Joint PP-PS litho-elastic AVA inversion: Example from Midland Basin

Compared to PP prestack amplitude versus angle (AVA) inversion, joint PP-PS prestack AVA inversion can provide a more-accurate estimate of VP/VS ratio (or S-impedance) and density, thus enabling a better estimate of lithological classification and petrophysical properties. This is especially important in an unconventional basin such as the Permian where operators are targeting zones with oil-filled porosity that requires hydraulic fracturing to be economically viable. The Texas Midland Basin Wolcampian- and Leonardianaged sediments are the primary targets for oil and gas production and they are both fairly clay-rich. Because hydraulic fracturing rocks with high clay content is challenging, identifying such rocks prior to drilling is of paramount importance for all financial considerations related to field development and production. Single-loop litho-elastic (LE) AVA inversion inverts seismic data to estimate lithology and elastic parameters through data assimilation. Solving jointly for lithology and elastic parameters relaxes the dependency on the prior low-frequency models and has the potential to reduce project turnaround time. Herein, we demonstrate joint PP-PS LE AVA inversion on a three-component, three-dimensional (3C-3D) data set from the Midland Basin.