Fig. 2.
Space-time plots of seismicity in the area between the foreshock and the mainshock. (a) Red and green open circles denote earthquake events plotted as functions of the elapsed time and the distance from the mainshock epicenter along the cross-sections A−A′ and B−B′, respectively (see Fig. 1(a)). Stars indicate hypocenters of the foreshock and the mainshock. Specification of fitting curves and line are indicated in the panel. (b) Black circles denote events taken from (a) to define the migration front and used for the least-squares analysis. Gray parabolic curves and lines show the resulting least-squares solutions specified in the inset; thick and thin curves are those from Lm = 37 and Lm = 32.