Study on three independent parameters of focal mechanism solution

摘要

In this paper,the relationships of the plunges and azimuths of T and P axes versus the strikes,dips,and rakes of two seismic nodal planes were derived to provide reference for earthquake researchers.The independence of the plunges and azimuths of T,B,and P axes in focal mechanism solution was discussed,and it was concluded that three parameters,i.e.,the azimuths of T,B and P axes,are completely independent.The focal mechanism solution representation based on Euler rotation was introduced,using three Euler angles in place of the plunges and azimuths of T,B,and P axes,and three focal mechanism solution representations were briefly compared and analyzed in respect of accuracy on the basis of the assumption of rounding;it was concluded that the Euler angle representation has better accuracy,compared with the azimuth representation and the traditional representation with T,B,and P axes.