Abstract: This paper presents the sequence division scheme of Jurassic in Wu-Xia area in northwestern margin of Junggar basin by means of logging-seismic data analysis and well-connecting framework sequence analysis, through the seismic, drilling and well log data to find out the identification marks of the sequence boundaries. The result shows that the Jurassic system could be divided into two supersequences and seven sequences. The first super-sequence includes JSQ1, JSQ2, JSQ3, JSQ4 and JSQ5, corresponding to the Badaowan and Sangonghe formations of Lower Jurassic and the Xishanyao formation of Middle Jurassic. The second super-sequence includes JSQ6 and JSQ7, corresponding to the Toutunhe formation of Middle Jurassic and the Qigu formation of Upper Jurassic. All the sequences occur in a cycle of early retrogradation and late progradation in plane. The strata characteristics are resulted from combination of sedimentary formation and reformation.

Key words: Junggar basin, Wuerhe-Xiazijie area, Jurassic, stratigraphic sequence division, sequence boundary