基于波场外推和阈值截断的鬼波压制方法

A ghost suppression method based on wavefield extrapolation and threshold truncation

本文分析一种基于波场外推和阈值截断的鬼波压制算法,该算法对含鬼波的地震数据进行两次波场外推,并对结果进行求和及阈值截断处理,得到水面处地震数据;然后利用该数据再次进行波场外推,得到鬼波和一次波,并将其从输入数据中自适应减掉,得到一次波和鬼波。该方法利用水速信息进行波场外推,完全数据驱动,不需要任何地下介质信息,可以分别对震源鬼波和检波器鬼波进行压制。模拟数据和实际数据验证了方法的有效性。

We propose in this paper a ghost suppression method based on wavefield extrapolation and threshold truncation.We first conduct two wavefield extrapolations to seismic data with ghosts,sum the extrapolation results,and truncate it using a threshold value.So seismic data at the sea level is calculated.Then we conduct another wavefiled extrapolation to the truncated results,calculate ghost and primary wavefiled which are adaptively subtracted from the input data,so primary and ghost are separately obtained.This process can be iterated until certain accuracy is fulfilled.The method requires water velocity only,and it is totally data driven,no subsurface information is needed.It can be used both for source-side and receiver-side deghosting.Tests on synthetic and real data illustrate the feasibility of the proposed method.