Wavelet transform analysis for lithological characteristics identification in siliciclastic oil fields

• Wavelet transform analysis in well-logs can be used to identify sedimentary facies.
• Wavelet decomposition allows to estimate the depth and thicknesses of rock types.
• Wavelet analysis can be used as first approximation in the characterization of wells.

In this work, we propose the application of the wavelet transform analysis in well-logs (radioactivity, resistivity and sonic) to identify facies. The wavelet transform is applied to a set of well-log data for identifying correlations between wavelet coefficients and lithofacies sequences. Our results indicate that the scales, in a multiscale analysis, are related to the rock thickness and depending on the scale used it is possible to identify other particular or general sequences. The results obtained are compared and corroborated by standard geological procedures for lithological characterization, indicating that the wavelet analysis provides qualitative guides for the identification of lithological properties in wells. All our analyses are based on a siliciclastic oil field that belongs to Chicontepec Formation of the Tampico–Misantla basin in Mexico.