Spectral decomposition characteristics of reef-bank reservoirs of Changxing Formation in Yuanba area, northeastern Sichuan Basin

In Yuanba area of the northeastern Sichuan Basin, the reef-bank in the Permian Changxing Formation is characterized by deep burial depth and great lateral variation, hence is difficult to predict by conventional method. Based on well-seismic calibration and spectral decomposition of short windowed discrete Fourier transform, the frequency range of different facies is figured out. The form and plane distribution of platform margin reef complex changing with frequency are described. The boundary of lithologic reservoir is confirmed, providing scientific guiding for petroleum exploration.