Development of a numerical algorithm for solving the problem of processing and determining the basic velocity model

Abstract

This work is devoted to development of an automatic algorithm for determining the velocity model from the data of the field seismic profile. First of all total energy of received signal and the positions of the first arrivals of reflected waves has to be determined. The traces sort by common depth point and the spectra of possible velocities determine at each point of the trace and each assembly of the common deep point. The procedure is fully automated and as a result, instead of about 150 points of manual processing, 4 million points are obtained on the test profile. The values of chosen effective speeds correspond not only to existing criteria for their determination, but also to requirement of smoothness in first derivative. This makes it possible to determine reliable interval velocity profile at each track point and each collection of the common depth point. Speed determination accuracy in the range of 10-50 m/s. After recalculating the time profile into a depth profile, it becomes possible to obtain high-resolution and detailed model of the velocity structure of the geological profile during migration transformations. An iteration process refines the calculations obtained by geologists and geophysicists in order to obtain consistent and consistent results.