Research on facies and reservoir seismic description methods of volcanic oil and gas reservoirs in Zhongguai area

In recent years, significant breakthroughs have been achieved in the exploration of deep volcanic rocks in the Junggar Basin, highlighting their substantial exploration potential. The complex distribution of volcanic reservoirs is attributed to the multi-phase tectonic evolution within the basin, with their superior reservoir properties playing a crucial role in natural gas formation. However, due to the combined effects of multi-cyclic volcanic eruptions and tectonic activities, predicting volcanic facies distribution and favorable reservoirs remains highly challenging. This study focuses on the third member of the Jiamuhe Formation in the Zhongguai Uplift. By integrating drilling and petrophysical data with well-seismic analysis techniques, a seismic identification model for volcanic reservoirs has been established. The findings reveal that different facies exhibit distinct seismic response characteristics. Andesite, rhyolite, volcanic breccia, and volcanic clastic rocks show variability in amplitude, frequency, and continuity. Using structural-guided filtering, high-resolution coherence analysis, and 3D body carving techniques, the locations of volcanic craters and eruption centers were successfully identified, further clarifying the distribution patterns of volcanic facies. By combining multi-attribute clustering analysis and seismic attribute extraction, a volcanic facies zone distribution map was generated, and favorable exploration directions for volcanic reservoirs were proposed. The study provides technical guidance for the exploration of deep volcanic oil and gas reservoirs in the Junggar Basin and holds significant application value.