DETERMINATION OF THE FAST AND SLOW SHEAR WAVE POLARISATION DIRECTIONS

摘要

A method of determining the polarisation directions of the fast and slow shear waves arising from shear wave splitting due to anisotropy, said directions defining a natural coordinate system, the method comprising the steps of: a) recording at least two components of each shear wave, in a recording coordinate system, b) calculating the value of theta , being the angle of rotation between the natural coordinate system and the recording coordinate system, for which the Lp norm of the rotated traces is minimised if p is less than 2, or maximised if p is greater than 2.