哈拉湖地区浅层地震勘探可控震源激发参数对比试验  

Comparative test of vibroseis excitation parameters for shallow seismic exploration in Har Hu area

作　　者：吴华[1] 张保卫[2,3] 王凯 岳航羽[2,3] 张凯 WU Hua;ZHANG Bao-Wei;WANG Kai;YUE Hang-Yu;ZHANG Kai(School of Science,Chang＇an University,Xi＇an 710064,China;Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang 065000,China;National Center for Geological Exploration Technology,Langfang 065000,China)

机构地区：[1]长安大学理学院,陕西西安710064 [2]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000 [3]国家现代地质勘查工程技术研究中心,河北廊坊065000

出　　处：《物探与化探》2018年第5期1033-1041,共9页Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(41874123;41004043);陕西省自然科学基金项目(2016JM4003);长安大学中央高校基金项目(300102268402);中国地质科学院基本科研业务费项目"主动源和被动源面波联合勘探方法技术研究"(YYWF201634)

摘　　要：哈拉湖地区属于青藏高原冻土区,地质调查结果表明该地区具有良好的天然气水合物赋存条件和找矿前景,因此在试验区开展了高精度的浅层反射地震试验,激发震源选用KZ-28大型车载可控震源。通过分析试验区地震地质条件,结合本次浅层地震勘探的探测深度和目的层反射波特点,在地震剖面采集前,对可控震源的台数、扫描频率、扫描长度、振动次数和驱动幅度进行了试验研究,对不同的单一激发参数试验得到的地震记录进行对比分析,在满足探测要求的前提下,以最大限度地提高地震记录分辨率和信噪比为目的,确定了该地区地震勘探可控震源的最佳激发参数为:可控震源台次1台2~3次,扫描频率8~100 Hz,扫描长度12 s,驱动幅度75%。Har Hu area is a part of the frozen soil region of the Tibetan Plateau.The results of geological survey show that there exist favorable accumulation conditions and prospecting potential for gas hydrate in this area.Therefore,high-precision shallow seismic reflection experiments were carried out in this area,with the selection of KZ-28 large vehicle-borne Vibroseis. By analyzing the seismic geologic conditions of the test area in combination with the depth of the shallow seismic exploration and the characteristics of the reflection waves of the target layer,the authors studied the number of the vibration sources,the scanning frequency,the scanning length,vibration number and the driving amplitude before the seismic profile acquisition,and the seismic records obtained by different single excitation parameters were compared and analyzed.Under the prerequisite of satisfying the detection requirements,the seismic exploration can be determined for the purpose of maximizing the seismic record resolution and SNR.The optimal excitation parameters of the Vibroseis are 1 vibrator,2 ~ 3 sweeps,the sweep frequency is 8 ~ 100 Hz,the sweep length is 12 s,and the drive level is 75%.

关 键 词：可控震源 激发参数 扫描频率 扫描长度 驱动幅度 

分 类 号：P631.4[天文地球—地质矿产勘探]