Today, at 12.24pm UTC (2.34pm in Italy) an intense earthquake magnitude 7.4 (USGS data, 7.7 for INGV), hit the Colombiawith an epicenter located just east of San Jose del Palmarin the Chocó department. The energy released by such a magnitude but the high depth of the hypocenter (about 107 km) allowed some of the energy to be dissipated along the path. Nonetheless, the tremor was clearly felt in several cities in Colombia such as Bogotá, Armenia and Manizales (where a tower of the cathedral collapsed), going as far as Ecuador and Panama.
The very first reports report several buildings collapsed in Cali and Quibdó, with 21 dead and dozens injured. Furthermore, flights have been suspended at various airports in the country. Shortly after the main event, the USGS recorded a magnitude 5.0 aftershock at 98.5 km depth.
From a geological point of view, Colombia is located in a very dynamic area, exactly on the edge of the South American plate. Immediately off its western coast we find another large plate, that of Nazca. A continuous head-on collision occurs between these two giants: the Nazca plate, being denser, immerses and literally slides beneath the South American plate. This process is called subduction. This sliding, however, is not fluid at all: it generates enormous friction between the rocks that fit together, so the tension constantly accumulates until the rock can no longer resist and collapses, releasing all the accumulated energy in the form of seismic waves.
