As the main exploration target in the Fudong slope of the Junggar Basin

the first member of the Upper Jurassic Qigu Formation was investigated.Its lithology

reservoir pore space and physical property were analyzed in lab

and controlling factors of reservoir quality were summarized.Starting from high-quality reservoir analysis

we studied the controlling factors of hydrocarbon accumulation for the Qigu 1 Member based on oil-producing well data

which ultimately enable us to predict hydrocarbon accumulation areas.And the result shows that(1)lithology of the Qigu 1 Member is mainly fine-grained clastic sandstone with high structural maturity and low compositional maturity

and reservoir space is mainly primary intergranular pores

forming a medium porosity reservoir with medium-high permeability;(2)source provenances supply materials for reservoir deposition

while sedimentary facies and palaeogeomorphology control reservoir quality distribution; both compaction and abnormal pressure determine physical properties of reservoirs

while cementation and dissolution have limited impact on reservoir property;(3)the controlling factors of hydrocarbon accumulation are mainly oil and gas migration channels and driven power

with the former involving unconformity and fault development and the latter mainly caused by abnormal pressure difference.In conclusion

we predict four favorable accumulation regions in the Qigu 1 Member of the study area.