Seismic wavefield polarization - Part I: Describing an elliptical polarized motion, a review of motivations and methods

Abstract

The seismic wavefield can be approximated by a sum of elliptical polarized motions in 3D space, including the extreme linear and circular motions. Each elliptical motion need to be described: The characterization of the ellipse flattening, the orientation of the ellipse, circle or line in the 3D space, and the direction of rotation in case of non-purely linear motion. Numerous fields of study share the need of describing an elliptical motion. A review of advantages and drawbacks of each convention from electromagnetism, astrophysics and focal mechanism is done in order to thereafter define a set of parameters to fully characterize the seismic wavefield polarization.