the hot and key exploration domain in recent years.Different from conventional ones,such reservoirs,however,have complex lithology and poor reservoir conditions.Some variations on their gas-bearing property cannot be accurately reflected by using traditional electrical logging.Thus,array acoustic data were used to analyze curve sensitivity to this property.And two methods of longitudinal wave moveout and Lame coefficient–volume compressibility curve overlap were selected for property evaluation.Furthermore,acoustic-wave experiments were conducted in rocks with different saturation to create one way to quantitatively calculate gas saturation using array acoustic data.Results show that(i)for the tight sandstone reservoirs in central Sichuan Basin,one way of curve envelope based on array acoustic data may achieve much higher coincidence of gas-bearing logging interpretation than electrical logging,and can better estimate the gas-bearing property;and(ii)combining the ratio of longitudinal-wave velocity to transverse-wave velocity(V_(p)/V_(s))and the bulk modulus,the calculated water saturation has a good correlation with that from sealed coring,which may not only provide basis for reservoir classification and parameter calculation but guide the evaluation on the gas-bearing property in other tight sandstone reservoirs in Sichuan Basin.

关 键 词：四川盆地 中侏罗世 致密砂岩气藏 阵列声波 含气性评价 曲线包络面法 纵横波速度比 

分 类 号：P631.81[天文地球—地质矿产勘探] P618.13[天文地球—地质学]