The authors use the wavelet decomposition technology to resolve the conventional seismic data track into a collection of different frequency wavelets, and then check the gas-bearing reservoirs based on the spectrum anomaly detection. The Shaximiao sequence as an objective layer of CC area is a set of river-delta deposits with a single-storey sandstone thickness about 20 m. The reservoirs in the similar river in the different locations and the similar position in the different rivers have the different gas concentration. The traditional spectrum technology of seismic data is restrained by the window restriction so that the anti-noise and poor stability cannot accurately identify the gas-bearing.