METHOD AND APPARATUS FOR SEISMIC SIGNAL VELOCITY DETERMINATION

摘要

A method for determining actual velocities of seismic events occurring on plural seismic traces by deriving a trace coherence factor which varies directly with signal velocity. The method consists of processing move-out-corrected, plural seismic traces at a plurality of different time delay per trace relationships to establish a coherence factor at each time delay per trace. The coherence factor is arrived at for each probable velocity by summing all trace values and then finding a respective difference value as between each of the trace values and the sum value, which difference values are further processed by summation of their absolute values for derivation of a reciprocal trace value. The reciprocal trace value is then utilized as a gain control factor for controlling time variation of the amplitude of summed seismic traces, and the output trace value so controlled constitutes an accurate indicator of coherence of events occurring at the selected velocity.