Geodynamic conditions resulting from the 2010 earthquake and tsunami in the coast of central Chile. The case of Pichilemu Condiciones geodinámicas derivadas del terremoto y tsunami de 2010 en la costa de Chile central. El caso de Pichilemu

Abstract

© 2015, Revista de Geografia Norte Grande, All rights reserved.The earthquake and tsunami of 2010, triggered changes in the geomorphological and sedimentary dynamics along the coast of Pichilemu, in central Chile. These changes were evidenced through the retreat and erosion of sandy beaches and coastal sand dunes. Modification patterns were identified through analysis of satellite images prior to and after the earthquake/tsunami, and compared with records from geomorphological fieldwork carried out in 2004 that measured essential features of representative beach profiles in the headland bay beaches. The variability of beaches dominated by waves was analyzed. The results indicate that there is coastal erosion and a change in the sedimentary balance associated with the subsidence of the coast, and that four years after the earthquake/tsunami, after the erosive phase, a change in tendency towards progradation of sandy coastlines in the headland bay beaches can be observed.