6533b833fe1ef96bd129b6f9

RESEARCH PRODUCT

Geomorphological west-east-section through the north chilean andes near antofagasta

subject

description

The extremely arid western slope of the Andes near Antofagasta is an area of young tectonic movements on the one hand, but of very low erosion rates on the other. Therefore the relief is characterized by very old erosional forms, but fresh and clearly visible tectonic forms. This is quite evident from the following characteristics of a west-east-section from the Coastal Cordillera to the High Cordillera: 1. The great height and steepness of the western escarpment of the Coastal Cordillera, devoid of deep valleys. 2. The preservation of the miocene and pliocene caliche deposits with highly soluble nitrates in the eastern part of the Coastal Cordillera and of the landforms covered by them. 3. The preservation of the nearly continuous “dam” of the Coastal Cordillera, holding back the sediments from the Precordillera and the High Cordillera in the Longitudinal Depression. 4. The existence of comparatively deep endorheic salar basins directly at the foot of the very high mountains of the High Cordillera. 5. The preservation of thin but vast miocene and pliocene ignimbrite and tuff sheets even on the western slope of the High Cordillera.