This paper makes systematic analysis of geological factors of natural gas accumulation in Denglouku formation of Gulong-Changjiaweizi region, including reservoir characteristics, gas source condition, source-reservoir relationship, structural condition, etc. It turned out that K1d2 in Gulong-Changjiaweizi region is generally typical tight sandstone reservoir with low porosity and permeability due to the poor physical properties. The gas source rock of K1d2 formation has larger gas producing capacity.The relationship between source rock and reservoir shows as interbed interfinger or directly contiguity contact, which is beneficial for large-area gas accumulation. The gas generation area of source rock in this region is always in the center and slow downdip direction of Gulong depression with a smaller dip angle on the adjacent tight sandstone reservoir, where faults are rare. The result of comprehensive analysis shows that K1d2 formation in Nothern Songliao Basin and its neighboring layers could be considered as a favorable target of the tight gas reservoir study in Northern Songliao Basin due to its favorable geological conditions of deep basin tight gas reservoir generation, such as tight reservoir, sufficient gas source, communicating source-reservoir relationship and constant flattened structure.
Controlling effect of fractures on gas accumulation and production within the tight sandstone: A case study on the Jurassic Dibei gas reservoir in the eastern part of the Kuqa foreland basin, China
