Earthquake in Chile -- a complicated fracture
The extremely strong earthquake in Chile on 27 February this year was a complicated rupture process, as scientists from the GFZ German Research Centre for Geosciences found out. Quakes with such magnitude virtually penetrate the entire Earth's crust. After closer analysis of the seismic waves radiated by this earthquake during the first 134 seconds after start of the rupture, the researchers came to the conclusion that only the region around the actual epicentre was active during the first minutes. In the second minute the active zone moved north towards Santiago. After that the region south of Concepción became active for a short time. This rupturing trend agrees well with the distribution of the aftershocks during the following three days, as observed by the GEOFON-measuring network of the GFZ up to 03.03.2010.