Relation of Sequence Stratigraphy and Oil-Gas Accumulation of the Jurassic in the Northern Shaanxi Province
Guided by the principles of modern sedimentology and sequence stratigraphy and based on comprehensively analysis of depositional environment indicators, outcrop sections, lithologies, well logs, seismic and paleontological data, the Jurassic in the southeastern of Ordos Basin is divided into six third order sedimentary sequences separated by recognizable sequence boundaries. The characteristics of sedimentary cycles and evolution of systems tract, as well as the implications for source rock and reservoir development, are discussed. The main reservoirs locate the first long time cycle LSC2 of Yan’an Formation base. They are channel subfacies sandstone of transgressive systematic range.