3D Simultaneous Joint PP-PS AVO Seismic Inversion in Schiehallion Field, UKCS

A workflow for the simultaneous joint PP-PS AVO inversion of seismic data from the Schiehallion field (UKCS) is discussed. First a process to address the main challenge of getting reasonable PS to PP data registration, before any prestack inversion, is presented. Then the comparison of the estimated elastic properties from poststack and AVO inversion approaches showed the benefits of including PS along with PP AVO seismic data in a joint inversion process. The acoustic impedance quality estimated from the PP poststack, the PP AVO and the joint PP-PS AVO inversions was equivalent. However the joint PP-PS AVO inversion, compared with the PP AVO inversion, gave improved shear-related property estimation and proved that the density estimation was feasible and with an overall good quality. This inversion study confirmes that acquiring PS data in addition to PP data is justified where density is a good reservoir discriminator, as long as the PP and PS datasets are carefully processed and registered.