Abstract: The velocity spectrum data from Fudong slope belt in eastern Junggar basin are analy zed and interpreted, the compacting models oftwo types of detailed sandy mudstone using drilling and well log data are developed. Based on these, the conversion of interval velocity,correction of spectrum-based interval velocity and correction and smoothing of sand exponential-calculated error are conducted using seismicvelocity lithological interpretation system (VLIS), obtaining the estimated interval velocity and sand exponent of Mid-Upper Jurassic Shishugougroup, respectively. Through seismic interval velocity analysis and lithology prediction, integrated with characteristics of seismic facies andsedimentary facies, the high sand exponent areas are corresponding to foreset and filled facies, which reflect that the source in this area is mainlyfrom deposits to east-north direction, and provide quantitative basis for predicting the favorable reservoir facies belts in Fudong slope belt.

Key words: Junggar basin, velocity spectrum, interval velocity, lithology interpretation, prediction