Abstract: The complexity of surface and subsurface structures makes Kuqa complex and cliffy structural trap be difficultly ascertained. Since 2005, the stress has been placed on study of complex mountainous seismic exploration technique, especially related seismic acquisition and fine velocity modeling techniques, and finally establishing a systematic method for ascertaining complex cliffy structural traps. This paper presents the method, including the seismic acquisition technique for ascertaining structural style, the superficial velocity inversion modeling technique, T₀ drift correction technique and variable velocity mapping technique, for determination of cliffy structural traps. Also, the prestack depth migration outcome at the main part of structure is used to make a correlation and validation for the purpose of improving the precision of ascertaining the complex cliffy structural traps. The application of this method to complex mountains in Tarim basin receives good effectiveness.

Key words: cliffy structure, complex mountain, seismic acquisition, T₀ drift, secondary interference, graphic migration