| Nowdays the challenge of seismic E&D needs the techniques of high accuracy,high definition,high confidence;this gives rise to quick development of borehole seismic technique,though at present the cost of no matter VSP or crosswell is higher.How to get P/S wave from complex borehole seismic record and crosswell seismic imaging are hot research point of crosswell seismic data processing.Based on the acquisition of 3C borehole seismic, we research the separation of P and S waves, extract P and S wave component, and study wave equation imaging methods. Depending on principle of high resolution frequency domain radon transform, according to the characters of crosswell data such as: high sample rate, wide spectrum, high main frequency quantity, we research high resolution radon transform; corresponding processing program are developed and various parameters are tested and adjusted. Considering the specific feature of 3C borehole seismic acquisition system and the difference of P and S wave in polar nature, we utilize high resolution forward/inverse radon transform to develop the P/S wavefield separation method in ? ?pdomain, and design corresponding program.Processing of simulated data of theoretical model and practical crosswell model separates P/S wavefield successfully. In the basis of extracting P and S wavefield, depending on data structure of existing crosswell seismic processing system, we transplant wave equation finite-difference migration method into crosswell seismic data processing. Considering the character of crosswell seismic, we grid the crosswell section, calculate imaging time by ray-tracing, use finite-difference method to achieve crosswell wavefield reverse time continuation, and finally apply imaging condition to get finite-difference reverse-time migration profile. Processing results implies that imaging from extracted P/S wavefiled can reflect actual attitude of strata actually, and the imaging results have high resolution and high S/N.
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