Staggered source acquisition to improve image’s fidelity

To image complex subsurface structures, the wavefield recording layout is more suitable than the conventional method of seismic data acquisition layout since it is better to attenuate noise and to record more energy that impacts subtle aspects of the geologic objective. However the wavefield recording layout increases acquisition costs significantly and also leads to challenges for subsequent data processing. Although the costs for receivers have been reduced remarkably as the acquisition technology has been improved for land seismic exploration, but the costs for sources haven’t changed much. We propose a cost effective wavefield recording acquisition layout: staggered sources for 3D land seismic data acquisition to improve complex subsurface structures image without increasing acquisition cost. The layout of staggered sources divides one shot line in conventional layout into multi-sub-shot lines. The subshot lines are equally staggered along the shooting direction within rolling interval between two adjacent templates which leads to smaller distance between shot lines with same total number of shots for a survey. The proposed layout has been applied on a synthetic 3D model derived from a field 3D survey. In this case study, one shot line with 6-shots in the conventional layout is divided into 3 staggered sub-shot lines with 2 shots for each sub-shot line. To examine the effectiveness of this layout, the forward modeling is used to generate 3D synthetic seismic shot gathers for both conventional and staggered source layouts. Illumination analysis, prestack reverse time migration, and turning ray tomography are performed respectively. The results show that the staggered sources acquisition layout provides stronger illumination, higher fidelity subsurface image, and more reliable near surface models than the conventional source acquisition layout without increasing the acquisition cost.