Foothills land data imaging with reverse time migration in angle domain

Reverse time migration (RTM) technology provide a powerful tool for subsurface complex structure imaging. In the past few years, we have developed GPU based RTM and RTM angle gather technology for acoustic isotropic and anisotropic media, including VTI, HTI, TTI, orthorhombic and tilted orthorhombic media. With the efficient algorithm implemented based on an optimized Laplacian optical flow, RTM angle gathers is suitable for processing large 3D dataset. RTM angle gathers make it possible for geophysicist to take fully advantage of seismic information for subsurface complex structure imaging, velocity model building, and seismic attribute analysis for reservoir study. For the land seismic data with foothills, the imaging processing is a big challenge due to the complicated wave phenomena can't being processed with simple assumption based imaging methods. As the most accurate imaging method up to now, Reverse time migration with angle gather could be the best tool to handle the imaging for land data with foothills. In this paper, based on the elastic foothill model with strong velocity contrast and topography from SEG Advanced Modeling (SEAM) Project, a synthetic elastic seismic dataset is generated to investigate RTM and RTM angle gather capabilities in handling the image of foothill geological area. Numerical examples and field data examples demonstrate that our RTM technology is capable of yielding accurate imaging for complicated near-surface condition and complex subsurface structure, and RTM angle gather can further improve the image quality.