Geological features such as lithological, geo-morphological and structures of Puna, in Noth-west Argentina, have been studied using satellite images in an iterative digital analysis system.

There have been clarified several features in the geologic knowledge of this region and the importance of digital images analysis in scientific geological research.

The regional lithologic characteristics were enhanced, particularly for the volcanic fields of the northern Puna, using Landsat images.

A comprehensive literature review was carried out. The available information was used by integrating it to different types of processed satellite images for the identification and analysis of relevant features of deformation and mega-regional fracturation processes. Finally, an structural general interpretation of the Puna, according to the obtained morpho-tectonic sketch is made.

A multi-spectral study of the saline and surrounding environment of El Rincon, Pocitos, Olaroz and Cauchari salt lakes is carried out. The different geologic-geomorphic units and related features to the tectonic and post-volcanic phenomena are identified and differentiated.

A multi-band Landsat TM study of the Las Burras river and the Salinas Grandes de Jujuy regions was made. The depositional stages of the alluvial cone are distinguished and the detritic and evaporitic facies, with an interpretation of the alluvial fan temporal development and mechanisms are characterized.

A digital multi-spectral analysis and processing of satellite images and aerial photographs was done to support the relationships of paleo-climatic events and the study of different paleocoast levels detected for the Laguna de Pozuelos and Salar de Jama.

The importance of glacial episodes in the environment of Puna was demonstrated by linking them to the regional climatic cycles and then contributing to new geo-morphological evidences supporting extended glacial processes in the region. It was revealed the existence of a much broader and harder glacial events than previously recognized.

Several techniques of multi-spectral analysis were combined by using specific algorithms for multi-band operation in medium and high resolution in the area of Pairique hydro-thermal alteration. Their efficiency for the recognition of chromatic and textural differences which permit their characterization and geographical district is examined.

A digital interactive analysis of high resolution satellite images made for the ignimbrite areas of Coranzulí, Vilama and Alta Cordillera allowed the recognition of different volcanic sequences, their extent and points of lava emission whose locations were previously unknown.

Finally, digital processing techniques for satellite images were developed to facilitate a detailed identification and recognition of geologic and geo-morphological features of structural meaning, its surveying in selected sectors and their neo-tectonic character enhancing.

The multi-band reflectance parameters of each lithological class were obtained and specific procedures such as the mathematical algorithms used are pointed out.

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This research was supervised by Dr. Rodolfo Amengual and presented as Tesis Work to obtain the degree of Doctor en Ciencias Geológicas at the School of Geology of the Universidad Nacional de Córdoba (Argentina) in december 1998. Was defended by the author in front of Proffessors Dr. Aldo Bonalumi (Universidad Nacional de Córdoba), Dr. Ricardo Alonso (Universidad Nacional de Córdoba) and Dr. Pablo Martínez (Universidad Nacional de Córdoba). The research was carried out supported by CONICET and Facultad de Ciencias Exactas, Físicas y Naturales of the Universidad Nacional de Córdoba, with the help of EOSAT Imaging (EE.UU.) and the Comisión Nacional de Actividades Espaciales (CONAE). The presentation was aproved with "Magna cum laude" qualification.