Resumen de Cenozoic geomorphic and tectonic development of the Patagonian Andes (42°S to 52°S): a regional investigation using fission-track thermochronology
Fission-track (FT) analysis has been applied to assess the Cenozoic geomorphic and tectonic evolution of the Patagonian Andes in response to subduction of an active oceanic spreading centre and activity along the major transpressional intra-arc Liquihe-Ofqui fault (LOF) system. Away from the LOF results indicate increased cooling and denudation in the upper plate to subduction coeval with an increase in plate convergence rates. Later spreading centre subduction causes a slow down in cooling and denudation in the upper plate.
A significant west to east decrease in total denudation across the Patagonian Andes refects the influence of orographic ally enhanced precipitation and erosion on the west side of the Patagonian Andes facing the prevailing weather. The LOF marks a region of significant, but localised accelerated post mid-Miocene cooling and denudation. Local transpression induced rock uplift along the LOF is proposed to have acted to focus glacial erosion and hence denudation on this part of the Patagonian Andes since the latest Miocene.
