Pre-stack Depth Migration (PSDM) Using Tomography Based Velocity Model

Nowadays, the requirements for obtaining high resolution seismic sections lead to searching different approaches to processing and interpretation of the data. Creating depth sections by Pre-Stack Depth Migration (PSDM) is a key issue for obtaining more reliable and informative seismic sections, which in turn enable more confident and more reliable interpretation of seismic data. Depth imaging of seismic data is used to map the complex subsurface geology in areas that have steeply dipping structures, faults or in any areas with a rapidly changing geological environment. The main aspect for achieving high quality depth imaging is the ability to build detailed and accurate velocity model. The model building process involves making an initial estimate of interval velocities for each layer in the model, followed by iterative refinement of the model velocities and layer thicknesses until residual moveout has been minimized on depth migrated gathers. Accurate velocity estimation and depth imaging provides the key to understanding the subsurface.