Abstract: | This article reviews the development of the study of the focal mechanism of earthquakes. The representation of focus by point and finite sources are reviewed. The use of initial motion and spectral amplitude of P-waves, the polarization of S-waves and the application of numerical methods in determining optimum solutions are discussed. A survey of the recent advances in the application of surface waves, free oscillations and static dislocations for the determination of focal mechanisms is given. A brief outline of the major results of the interpretation of the focal mechanism solution of earthquakes in terms of regional stress distributions and the geodynamic processes that are currently taking place is also included. |