Map of the 2012 Sumatra great earthquake region. The 11 April 2012 mainshock can be decomposed into two subevents separated by about 200 km (green mechanisms and circles labeled I and II). The W phase and Global CMT (GCMT) single-point-source solutions for the mainshock (inset green mechanisms), the W phase solutions for the 10 January foreshock (blue mechanism), for the Mw=8.2 aftershock (yellow mechanism) and for the 5.8 ≤ Mw ≤ 8.2 aftershocks (red mechanisms) are shown. Yellow circles indicate the earthquake epicenters and magnitudes from the National Earthquake Information Center (NEIC) catalog between 1 January 1973 and 10 April 2012. Red circles show the events since the Mw=8.6 11 April 2012 earthquake through May 2012. White arrows indicate the direction of motion of the Australian plate relative to the Indian plate at about 13 mm/yr. |