用多次波压制模拟确定观测系统设计参数

The determination of parameters of layout system by multiple suppression simulation

1. 中国地质大学地球物理系,武汉430074;2. 中原油田勘探局勘探开发研究院,濮阳457001

Dept. of Geophysics, China University of Geosciences, Wuhan 430074

伊宁凹陷主要沉积的侏罗系煤系地层与砂岩地层交互,地震波在该地层中会产生全程或层间多次反射波。为了获得煤系地层下方岩层反射波的信息,必须在多次反射波压制效果与一次反射波叠加效果之间折衷地选择合适的采集参数。为此,基于伊宁凹陷已钻探井及初探地震剖面构制地质模型,应用适用于复杂介质的多次波快速正演模拟方法,模拟了野外地震记录的采集;进而选用不同的偏移距、排列长度、覆盖次数等参数,进行多次波压制处理。通过比较分析,确定出最佳观测系统设计参数。

The Yining Depression deposits mainly Jurassic alternating layers of coal and sandstone. Long-path and peg-leg multiples can be generated when seismic waves travel through such layers. In order to obtain seismic information under coal measure strata, tradeoff between the effects of multiple suppression and stacking of primary waves is necessary to achieve proper acquisition parameters. In this paper, we constructed a geologic model based on available drilling and seismic information, and simulated the acquisition of field seismic data with methods that can account for multiples in complex media. The optimal parameters of layout system are determined by comparison of multiple suppression with different parameters of offset, length of spread, and fold coverage.