| Based on the analysis of petroleum geological conditions of Qaidam Basin, four patterns of oil accumulation in paleouplift around hydrocarbon-rich sag, in paleouplift-paleoslope outside source rocks, in late structure above source rocks and in tight reservoir or lithologic traps are setup. The analogy method and genesis method are used to objectively evaluate the oil resource of different zones, blocks and strata.The results show that the amounts of the conventional oil and tight oil resource are 29.59×108 t and 8.58×108 t respectively. Combining with the current situation of petroleum exploration in the basin, the remaining conventional oil resources and their distribution are clarified. The areas with the most abundant remaining oil resources are located in the western Qaidam Basin. It is pointed out that paleo-uplift of basin margin and slope area, sag-slope zone in basin and large-scale late structural zone in basin are the key exploration fields in the near future. It is also suggested that Shizigou-Dawusi structural zone, Youquanzi-Katmerik structural zone and western segment in front of Altun Mountain are favorable targets for conventional oil exploration, and Yuedong-Zahaquan-Wunan zone, Hongliuquan-Yuejin zone in southwestern Qaidam Basin and Xiaoliangshan-Nanyishan in northwestern Qaidam Basin are favorable targets for tight oil exploration. |
