山地三维地震采集过障碍观测系统设计的改进方法

IMPROVED METHOD IN THE DESIGN OF 3-D SEISMIC GEOMETRY IN LARGE OBSTACLE MOUNTAIN AREA

高陡构造地区地震勘探中,在山地大型障碍区布设观测系统,为避免因地表障碍物使地震反射剖面出现间断,需要动态调整观测系统设计增加短炮线,跨越大型障碍物(水库,矿区等),以确保面元属性均匀,压制噪声最佳,以得到好的反射地震资料。在参与和研究野外实际的过障碍观测系统的基础上,提出一套采用增加短接收线代替增加短炮线的方法。基本思路是:在绿山软件上进行理论推导,合理动态调整物理点的位置。在穿越大型障碍区的地震勘探中,采用增加短接收线代替增加短炮线的方法,能成功解决施工高成本,有效激发难,以及激发风险等难题,确保获得高信噪比的地震资料。

In high-steep structure area seismic exploration,layout observation system in the large obstacles mountain area needs to be dynamic adjustment observation system design in order to avoid seismic reflection profile appeared discontinuous because of surface and to cross over obstacle (the reservoir,mining area etc) to ensure the bins to have uniform attributes and optimally depress the noises and gain good reflection seismic data.The content of paper is based on participating in the research of observation system in the large obstacles area and present a set of methods from optimal adjustment physical points that receiving-lines replacement shot-lines.The basic ideas as follows:using Green Mountain Design software and seismic surveying result to do repeated adjustment of dynamic designed regular geometry to avoid the obstacles as far as possible and to compute distributed situation of folds,offset and azimuth and design irregular geometry suitable for obstacle areas.Some designing principles are summarized associated adjusted methods and auxiliary tools are given in the paper.The method of save cost,effective receiving and shooting in safety way going through larger obstacles is proposed which successfully solve the problems by reasonable configuration and adjustment of shot-points and receiver-points,and ensure the high signal to noise ratio of seismic data.