Simulating migrated seismic data by filtering an earth model: A implementation

Abstract

An earth model is used in a collaborative environment in which some members provide information for its construction and others utilize the result. Validating an earth model by simulating a migration image is an important step. However, the high computational cost of generating 3D synthetic data, followed by the process of migration, limits the number of scenarios that can be validated. To overcome this computational cost, a novel strategy is used where a migration image is simulated by filtering a model with a spatial resolution filter. One of the key properties of this approach is that the model that describes a target-zone is decoupled from the macro-velocity model that is used to compute the spatial resolution filters. Consequently, different models can be filtered with the same resolution filter. For a horizontally layered medium, the Gazdag phase-shift operators are used to construct a common-offset spatial resolution filter to simulate the phase of 2D primary reflection data. To approximate a spatial resolution filter in a laterally variant medium, ray trace information is used as an illumination constraint. Additionally, the influence of seismic uncertainties on the shape of a spatial resolution filter and the resulting migration image are simulated. These filters enhance an iterative earth modeling approach.