准噶尔盆地西北缘掩伏带构造特征及勘探潜力分析

Structure Characterization and Exploration Potential Analysis of the Shielding Belt in the Northwestern Rim of Junggar Basin

前陆盆地掩伏带是准噶尔盆地西北缘油气勘探的重要领域。针对掩伏带构造特征及成藏富集规律不清的问题,运用构造解析、油气地球化学等研究方法,通过构造演化、成藏期次分析手段,明确了西北缘掩伏带构造及演化特征、成藏模式。研究结果表明,西北缘构造具有东西分带、上下分层的特点,掩伏带地层分布与后期逆冲推覆构造是油气成藏的主控因素;构造型掩伏带的源-储-盖层分布对于形成高效疏导体系和大规模地层油气藏十分有利。该研究推动了风险探井的部署实施,为该地区的勘探提供理论支撑。

The shielding belt of foreland basin is considered as a major area for hydrocarbon exploration in the north- western rim of the Junggar Basin. Structural analysis and hydrocarben geochemistry are used to charaeterize the structures and hydrocarbon accumulation patterns in the shielding belt. The shielding belt structures and evolutions in the northwestern rim are clarified by tectonic evolution and hydrocarbon accumulation period analysis. Research indicates that the structure in the northwestern rim is featured by east-west zoning and top-bottom lamination. The strata distribution of shielding belt and the later thrust nappe structure are the main-controlling factors for hydrocar- bon accumulation. The source-reservoir-caprock distribution in the tectonic shielding belt is very favorable to the development of high-efficiency transmission system and large-scale stratigraphic reservoir. This research promotes the deployment of risk exploration wells and could provide certain theoretical reference for the hydrocarbon explora- tion in this region.