Application of the Wavelet Transform and INPEFA in Sequence Stratigraphy

[Image: see text] The strata of the Shan 2 Member of the Shanxi Formation of Permian(S2)in the LQ Gas Field in the northeast of the Ordos Basin restrict the study of sand body distribution and lateral distribution. The accuracy of sand body prediction is reduced, which greatly affects the exploration and development of oil and gas. In order to accurately characterize the transverse distribution of sand bodies and improve the prediction accuracy of sand bodies, S2 is divided by the sequence stratigraphy method. Research based on the traditional stratigraphic division method includes seismic, logging, and core data. The logging curve is processed by INPEFA and the wavelet transform to reduce artificial division interference. The range of the S2 section is limited by the seismic interpretation surface. The maximum entropy spectral analysis and the wavelet transform are used for fine division, and S2 is divided into 1 long-term base level cycle, 6 medium-term base level cycles, and 11 short-term base level cycles. The fine stratigraphic division improves the exploration accuracy of oil and gas reservoirs.