超浅层地震勘探在青岛王哥庄断裂探测中的应用

The Application of Ultra Shallow Seismic Survey on Wanggezhuang Fault in Qingdao

目前国内外对目标层埋深仅有几十米(甚至十几米)的超浅层地震勘探经验不多,理论研究也不够深入。本文从城市活断层探测的角度出发,利用地质学、地球物理学及数学等学科中的相关理论和方法,探讨超浅层地震勘探在青岛复杂地质构造背景下取得有效探测结果的前提条件,并对青岛市主要活断层的典型剖面进行重点研究,力求在城市活断层超浅层地震勘探数据采集技术、数据处理等方面有所进展,为青岛及类似地质构造背景的地区开展活动断层超浅层地震探测提供参考。研究表明超浅层地震反射波法可以获取深度仅有十几米的地层反射信号,且大部分反射剖面都可较清楚地揭示出超浅部断层位置和断层特征。

At present for the target at depth of only tens of meters of ultra-shallow seismic exploration do not have many experiences in practice neither in theoretical research. The depth about decades of meters below the ground surface is the blind area of every kind of deep and shallow seismic exploration, which plays an important role in the research of the location of fault and active structure. Starting from the point of view of detecting urban active faults, we apply related theories and methods of geology and geophysics, probe into the precondition to acquire efficient ultra-shallow seismic results in complicated geological background. Taking the Qingdao area as an example, we study the depth condition of Quaternary deposits, and apply 4-8 stacking folds to satisfy the requirement to get the exploration results with high-resolution and high-SNR. Preliminary results reveal that the selecting proper surveillance layout is one of the keys to acquire authentic exploration results in ultra-shallow P-wave reflection exploration. Our results also show that ultra-shallow seismic reflection method in detecting faults in the Qingdao area has good application prospects.