潍北地区特殊近地表结构对地震激发的影响分析  

Influence analysis of the special near-surface structure on seismic shooting in Weibei Area

作　　者：姚江[1] 徐钰[2] 荣毅[3] 贾静敏[2] 

机构地区：[1]中国石油化工股份有限公司石油工程地球物理有限公司,北京100728 [2]中国石油化工股份有限公司石油工程地球物理有限公司胜利分公司,山东东营257068 [3]中国石油化工股份有限公司胜利油田分公司地质科学研究院,山东东营257100

出　　处：《石油物探》2013年第2期177-183,113,共7页Geophysical Prospecting For Petroleum

基　　金："十二五"国家重大专项"精细勘探关键技术攻关与系统配套"项目(2011ZX05006-002)资助

摘　　要：潍北滩涂地区由于多条河流相互作用、大面积抽取地下卤水用于晒盐,造成近地表存在大量流沙层和空穴低速体等特殊表层结构,导致近地表速度、厚度、岩性纵横向变化非常剧烈,吸收衰减严重,地震激发下传能量弱。从近地表介质特征入手,构建模型模拟分析不同低速体大小和埋深、不同激发深度、不同围岩介质对地震激发的影响,提出了在平面上或纵向上优选胶泥激发的点位布设、尽量避开低速体或打穿低速体的激发因素选择方法,基本消除了多次波、低频干扰,地震资料品质明显改善。In Weibei tidal area,channel interaction and large-scale underground brine extraction for salt production leads to abundant special surface structures such as quicksand layers and hole low-velocity bodies,resulting in extremely seriously lateral and longtitual variation in near-surface velocity,thickness and lithology,serious absorption and attenuation,and weak down-going seismic shooting energy.Starting from near-surface media characteristics,geological structure model is built to simulate and analyze the seismic shooting effect with different-scale & different-buried-depth of low-velocity bodies,different shooting depth and different surrounding media.Then,we conclude the principles of layout and seismic source:preferred clay,avoid the low-velocity body or drill through the low-velocity body.The quality of seismic data has been improved;the multiples interference and low-frequency noises have been weakened according to the method.

关 键 词：近地表低速体 岩性结构 模型模拟 激发因素 

分 类 号：P631.4[天文地球—地质矿产勘探]