Global Earthquakes

Abstract

The information on the Earth seismicity in 2013 at the level of strong earthquakes with M≥6 is provided according to the Seismological Bulletin of the Geophysical Survey of RAS (GS RAS). The initial Seismo-logical Bulletin for 2013 contains parameters of 4212 earthquakes in the world, versus 4845 in 2012. This article analyzes parameters of 160 strong earthquakes of the Earth in 2013 with M≥6, including 24 strongest earthquakes with M≥7 and the maximum earthquake of the Earth with Mw8.3 occurred in Okhotsk Sea, as well as four earthquakes with M6.0–6.8, which resulted in significant sacrifices and destructions. The location of earthquake epicenters and seismic stations, whose data were used to deter-mine the main parameters of earthquake foci, are shown, as well as a comparative analysis of the number of earthquakes and seismic energy released within the Earth's seismic regions is given. The information on focal mechanisms and consequences of 28 strongest earthquakes, including macroseismic effect, number of victims, landslides, tsunamis, etc. is given. The epicenters of most of them are confined to the boundaries of the largest tectonic plates of the Earth, and their focal mechanisms correspond to the basic laws of plate movement. The hypocenters of most of the strongest earthquakes are located within the Earth's crust, with the exception of earthquakes in Colombia, the Kuril Islands and south of the Fiji Is-lands, which had intermediate depths (h=98–171 km), and the strongest in 2013 Okhotsk earthquake, the source of which lay in the upper mantle at the depth of h=617 km. The movement in the source of the Okhotsk earthquake corresponds to the subduction process of the Pacific plate under the continent and indicates that the subducted plate is at the depth of 617 km.