【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。更多还原

【Abstract】 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.更多还原