No abstract

[1] An intercomparison of recent velocity solutions for the Global Positioning System (GPS) networks constructed by the South American-Nazca Plate Project (SNAPP), based in Bolivia and Peru, and our Central Andes GPS Project (CAP), based in Chile and Argentina, indicates a velocity discontinuity of order 10 mm/yr near the boundary between these networks. We suggest that this velocity jump manifests measurement bias in the SNAPP velocity field. Our results indicate that no major slip partioning occurs within the forearc of northern Chile in response to the obliquity of subduction but that Nazca-South America plate convergence is partitioned between the forearc and the backarc regions. The present rate of shortening across the southern part of the sub-Andean belt in Argentina is 8.9 ± 1.6 mm/yr.

No abstract

This paper is a summary of the tasks that have been developed and the ones that are under development in the Argentine Republic by means of joint activities, agreements and cooperation among institutions, together with national and international scientific and educational agencies, related to:Completion, calculation, unification and link to planialtimetric networks. Gravity activities and procedures used for heights correction. Linking to neighboring countries networks. Initial leveling experiences by means of GPS technology, and results obtained.Regional and national geoid modeling. Determination of vertical crustal movements, evaluation of sea technology, variations of the mean sea level and its influence over the zero of the argentine height system.