Abstract：Interval velocity is very important parameter,but it's hard to be accurately acquired. In many cases,traditional Dix formula hardly meets the requirement of precision in current exploration. Although the precision of interval velocity computed by currently developed prestack travel-time inversion andwave impedance inversion of poststack seismic traces has be greatly improved,but it has larger limitation when each method is used alone.The former has lower precision when it is used for thin-layer, that means,it is difficult to accurately compute the frequently variated interval velocity;on the other hand,the later easily causes the entirety excursion,i.e. the slowly variated interval velocity is not under control. Therefore,the paper studied on prestack and poststack joint inversion and used genetic algorithm to improve the precision inpoststackwaveimpedanceinversion.It is showed from test results of both theoretic data and real field data that the method has good effects.
