莱州湾某区块浅部地层地震反射异常原因探讨  

Discussion on seismic anomalous reflection in shallow strata in the Laizhou Bay

作　　者：刘双双[1] 朱友生 周松望[1] 刘剑涛[1] 郝高建[1] 陶华[1] 

机构地区：[1]中海油田服务股份有限公司物探事业部,天津300451

出　　处：《海洋学研究》2017年第3期34-41,共8页Journal of Marine Sciences

摘　　要：渤海莱州湾某区块采集的三维地震资料出现反射特征杂乱、同相轴连续性差等现象,对该区块浅部地层进行了电火花物探调查,并在地震资料异常区和非异常区分别选取1个位置进行钻孔,同时对海底面以下150 m范围内的土层进行连续的地质取样。通过对物探和地质资料的综合对比分析,判断造成研究区浅层地震资料反射异常与下述几个方面因素有关:(1)研究区处于莱州湾凹陷东部走滑断裂带内,浅部地层受深部断裂系统影响发育许多小断裂;(2)研究地层中富含大量的浅层气;(3)与邻近区块对比,所揭示浅部地层的土质性质十分异常,土层强度和剪切波速等均明显偏大。Reflection feature and seismic event continuity appeared in 3D seismic acquisition data was cluttered and poor in one study region of the Laizhou Bay. The sparker investigation was carried out in shallow strata and two geological borings were drilled in the abnormal and normal region respectively, at the same time, the strata were sampled entirely from 0 m to 150 m below the seabed. Through comprehensive comparison and analysis of the geophysical data and geoteehnical data, it is clear that anomalous seismic reflection in shallow strata of the study region relates to various influence factors below： （1） The study region is in the eastern Laizhou Bay Sag strike-slip zone, and therefore many small faults which were affected by the fault system were developed in the shallow strata. （2） An amount of shallow gas was revealed in the shallow strata. （3） Comparing with the shallow strata of nearby region, the soil characteristic was anomalous in the study region; the soil strength and shear wave velocity were significantly larger.

关 键 词：异常反射 影响因素 地质构造 土质特性 浅层气 

分 类 号：P631.4[天文地球—地质矿产勘探]