Inversion of Refraction Data by Wave Field Continuation

Presenter: Roma Widiyansari

Date: 2016/10/20

Abstract

In conventional seismic refraction method, the data is analyzed by picking travel time information and performing a Wiechert-Herglotz integration to produce a velocity-depth profile.  This wave equation continuation method gives alternative approach to refraction inversion to produce velocity-depth models directly from the recorded data without picking travel time. The procedures consist of two linear transformation: a slant stack of the data produces a wave field in the  plane which is then downward continued using  as the imaging condition to retrieve velocity-depth model. The method is iterative because it is necessary to specify a velocity for the continuation. The solution produced by a given iteration is used as the continuation velocity function for the next step. Convergence is reached when the output wave field images the same velocity-depth function as the input to the continuation.  The method is illustrated with several synthetic examples and with a refraction data recorded in the Imperial Valley, California.

Reference

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