THE CONDITION AND PATTERN OF RESERVOIR FORMATION AT LUXI AREA IN JUNGGAR BASIN

The condition and pattern of reservoir formation at Luxi area are studied in this paper.On the basis of the study,it is pointed out that the condition of reservoir formation is favorate.The source rock is mainly the Fengcheng Formatiom of Mahu trough at Mabei and Madong Xiayan area,and the lower Wuerhe and Fengcheng Formatiom of West trough of Pen well 1 of Shixi and Shinan oil field in Luzhong area.The reservoir condition is good,and the reservoir condition in Xiayan area is better than that in Madong area.The main trap is unconformity and lithological trap.The trap formed in Permian period and the oil or gas migrated and accumulated in middle,last Triassic period,Jurassic period and Cretaceous period.The main transporting passage of oil and gas is faults and the permeabale layer and unconformity surface.The migration of oil and gas at top boundary unconformity of all strata of the Permian system and the Triassic system exists only on the slope in Luxi area.The migration of oil and gas at top boundary unconformity of Xishanyao Formation and Jurassic system exist mostly in the uplift of Luxi area.There are two kinds reservoir patterns including side of source-unconformity-slope-zone type and outside source-unconformity-fault control-steps type in Luxi area.Finally the favorable objects of reservoir in the strata related with unconformity include the slope area in Luxi area,the jointing area of Sangequan Oilfield and Shinan Oilfield,and the southern member of Sannan Depression in Junggar Basin.