Study On Structural And Volcanic Reservoir Characteristics Of Kong Member 3 In Weibei Sag

Guided by the theories of Structural Geology and Reservoir Geology, and using drilling, seismic, logging and regional geological data, the strata were correlated and divided and the seismic data was interpreted, and then the structural characteristics of Kong Member 3 in Weibei sag were studied. On terms of the analyses of rock characteristics, eruption period, the development law of volcanic rock, the reservoir type and control factors of volcanic rock reservoir were studied. So it is necessary to recognize accumulation conditions and enrichment characteristics of oil and gas and prediction of favorable zones of volcanic reservoirs.Based on the Weibei 3D and WaCity 3D seismic, the work was done, T9 2×2 fine seismic interpretation(equivalent the top of Kong Member 3), the multi well T9 horizon of time depth calibration, making relatively accurate velocity field, rendering the T9 structure diagram. According to the T9 structure diagram of Weibei sag, the structural division is distinct, it can be roughly divided into four tectonic zone. For northern sub-sag belt, buried depth is larger, less fault development, fault for north-west direction. Eastern for Zaohu fault nose belt, the main fault near east-west direction is given priority to, fault extension length, fault displacement is larger, and the nearly ns-trending adjustment fault is development, also fault is small, regulating role. For the Wacity fault terrace zone in the west and fault extension distance is long, west to the north of the main direction of fault is given priority to. Fault development is not obvious in the southern slope belt.According to the field, core, seismic data, volcanic facies of Weibei sag are divided, volcanic facies mainly include volcano channel facies, overflow facies and the volcano erupted sedimentary facies. According to the core observation, microscopic identification, the rock types of Kong Member 3 in Weibei sag include basalt, basaltic andesite, volcanic clastic rock etc. Using the well seismic analysis technology, the strata were correlated and divided, the period of volcano rock was studied. By volcanic cyclicity division of Chang 36 well, three there are at least 13 period volcanic eruptions. According to core observation and slice analysis, the volcanic rock reservoir space types of Kong Member 3 Strata in Weibei sag mainly include air voids and fissures. According to core physical property test data, variation range is larger, volcanic rock reservoir of Weibei sag belongs to the high porosity of low permeability reservoir. Finally, the favorable reservoir is forecasted.