doi: 10.3981/j.issn.1000-7857.2015.03.004
By analyzing plentiful geological and geophysical data and based on the fundamental principles of sequence stratigraphy and sedimentology, the isochronal framework of sequence stratigraphy and sedimentary system model of Triassic in Hong-Che area of Junggar Basin have been established. The whole Triassic is divided into five third sequences (TSQ1-TSQ5), among which TSQ2 is lower Karamay formation and TSQ3 is up Karamay formation. It is found that Triassic plate is in the evolution of the foreland basin stage, and has moderate tectonic activity. It's different to identify Ffs but easy to identify Mfs in sequence, transgressive systems tract and highstand systems tract. According to the tectonic development of the background and type of depositional system of northwestern margin of Junggar Basin, and combined with the evolution characters of sedimentary facies, a developing mode of Triassic in the study area is established. Through sequence control factor, basin tectonic activity, climate and lake level fluctuation are found, which have apparent control action in sequence. At last, the paper discusses the relationship of the sequence stratigraphy and lithologic trap, and points out that in TSQ2 period, as flood plain developed, it had high shale content, thus favored buildup of lithologic hydrocarbon reservoir. In the plane, the area of Hong9 well-Hong72 well-Hong61 well is the favorable area because of the low sand ratio (25%~40%) and the good reservoir quality.