Advanced 3D Land Internal Mutiple Modeling and Subtraction, a WAZ Oman Case Study

In this Oman land case study we propose a new internal multiple attenuation methodology using a wave equation based multiple modeling technique followed by a 3D adaptive subtraction technique. The first step consists in modeling the multiple wavefield for a variety of multiples generators, for any multiple orders. The modeling is performed in sub-windows selected on the reflectivity series, around the suspected or identified generators. All multiple ray paths for all orders and all periodicities are generated without precise identification of the multiple generators. The generated multiple wavefields are then simultaneously subtracted from the total wavefield using a 3D least square adaptive subtraction technique. Subtraction in the Common Offset vector (COV) domain allows flexibility for testing, production and quality control, as well as optimum efficiency, as each COV volume is subtracted from its multiples content as if it was a stacked volume. It is also a domain that allows efficient data handling for large modern datasets like wide azimuth (WAZ) surveys. The results on complex narrow azimuth and WAZ Oman land datasets are encouraging. The method is accurate, efficient, yet primary wavefield preserving and integrates well in the seismic processing workflow.