Evaluation of Different Interbed Multiple Attenuation Techniques, a Case Study from Kuwait

By

Adel El-Emam¹, Abdulatif Mohamed¹, Will Gowans²

(1) Kuwait Oil Company (KSC), Ahmadi, Kuwait (2) WesternGeco, Salmiya, Kuwait

 Seismic data from the State of Kuwait is typically contaminated with multiple energy, particularly interbed, that is resistant to conventional data processing attenuation techniques. Multiples impact the accuracy of structural and stratigraphic mapping and the reliability of seismic attribute measurements. The Geophysics Team of Kuwait Oil Company (KSC), Exploration Group, has implemented a program to test and evaluate seismic data processing multiple attenuation techniques during its major re-processing projects targeted at both exploration and field development objectives.

Surface and interbed multiples frequently do not exhibit significant velocity discrimination and are too complex in nature for statistical methods such as deconvolution to be effective, especially if true amplitudes are to be preserved. Conventional techniques based on both velocity discrimination and deconvolution have been ineffective in attenuating multiples in the deep Jurassic to Permian formations from onshore 3D seismic data from Kuwait.

This case study will present the different techniques applied and focus on the latest results achieved using an advanced wave equation consistent modeling and adaptive subtraction approach that has been successfully applied for the first time to onshore 3D data. The presentation will review the extensive test work that has been performed to identify the key multiple generating horizons through integrating the skills of the interpretation and processing geophysicists with available VSP and synthetic data.