Azimuthal Processing For Unconventional Resource Plays Using An Orthorhombic Velocity Model
نویسنده
چکیده
Oil and gas production from tight, fractured reservoirs (sandstone, carbonates and shale) has increased significantly over the last decade. These hard rock targets are often characterized by vertically aligned fractures (i.e. HTI) embedded in a layered sequence (i.e. VTI). In this geologic setting, seismic velocities and η can vary with azimuth and depth. This is orthorhombic anisotropy and can be described by an orthorhombic velocity model with VTI and HTI velocity models being special cases. In this paper, we present a method and workflows to take orthorhombic anisotropy into account in seismic time imaging. Synthetic data and real data from unconventional resource plays demonstrate that the proposed method and workflows can produce sharper images, better preserve AVO/AVAZ integrity and increase incident angle available for AVO/AVAZ analysis.
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