Caracterización del régimen sísmico y procesos de deformación cortical actual en la esquina noroccidental de Suramérica y zonas aledañas

Abstract

The Chocó Bloc region in the northwestern South American includes the Panamanian and Colombian regions east of the Panama Canal area, to the northwestern Colombia, from the north-western flanks of the western mountain range, above those of the 4 ° latitude north, between latitude coordinates 4 ° N to 8 ° N and longitude 75 ° W to 80 ° W. The block thus formed is under the influence of the subduction zone of the Nazca plate, which collides with the continent with a speed of 58 mm / year, in the WE direction west of the block, it is also influenced by the Caribbean plate that converges against the block at the north end with a speed of 20 mm / year, generating complex tectonic processes that merit investigation. Thus, it is proposed to carry out a study on seismicity and the regional effort regime, characterizing the particularities of the current deformation processes of the earth's crust. This is important because the regional effort regime has managed to produce strong earthquakes throughout the national seismological history that have left considerable material damage and numerous victims; among them events such as November 15, 2004 with a magnitude of 6.7 degrees on the Richter scale and depth 26 km from the surface, with epicenter in the Pacific Ocean 50.5 km southwest of the municipality of Bajo Baudó in Chocó belonging to the block, whose most important damages were observed in Cali for example, the remittance damaged 25 buildings, of which 7 were in very bad condition, and left at least 1,800 victims. In Buenaventura there were 30 houses that collapsed and in Pizarro (Chocó), the number of homes destroyed reached 317 and surrounding areas. Due to the tectonic complexity of the region there is still no clear clarity about the seismogenic sources and seismotectonic processes associated with many of these great events. In this way, the fundamental problem of the present project consists, on the one hand, in the characterization of the regional seismicity and, on the other, establishing the particularities of the stress regime and the characterization of the current cortical deformation processes dominant in the region.