Fig. 4: Rupture front propagation speed vs along-strike distance and aftershock production.

a Rupture velocity as a function of the distance from the epicenter (squares) normalized to the S-wave velocity in the areas at shallow depths (3.6 km/s⁴⁴). Y error bars display the uncertainty of the rupture velocity (shown in Fig. 3) normalized to the S-wave velocity; x error bars show the standard deviation of the along-strike distances between the two radiating points used for the calculation of the velocity. The red line and black dotted line display, respectively, the cumulative slip and the slip rate averaged over the first 25 s of the rupture. The magenta triangles mark the subsegment of the Pazarcık fault (PAZ-SUB) where sequences and M2.5+ earthquakes nucleate, as indicated in⁴. The green triangles mark the conjunction of the Narli fault with the EAF. The two black triangles show the position of the Gölbaşi basin. b Location of the aftershocks during the first 11 days after the mainshock; c as (b), but for the earthquakes occurring in March–May 2023. The red line shows the density of the seismicity along the strike. A minimum in the seismicity density appears at distances from the epicenter broadly ranging between 45 km and 70 km.