The Virtual Refraction for Noisy Data and Elastic Media
In this work we explain the origin of spurious energy related to refracted waves, but more importantly, we use this spurious event - which we call the virtual refraction - to quantify subsurface parameters (i.e., wave speeds and depth to interface). Using numerical examples we show the cause of this spurious wave. We illustrate its use in a numerical two-layer refraction experiment, providing an alternative approach to conventional intercept-time seismic refraction analysis (Palmer, 1986). Finally, we discuss possible advantages of this technique to conventional refraction methods; particularly, the ease of picking the virtual refraction velocity (even in the presence of noise) and its self-contained nature to invert for the subsurface parameters.
van Wijk, Kasper; Mikesell, T. Dylan; and Calvert, Alexander. (2009). "The Virtual Refraction for Noisy Data and Elastic Media". 71st European Association of Geoscientists and Engineers Conference and Exhibition 2009, 1, 2222-2226.