The gas reservoir, which is located in the Anda-Wangjiatun area of the Xujiaweizi fault depression in north of Songliao basin, is one of the huge volcanic reservoirs in deep layer. The reservoir displays a series of characteristics, such as complicated lithology and lithofacies, strong heterogeneity, complicated seismic response and so on. The favorable gas-bearing reservoir prediction is much more difficult. With use of time-frequency analysis technique, which is based on wavelet change, combined with the high and low frequency information in seismic data, the gas-bearing property prediction has been carried out in the volcanic reservoirs of Yingcheng formation, which developed in Anda-Wangjiatun area. Through comparison and analysis of all kinds of geophysical parameters’ response to volcanic reservoir which are rich in natural gas, it indicates that these parameters, such as attenuation gradient, energy percentage, specified the ratio of energy to the corresponding frequency and show a better result. The gas-bearing prediction result in this area is consistent with that of wells. The coincidence rate even reaches to 75%. Three favorable gas-bearing areas have been pointed out, which provides a basis for volcanic gas reservoir exploration.
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