Gulf of Suez acquisition design using 2D and 3D full wave equation simulation

The operational condition that dominates the survey planning and implementation is the presence of major shipping transit fairway to and from the Suez Canal. This shipping thoroughfare covers about 70% of the survey area. Operational considerations necessitate a shooting orientation that closely parallels the shipping lanes, which approximates the strike direction of the subsurface target. Shooting in the dip direction, across the shipping lanes, was not considered to be operationally feasible for a 3D spread or operation. A 3D seismic acquisition program took place in the northern Gulf of Suez, Egypt during early 2003 (figure 1). The marine towed streamer survey was preceded by an acquisition feasibility, design and modeling study that used a variety of techniques. The primary goal of the 3D survey design work was to specify and assess a set of key acquisition parameters that could be implemented in the field which, critically, had to support the successful implementation of modern demultiple, noise attenuation and 3D image processing techniques and technology. It was important to look for a solution that integrated operational realities and specific processing requirements. Previous 2D seismic acquisition programs in the area have utilized a limited offset streamer, presumably to accommodate dip and strike shooting through the shipping lanes. The 2D results typically suffer from marginal to very poor demultiple results and very poor imaging of the target structures. It was estimated that poor results were probably due to a combination of high residual noise levels related to limited demultiple technology and 2D imaging limitations. Exploration drilling results, based at least partially on the 2D datasets, have been disappointing to date. As a primary design tool on this project, we used 2D and 3D wave equation simulation. The aim of the wave equation simulation was to generate realistic synthetic seismograms that could be used to assess the effect of different field design parameters on exploration objectives. The goal was to design an economic and operationally feasible 3D survey that met the exploration objectives of our staff. This presentation will demonstrate how the wavefield simulation work was utilized and found to be useful for 3D seismic survey planning. Wave equation simulation was used in preparation of the acquisition program specifications. The technique was utilized to produce synthetic seismogram shot records that were in turn examined, interpreted and processed to assess the impact of various parameter combinations on meeting technical, operational and economic requirements set by the exploration staff. Introduction