Research And Application Of Key Processing Methods For Land(Mountain)Three-Dimensional Multi-Wave Seismic Data

Multicomponent seismic which is one major field of seismic exploration has made a great progress on instrument manufacturing,acquisition geometry,processing method and integrated interpretation in recent years.Owing to its unique advantage on reservoir characterization,fluid identification,fracture prediction and several successful applications,multicomponent seismic is attracting more and more companies home and abroad to focus on its development.Although the research and application of multicomponent is better than ever,it still faces with some technical problems and needs to conquer the key aspects,such as multicomponent seismic data vector denoising,converted wave static correction,joint P-and S-wave processing,multicomponent anisotropic velocity model construction,and converted wave prestack time migration.First,in order to eliminate the influence of the instrument,acquisition geometry and data quality on the land multicomponent seismic data,we analyzed the situation faced with prestack denoising and theoretically studied the processing method of high quality vector denoising on the land multicomponent seismic data.By comparing with the traditional processing method,we presented abnormal amplitude suppression method based on the decibel criterion of time-frequency space and polarization filter vector denoising method based on joint attributes.Then we verified the method using numerical and real seismic data,which proved to be great and successful.Second,the problem of land P-SV wave static correction is the low signal to noise ratio,the large time correction and the big lateral heterogeneity.Considering the characteristics of the land seismic data and the traditional converted wave static correction,we presented a converted wave static correction method which is adapt to land seismic,less confined and easy implemented.We figured out the mechanism of converted refraction wave,the occurrence condition as well as type of the first arrival waves,the identification criterion and picking method based on the research of joint elastic wave refraction static correction method.Then we constructed a converted wave static correction processing flow and verified the method with real seismic data.Further,in order to solve the 3D converted wave prestack migration problem such as the asymmetry of the ray path,the coupling between P-wave and S-wave velocity,the large offset(X/Z>1)of the converted waves,and the medium anisotropy.Based on the VTI model,we presented a series processing flow consisting of gather extraction,multicomponent wave velocity analysis,NMO,stack,migrated velocity analysis and Kirchoff prestack time migration.Then we verified the processing flow with real seismic data and industrial exploration.The result and the efficiency can satisfy the condition of basic industrial processing.In order to apply our method to industry process,we developed the corresponding software module.To test the adaptability of the key processing method and the practicality of the software module,we processed a new and integral 3D land seismic data.The square of the field is nearly 100 km~2 and the imaging result is nearly 70 km~2.The final result of tying seismic refection horizon to geologic horizon shows that the processing method can meet the satisfactory of structural interpretation and verifies that the software module can be applied to the industrial processing.In summary,the three key processing method we focused on for 3D land multicomponent seismic is the key point of the converted wave processing.It directly influences whether the converted data can provide the reliable and valuable proposal.The research and achievements of the thesis are a kind of active exploration and promotion of the industrial application of multicomponent seismic exploration,which has reached the goal of the thesis.