Abstract：A new stochastic hillclimbing(SHC) algorithm far paststack seismic trace inversion can be formed by using both the stochastic hillclimbing algorithm of Huanget al in 1995 and the new model that was derived from Ingber's temperature dependent pseudo-Cauchy distribution(1993).The basic principle of the method is that the objective function is defined as normalized similarity coefficient E,which is then made maximum by the wave impedance model derived from SHC inversion.In each new model construction using iteration,bath the sparse-point search at high temperature and the present model search at low temperature can be conducted,thus speeding up iteration and convergence.In SHC inversion of real acoustic logging data with noises and without noise,the similarity coefficient E is up to 0.99 after 44 iterations;and whether there is noise ar na,the inversion results are very similar to real curves.The method can be used to produce high-resolution wave impedance section and porosity.
