Scaling relations of seismic moment and rupture area for outer-rise earthquakes

Abstract A new piece-wise scaling relation for rupture area ( S ) and seismic moment ( M 0 ) was obtained for outer-rise earthquakes using data compiled from previous seismological studies. The compiled source parameters were examined carefully to ensure that rupture area dimensions represent the "actual" rupture area. Twenty sets of S and M 0 pairs for ten earthquakes from independent studies were used for regression analysis. To estimate rupture areas of outer-rise earthquakes whose fault down dip tips, respectively, do and do not reach the oceanic lithosphere base, regression parameter b in S=(M 0 /a) 1/b is 2 with the corresponding regression parameter log 10 a 2 being 1.402 (±0.250), and b is 1.5 with the corresponding regression parameter log 10 a 1 being 6.401 (±0.187). The piece-wise scaling relation developed here can fit outer-rise earthquake data from Mw 7.2 to Mw 8.4 and can be used to estimate rupture areas of earthquakes greater than Mw 8.4.