Junggar Basin is a large transpressional superimposed basin experienced multi-stage tectonic movements. Its hydrocarbon accumulation process and reservoirs distribution are complex. By using the new theories and methods of fluid history analysis of petroliferous basins,we comprehensively studied the evolution characteristics of chemistry pressure and hydrodynamic fields as well as their effects on petroleum accumulation and distribution in Junggar Basin, revealed the control of hydrodynamics on hydrocarbon generation, migration and accumulation as well as oil-gas-water contact,and identified favorable areas for hydrocarbon exploration. The sealing conditions are poor nearby the northwestern margin of Junggar Basin where desalination occurs due to meteoric water percolate in a downwards direction. Small oil/gas pools may exist in local litholgoic traps or stratigraphic traps in Mahu sag and Pen-1 west sag where desalination occurs due to water discharging from shale compaction. Large oil/gas fields may exist in the northwestern fault-terrace belt, Luhang uplift,Mosuowan-Mobei uplift,Da-basong uplift and Cheguai area where drainage occurs through leakage and leakage-evaporation.%准噶尔盆地为大型压扭性叠合盆地,经历了多期构造运动,成藏过程及油气分布规律十分复杂.运用含油气沉积盆地流体历史分析的新理论、新方法,从动态和演化的角度,综合研究准噶尔盆地地层流体化学场、压力场、流体动力场的形成演化特征及其对油气成藏、分布的影响,深入揭示盆地流体动力学过程对油气生成、运移、聚集和油、气、水分布规律的控制作用,并预测有利油气勘探区.结果表明,盆地西北缘的边缘地带是大气水下渗淡化区,通常遭受大气水下渗淋滤破坏,油气保存条件较差；玛湖凹陷、盆1井西凹陷内部为泥岩压实排水淡化区,油气可能在局部岩性、地层圈闭中聚集成藏,油藏规模相对较小；西北缘断阶带、陆梁隆起区、莫索湾-莫北凸起、达巴松凸起和车拐地区等为越流、越流-蒸发泄水区,油气大量聚集,是大型油气田形成的重要场所.
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