羌塘盆地浅层地震探测方法技术

西藏羌塘盆地地震地质条件复杂,要取得高质量的浅层地震勘探资料是非常困难的。文中结合多次在羌塘地区开展的浅层反射地震勘探方法技术试验,探讨了高原冻土层对地震资料的影响因素,地震数据采集采用了小道间距、多道数长排列的接收方式,同时提高覆盖次数,采用大吨位可控震源进行高频激发,获得了高质量的原始数据资料;在地震数据处理阶段,重点在叠前采取相应的去噪处理技术,能够有效地衰减震源干扰波、随机和相干噪声等干扰,获得信噪比较高的地震成像剖面。总结研究区浅层地震勘探的数据采集方法和资料处理解释技术,取得了较好的试验研究成果,对今后在高原冻土区开展浅层地震勘探方法技术的应用与研究有一定的借鉴作用。

The method for shallow seismic exploration in Qiangtang basin

Due to complex seismic?geological conditions,it is very difficult to acquire high quality results of shallow seismic exploration in Qiangtang basin of Tibet. In this paper,through the experiment of shallow seismic exploration technology in this area,the authors dis?cussed the interference of the permafrost layer to the seismic data.In seismic data acquisition,a smaller channel spacing should be a?dopted,with a number of long arrangements of multi?channel receiving mode.In addition,the number of CDP stacking is increased,and a large tonnage high frequency vibrator is utilized for high?frequency excitation.In this way,a higher quality of raw seismic data can be obtained.In seismic data processing stage,we can use the corresponding de?noising technology before CDP stacking,which can effective?ly suppress various interference waves,such as random noise and coherent noise.The acquisition method and processing technology of 2?D shallow seismic survey is tentatively summarized,and the experimental study has achieved good results. The results achieved by the authors have certain reference value for application and study of shallow seismic exploration technology in plateau permafrost area in the future.