Study On High-precision Method Of Shallow Profile Seismic Data Processing And Interpretation

The shallow profile prospecting is a continuous walking and sailing detection method based on acoustic principles. It can get high resolution profiles with high frequency source. The processing of shallow profile seismic is usually only through the treatment of the acquisition system and the follow-up processing method is simple. When detections are carried out at sea, all kinds of noise interference low signal to noise ratio so as to the continuity of profile events is poor and the geological features are not obvious. In addition, sea multiple waves develop. It's more difficult to track layers effectively. The interpretation of shallow profile seismic data has been used the personnel manual horizon calibration and structural interpretation. The method can't make full use of the vertical and horizontal lines seismic data information. It isn't easy to identify small structures, so the interpretation is less efficient and the accuracy is not high enough.The thesis firstly focused on the shallow profile seismic data processing shortcomings. According to the actual data, the seismic characteristic of shallow profile is analyzed. Based on the theory of high-precision seismic, reasonable, practical and fidelity processing method is studied and the shallow profile high-precision processing flow is designed. The resolution of shallow profile is relatively high, so the principle of the high-precision processing is mainly to improve the data SNR, in the same time resolution and fidelity are taken into account. The compression noise methods are comprehensively used to suppress linear noise, such as band-pass filter, FK domain signal enhancement and weighting summation of adjacent traces, etc. The select of treatment parameters is the key to high-precision processing. According to the formation mechanism of multiple wave and the shallow profile seismic features, predictive deconvolution is used to suppress seabed reverberation and layer multiple in the condition of ensuring the resolution. Finally time-varying spectral whitening is used to improve resolution and RNA is used to improve SNR, making a final modification of the profile. The high-precision processing flow of the shallow profile seismic technically supplements the current lack of processing.The seismic attributes technology and the three-dimensional visualization technology are used in the shallow profile seismic interpretation for the first time. The two kinds of interpretation way could make full use of the vertical and horizontal lines seismic data information. The time to depth conversion method, the wave group characteristics method and the regional geological structure inference method are combined to calibrate layer. Based on that, the three-dimensional visualization technology integrates all the layer information and improves the rationality and accuracy of interpretation. The RMS amplitude between layers shows the lithology changes. Finally the shallow stratum is fine-divided and described. The flexible approach should be chosen in the fault interpretation according to the profile characteristics. Binning channel display to increase the channel spacing determines the major fault. Integrating the changes of upper and lower strata and the changes of adjacent survey lines events determines the small fault. The fault combination rules and the coherent body of information technology are used in the fault plane combination. Contrast with the past personnel manual interpretation way, the efficiency and accuracy are both improved.