摘要
///The Tazhong area is the main exploration and petroleum-rich area of Tarim Basin. Lianglitage Formation of Ordovician was controlled by Tazhong No.I slope-break zone, and developed shelf margin reef-shoal reservoir with the character of low porosity to ultra-low porosity and low permeability, which the buried depth was between 4 500 to 6 500 m. By the analysis of accumulation process, it’s confined there were three main accumulation periods in Tazhong area, the first accumulation period was Late Caledonian. The second accumulation period was Late Hercynian. The third accumulation period was Late Himalayan. During Late Himalayan period, the crude-oil-cracking gas which generated from Cambrian reservoir accumulated in shallow Ordovician along the deep fault, transformed the oil reservoirs into condensate gas reservoirs with large-scale distribution.