The southern Zhongguai Rise has gained wide attentions due to its commercial hydrocarbon discoveries from volcanic deposits in Jinlong Oilfield. An integrated analysis of geologic and geophysical data assists in determination and depiction of volcanic lithology and volcanic facie, characterization of volcanic reservoirs, and discussion of constrains on volcanic lithology and lithofacies. The conclusions suggest that two types of volcanic lithology, including volcaniclastic rocks and silicic molten lava, can be identified based on cores. In addition, two types of volcanic lithofacies can be delineated according to cores and wireline responses. Whereas explosive facies are mainly developed in the early depositional period, the effusive facies are developed through the depositional period. Furthermore, the reservoir space predominantly consists of pores and fractures according to thin sections. The physical property varies with time; that is, the porosity distribution varies slightly. In contrast, permeability distribution varies significantly. The volcanic reservoirs can be generally attributed to high-porosity and low-permeability reservoirs in volcaniclastic rocks or silicic molten lava. The volcanic lithofacies, facies distribution, diagenism, and paleogeomorphology exert controls on physical property and reservoir performance of volcanic reservoirs together.

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