Joint PP-PS Inversion

New information and improved confidence from shear wave data

A flexible joint inversion scheme allows a range of P-wave and S-wave data to be combined for different inversion goals. Analyzing the results from independent datasets can provide additional value and reduce risk or uncertainty. For example, joint PP-PS inversion can help determine fracture density and orientation, provide fluid / lithology discrimination and characterization, enable seismic classification of PP/PS attributes, and identify drilling hazards (over-pressure, shallow gas, rock strength, and others).

Independent poststack inversion can be used as a detailed check of the event correlation or as a deliverable itself. PS data can be inverted directly or after transformation to S reflectivity. For wide-azimuth geometries, the AVO attributes can be analyzed for azimuthal variation. An additional refinement of standard shear-wave splitting inversion can be used to show the direction and degree of tilt in tilted fracture sets.

WesternGeco offers a range of AVO and Inversion technologies appropriate to either conventional P-wave or joint PP-PS data sets.

Related references

• Zou, K., , Dai, J., Hannan, A., Koesoemadinata, A., Xu, H, Yang, S., Shih, C., Zimmermann, J., Multicomponent data interpretation workflow & PP/PS joint inversion: 3D/4C integrated study at Eugene Island Block 330, GOM, SEG Annual Conference, October 2004
• T M. Nickel, B. A. Tjøstheim, G. V. Dahl, F. Ljones, H. G. Borgos, A. Carrillat, L. Sønneland, J. P. Fjellanger, R. Ona, A. Sæbø, AVO inversion of multi-component seismic in anisotropic media, EAGE 65th Conference & Exhibition-Stavanger 2-5 June 2003