A turning-ray algorithm using Slotnick's equation
Babatunde Arenrin, Gary F. Margrave, John C. Bancroft
Turning-ray tomography is a good tool for estimating near surface velocity structure, especially in areas where conventional refraction statics fail such as in the case of a hidden layer. In a previous paper (Arenrin et al, 2014), we already demonstrated this by applying a tomostatics solution to Hussar 2D seismic line using Landmark's PROMAX software. In this paper we have developed a turning-ray tracing algorithm that uses Slotnick's equation. The algorithm traces turning-rays through a linear velocity v(z) medium, and has the option of specifying the top layer velocity, takeoff angles, and the subsurface velocity gradient. However not in its final product, the turning-ray traveltimes from the algorithm are in agreement with the traveltimes generated using an acoustic finite difference scheme.