The Study Of Cross-well Seismic Conventional Imaging Method Technology When The Interface And Wells Are Decline

The cross-hole seismic has obvious accuracy advantages in solving the reservoir development problems, and it can obtain seismic signals with extremely high resolution, so we can get finer imagine of the small scale geological objects such as the structure cross-holes and reservoirs。It makes connection between the surface 3D high resolution seismic and the well logging and reservoir geology, also provides a new effective finery exploration method for oil development。There are three parts in cross-hole seismic:pre-process, chromatography inversion and imagine of reflection wave。The imagine of reflection wave is the key step of the cross-hole seismic data process, also is an effective method of inversing geology model。Similar with the surface seismic, the important premise of reflection wave imagine is having known the velocity model of the cross-hole stratum。At present, the ways of determine velocity parameters are acoustic well logging, tomography and cross-hole reflection wave stack velocity analysis。Cross-hole reflection wave imagine has its unique advantages:firstly, the frequency of cross-hole seismic data is extremely high, and the main wave number can achieve 100-200 (1/km), and the main frequency can achieve 125-250Hz。Applying these imagines, we can finely characterize the construction details of sub-surface and the construction features of reservoirs。Secondly, different with the surface seismic, the cross-hole seismic reflection profile is in the depth domain, so it can be compared with well logging data and drilling data directly。Basing on the advantages of cross-hole reflection wave imagine described above, this paper discusses and studies the traditional imagine methods deeply, derives the 3D reflection wave time-distance equation in the declining interface when the two wells are decline and the connection line of the two wells is not vertical to the stratum alignment; revises and improves the algorithms of velocity analysis which only can be applied in the level stratum before, derives the algorithm model of cross-hole converted wave reflection points preliminary, and reduce the power of the converted wave time-distance equation to increase the velocity of second wave velocity analysis。Paper completes the computing method programs by using Visual C++ 6.0 and QT3.3.2.。The test results of cross-hole model and practice data is good enough and that shows that the imagine method is effective and practical。...