散射地震二维观测系统研究

Research on 2D Seismic Scattering Observation System

传统地震观测系统以反射波理论(即假设地下介质为均匀层状介质)为基础,常用的有共中心点(CMP)、共反射点(CDP)观测系统等。随着勘探的不断深入,对勘探效果和效率提出了更高的要求。目前,工程地质调查中常用的观测系统需要布设大量接收点并进行多次移动,工作成本高且效率低。针对这一问题,本文进行了散射地震观测系统的探索研究,基本思路为以散射理论(即假设地下介质为散射点的集合)为核心,在实现二维频域数值模拟和全波形反演的基础上,设计模型和二维散射地震勘探观测系统,研究观测系统中道间距、炮间距等参数变化对勘探效果的影响。试验结果表明,相较于传统反射地震观测系统,散射观测系统只需要少量的激发点和接收点便能得到较好的勘探效果,有利于降低工作成本、提高工作效率。

The traditional seismic observation system is based on the theory of seismic reflected waves(which is assuming that the underground medium is horizontal layered),such as CMP and CDP.With the deepening of exploration,higher requirements are put forward for exploration effect and efficiency.In the current engineering geological survey,the observation systems need to deploy a large number of detectors and carry out multiple movements,so the work cost is high and the efficiency is low.Aiming at this problem,this paper was based on the scattering theory(which is assuming that the underground medium wasthe set of scattering points)and conducts an exploration study of the seismic scattering observation system,researching the influence of track interval and shot interval.The experimental results showed that,compared with the traditional reflection seismic observation system,the scattering observation system only needed a small number of excitation points and receiving points to achieve better exploration results,which was conducive to reducing work costs and improving work efficiency.