The Oil-Gas Possibility Affecting Factors Study In Jurassic And Cretaceous Of Mosuowan Uplift

Mosuowan uplift is located at the central depression of Junggar Basin.It is a long term inheritance basement uplift zone,the ancient uplift formed in the late Carboniferous,in Cainozoic started tilting,the uplift disappeared,and now is a monocline with the structural high part in noth area and the south is lower.The exploration results indicate that the Mosuowan uplift is located in the area of the basin with thicker sediment,and the source-reservoir-cap assemblage is intact,which is a good hydrocarbon accumulation area.The oil and gas are mainly derived from the adjacent hydrocarbon generated sag,which is transferred to the suitable traps through the late Paleozoic and Mesozoic faults.Junggar abdominal area have a total of 5 sets of reservoir stratums,lithology is given priority to with sandstone and glutenite.The discovered oil and gas are mainly distributed in the Jurassic and Cretaceous.The reservoirs has good physical property,and the cores has good capability of oil and gas,but the test result in the actual production is not consistent with the oil capability of the core shows,there is a complicated relationship between the oil-gas possibility of cores and the test results.The article focus on the correlation analysis of main oil reservoirs lithology features,physical properties,oil-gas possibility and the test results of Jurassic and Cretaceous,and compare the oil-gas possibility and test results,combining with the characteristics of tectonic and sedimentary facies to explain the controlling factor of oil-gas capability of reservoirs.As the result,the Jurassic of the wellblock Pen 5 has a certain size sand body and better physical properties,The oil-gas capability of reservoirs has general rules of better physical properties and oil-gas possibility has better test result,and reservoirs with worse physical properties have less oil and gas for their characteristics.Due to the tectonic movement,the oil and gas in some reservoirs migrated to other regions,so these reservoirs have good oil-gas possibility and worse test result.The Jurassic of wellblock Pencan 2 has the similar lithlogy factors of the wellblock Pen 5,a part of reservoirs have worse physical properties,so they have less oil and gas.The distribution of oil and gas has been adjusted by tectonic movement,the residual oil stored in the reservoirs because of the worse migration ability,so the reservoirs have good oil-gas possibility and bad test result.Only a minority has formed some lithologic reservoir with small-scale sand body and bad physical properties,have good test result and physical properties.The Cretaceous of the Mosuowan uplift has a large-scale sand body and better physical properties than the Jurassic,in the process of anaphase adjustment oil and gas moved to other traps because of good connectivity,the residual oil stored in the reservoirs due to bad migration ability,so the test result is worse but the oil-gas possibility is well.Only at the bottom of the well Pencan 2,sedimentary facies shows small sand distribution,the lateral connectivity and ateral occlusion conditions worse than others.The oil and gas can be preserved in lithologic-controlled traps,and become the one that the test result is a oil-water layer in Mosuowan uplift.In conclusion,the differences between the oil-gas possibility and the test results in Jurassic and Cretaceous of Mosuowan uplift are mainly controlled by the physical properties and structural adjustment,and the structural adjustment is the important factor which cause the discrepancy.