Tomography and Velocity Modelling

Velocity model building

The goal of velocity model building is to derive the best possible velocity models from available data. Model building is therefore a key step of PSDM workflows. Spectrum has a variety of techniques and tools to build and validate complex 2D and 3D isotropic and anisotropic velocity models.

For velocity inversion we use reflection-based tomography workflows with conventional “top-to-bottom” iterative updates approach based on gather flatness (residual moveout). Spectrum uses grid-based and horizon-based tomography solutions depending on model complexity and data quality.

Geological interpretation, wells and other non-seismic information are used during all stages of PSDM workflow as part of robust and more complete solution.

Vel-Modl-Stack-B4
Vel-Modl-Stack-Aft


Kirchhoff PSDM image gathers before/after tomography

Vel-Modl-Gathers-B4
Vel-Modl-Gathers-Aft


Kirchhoff PSDM image stack before/after tomography