Abstract: In some area where the velocities in sandstone and mudstone are very close, and even are the same in some stratums, and the values of gamma well logging in sandstone are high that cannot be distinguished from mudstone's, the sandstone's characteristic spread cannot be detected in common ways of wave impedance inversion and gamma inversion. Though the instantaneous amplitude has something correlated with the reservoir distribution, human error may be made when recognizing the instantaneous amplitude information on account of noise. According to these problems, based on the instantaneous amplitude extraction and coherence analysis theories, instantaneous amplitude coherence analysis method is applied to the illustration area-the Shahejie formation, Western sope, Eastern sag, Liaohe basin. Under the restriction of well data, reservoir's landscape orientation prediction was reached with this method.

Key words: instantaneous amplitude, coherence analysis, reservoir prediction