Citation/Abstract

An algorithm for full waveform inversion involving two programs by different researchers is implemented to compute Green's functions and to use these Green's functions to invert observed seismograms for the seismic moment tensor of local earthquakes. The inversion method for local earthquakes is first tested on California earthquakes, and good fits between synthetic and observed seismograms suggest that the moment tensors are well resolved. The same method is applied to local earthquakes in Northeastern North America (magnitudes from 3 to 5). For earthquakes of magnitude 4.0 and greater in Northeastern North America, reliable results can probably be obtained for most earthquakes, with the fault planes being close to those from the first motion focal mechanism. For smaller earthquakes (M<4.0), the inversion results become less reliable with decreasing magnitude.