Abstract: Sand connecting scale in space is a key factor controlling size and abundance of lithologic trap. This paper presents statistic alanalysis of single well sand body and correlation of multi-well sand bodies integrated interwell logs with Kriging interpolation metrod, by which the connectivity evaluation of sequential sand spaces of Jurassic in northwestern margin of Junggar basin has been made, predicting favorable zones of the lithologic trap applying lateral distribution of sand content technique. Several conclusions are then drawn as follows:1)low sand content is favorable for forming lithologic trap, but thin sand thickness is hard to form large scale of lithologic trap; 2)taking relative isochronal horizon as a restricting condition, interwell log with Kriging interpolation can remarkably increase the accuracy of sand correlation; 3)in Grade Ⅱ sequence of Jurassic, it is much easier to form lithologic traps in Grade Ⅲ sequences of B and C, which lie in lake-transgressing period and the maximum lake-flooding period of GradeⅡ sequence, respectively, while it is more dificult to form lithologic traps in Grade Ⅲ sequences of A and D, which lie in lowstand and highstand periods of the Grade Ⅱ sequence, respectively; 4)the favorable zones forming lithologic traps are often located in areas with low sand content and quick declining toward updip direction.

Key words: Junggar basin, Jurassic, variation function, sand body, correlation, sandstone, percent, content, subtle trap