薄砂岩储层多波叠后地震反射特征分析及应用  

Post-stack multi-wave reflection characteristics of thin sand reservoirs

作　　者：符志国 李忠 赵尧 蔡谦 李德珍 

机构地区：[1]中国石油集团川庆钻探地球物理勘探公司,四川成都610213 [2]中国石油集团山地地震技术试验基地,四川成都610213

出　　处：《石油地球物理勘探》2017年第5期1016-1024,共9页Oil Geophysical Prospecting

基　　金：国家科技重大专项(2011ZX05019-008-06)资助

摘　　要：影响储层多波地震叠后反射特征的因素很多,针对研究区的地质问题,重点分析了观测系统的炮检距、地震子波主频、储层垂向分布位置、围岩、储层厚度等5项因素。建立了一套以多波叠后反射特征正演分析、多波地震属性专家优化、多波属性融合为主要手段的薄储层预测方法。通过分析薄储层多波地震叠后响应特征,得到以下认识:(1)在分析储层的地震响应特征时,应建立在其他非储层因素相对稳定的基础上,才能较为准确地识别储层的地震响应;(2)薄含气砂岩储层呈弱反射信号,常被掩盖在砂、泥岩性界面的强反射之中,而联合多波信息是提高储层描述精度的一种有效途径;(3)在钻井样本数量很少、不便于使用自动化储层模式识别方法时,充分发挥针对具体研究目标的先验信息、数字特征与目标的相关性等专家知识,采用多波属性方法刻画储层是可行的。Many factors may affect on post-stack multi-wave reflection characteristics.To seek the solution to geological problems in our study area,five factors,such as offset of seismic acquisition geometry,wavelet dominant frequency,reservoir vertical distribution,surrounding rocks,and reservoir thickness,are argued in detail.A suit of thin reservoir prediction methods are constructed such as forward modeling of post-stack multi-wave reflection,multi-wave attribute expert optimization and fusion.Based on our study,the following conclusions are drawn:(1)When analyzing reservoir characteristics,the identification of reservoir seismic response pattern should be based on the stable non-reservoir factors;(2)The reflection of thin gas sand is weak,and is usually covered in the strong reflection of shale-sand lithology interface.Combination of multiwave information is an effective way to improve the precision of reservoir description;(3)When the automatic reservoir recognition does not work due to lack of well samples,it is feasible to describe reservoirs by multi-wave attributes together with specified target prior information and expert knowledge.

关 键 词：薄含气砂岩 多波 叠后 反射特征 正演 地震属性 

分 类 号：P631[天文地球—地质矿产勘探]