Abstract
To estimate appropriate source modelsof small earthquakes or eventsprior to the operation of the modernstrong motion networks, waveform inversions using near-field strong motion records at only one or two stations can be effective method. Based on my recent study results of the one- or two-station waveform inversion for the 1990 Odawara earthquake (MJ5.1), I discussed the following two topics: (1) the reason why the strike shows the tradeoffs withthe rakein low-dip nodal plane by means ofdecomposing the SV-wave radiationpatternfrom a double-couple point source into the contributions from single-couple sources on two nodal planes, and (2) the effect of different velocity structures to the source parameters.
