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Tectonic and climatic effects in the morphologic configuration of the coastal relief of northern Chile. This work analyzes the morphological features of the western margin of the northern Chile Coastal Cordillera, character- ized by the presence of a major Coastal Cliff. The main purpose of this research is to better understand the tectonic and climatic controls on the topography. The methodology used consists basically of a detailed study of the topography with quantitative geomorphic indexes such as incision grade, hypsometric curves and integrals, thalweg profiles and sinuosity index. These are applied to digital elevation models and satellite images. The main results show that the topography of the western margin of the Coastal Cordillera, exhibits an increasing intensity of the erosion with latitude. This increment is non uniform. The tectonic processes that produced coastal subsidence/uplift and fault activity, and the erosion of the paleotopography of Coastal Cordillera due to processes related with the construction of the Coastal Cliff and increasing rainfall, modify the morphology of the coastal border of northern Chile. The existence and conservation of the Coastal Cliff results from the existance of non-equilibrium between the uplift and erosion rates. Both rates have one-two order magnitude difference, controlled by the extreme hyperarid climate of the Atacama Desert. These conditions prevailed at least for the last 2 m.yrs. The variations in the intensity of the erosion from north to south are interpreted as the result of the southward increase in precipitacion by one order of magnitude.

13 pages, 1 figure, 1 table., Some terrestrial areas have favorable climatic and geomorphologic features that permit the preservation and accumulation of meteorites. The Atacama Desert is among the most important ones. Sixty-two, non-paired, meteorites have been collected in different places of Atacama since the late 19th century to date. Practically all types, classes and groups of meteorites have been recovered. In this work a review of the Atacama meteorites is carried out, listing all past recoveries, determining the principal strewnfield distribution patterns and providing a general overview of the features of the find locations. Principal find locations are concentrated in the Atacama Central Depression. Most of them coincide with ancient mining industries (metallic or non-metallic) or are located near towns, rail stations, tracks or human settlements. Whatever the meteorite find location was, all meteorite samples were collected on the desert surface and normally: (1) showed more than a quarter of their body exposed; (2) underwent some sign of terrestrial weathering; (3) stone meteorites have a brownish desert-varnish on hand specimen; (4) are non-oriented pieces and (5) are commonly members of a greater mass distributed in a certain place. The distribution of find locations in Atacama Desert is not as simple as it would seem on a first approach, as Atacama salt phases (environmental conditions and mineralogical alterations) have a crucial importance on meteorites weathering., We thank the institutional support and facilities of the Laboratorio de Geoquímica Aplicada and Laboratorio de Geoinformática (Departamento de Ciencias Geológicas— UCN), Chile, and Centro de Astrobiologia, Spain.