Controlling factors of the oil reservoirs from the Jurassic Fuxian Formation in the Huaqing region, Ordos Basin

In the petroleum exploration and development of the Ordos Basin, the Jurassic strata are interpreted as the major target strata, in which the oil reservoirs from the Jurassic Fuxian Formation in the Huaqing region are delineated as more promising areas for petroleum exploration. The present paper gives a detailed description of the pre-Jurassic palaeogeomorphological features and the enrichment and controlling factors of the oil reservoirs from the Jurassic Fuxian Formation. The oil reservoirs in the Fuxian Formation are believed to be derived from the excellent source rocks in the underlying Triassic Yanchang Formation, and consist of the structural-and lithological-structural oil pools developed in the point bar deposits on the slope zones and controlled by the pre-Jurassic palaeogeomorphological features. The factors favourable for the enrichment of oil reservoirs include sufficient hydrocarbon supply, point bar deposits, migration conduits, nose structures and cap rocks.