Journal of Geophysical Research, B, Solid Earth and Planets 94(3): 2857-2873
1989
Southeastern U.S. recurrence relations are developed for the region and for various subregions (three geologic provinces; four seismic zones) from a combination of historical (1698-1977) and network (1978-1986) earthquake catalogs. The synthesis of these two data sets was accomplished by the application of MM intensity to m (sub b) (L) (sub g) ) conversions in the form of discrete distributions to the historical catalog. Aftershocks were removed from the resulting catalog, it was tested for completeness, and then a maximum likelihood curve fitting technique for unequal periods of observation was employed. Tests were also made for different size magnitude intervals and different maximum and minimum magnitudes to assess the stability of the various data sets.--Modified journal abstract.