Empirical Green function deconvolution of broadband surface waves: rupture directivity of the 1992 Landers, California (M_w = 7.3), earthquake

The paper presents a simple method to determine gross temporal and spatial characteristics of faulting that can uniquely define the fault plane for a relatively large earthquake. The technique involves deconvolution of teleseismic and regional broadband surface waves (and/or body waves) of a small event (an empirical Green function) from the corresponding signals at the same stations for a large mainshock. The procedure is applied to the 28 June 1992 Landers, California (M_w = 7.3), earthquake. The Landers earthquake source duration lasted about 25 sec, and was dominated by two subevents with predominantly north-northwestward rupture extending 60 to 70 km. The subevents show counterclockwise rotations of at least 12° in strike that correlate well with mapped surface rupture. -from Authors