Rol del clima y la tectónica en la evolución geomorfológica de los Andes Semiáridos chilenos entre los 27-32°S

a morphometric analysis that considers hypsometry and topographic slope reveals longitudinal and latitudinal differences in the degree of maturity of the relief of the andes between 27-32°s. whereas landscape rejuvenation of the coastal cordillera takes place to the south of 29.5°s, in the main cordillera it happens south of 28.5°s. the combination of a wetter climate towards the south and the presence of segments with different tectonic features would explain these variations. longitudinally, the geomorphological features indicate the presence of a mountain front that separates the coastal cordillera and the main cordillera. between 28.5 and 30.5°s this front can be attributed to the activity of the vicu？a-san félix fault system, wich during the oligocene-early miocene would have accommodated the relative uplift of the main cordillera. in response to this tectonic activity, successive levels of cut-and-fill pediments may have been formed. during the middle miocene, there was a new episode of uplift affecting the fore-arc and it is in response to this uplift that the valleys that cross this region were excavated. between 28.5 and 30.5°s, the valleys head reached a sufficient altitude to generate fluvio-glacial erosion that allowed the incision of deep canyons in this segment of the main cordillera.