Study Of Offshore Ghost Extracting And Imaging Methods

There is a great potential of sea oil reserves as it has a large scale of entrapment and a big yield.With the continuous improvement of exploration and development technology,marine seismic exploration has become the focus of the world.Seismic exploration is the main technology exploration at present.Compared with the onshore exploration,the existence of the sea water layer causes the complexity of seismic reflection characteristics and one of the main problems is the ghost waves.We always make ghost waves as noise in the conventional seismic data processing.In order to solve this problem,it develops a large number of methods in acquisition to remove ghost waves and promoting in imaging.However,ghost waves is also the reflection of the underground subsurface geology,it will reduce the accuracy of exploration if we simply abandon it.Therefore,it is necessary to carry out the research on the prediction and imaging of ghost waves.We propose a prediction of ghost waves based on its characteristics by improving Radon transform and consider the optimization problem of the prediction parameters.We make a detail of the prediction process of virtual reflection and decompose the extraction process after prediction.The matching subtraction technique is used to judge whether the extracted one is ghost wave.At the same time.We use curvelet transform in order to eliminate the multiple wave interference and classify the different ghost waves,and also realize RTM of ghost waves based on imaging cable.It can be seen from the model verification and the actual data test that the prediction methods of ghost waves after improving are more accurate and reliable.At last we summarize that ghost waves together with single refection to migration imaging can get better imaging accuracy.