Regional di erence in scaling laws for large earthquakesand its tectonic

For large earthquakes occurred at and around plate boundaries, we examined relations between seismic moment M 0 , fault length L, fault width W and average fault slip D, and found the following scaling laws. For interplate strike-slip events, the well-known L-cubed dependence of seismic moment M 0 breaks when L exceeds 30 km, and D and M 0 increase with L as D = L==(L+) and M 0 = WL 2 =(L +), respectively, with W is 15 km and the average stress drop is 1.4 MPa. For intraplate strike-slip events we obtained the same relations, except for much higher stress drop (4.6 MPa). For underthrust events at island-arc subduction zones we found also the saturation of fault width (W 100 km) and the breakaway from the L-cubed dependence of M 0 for the events larger than L = 200 km.