Current rates of convergence across the central Andes : Estimates from continuous GPS observations

We present velocity solutions for 16 continuous GPS (CGPS) stations located in South America in a geodetic reference frame that nominally fixes the craton or stable core of this continent. The RMS horizontal velocity of 8 stations located within the craton is 1.3 mm/yr. Three CGPS stations located in Chile between about 33° S and 20° S have velocities in the range 19–24 mm/yr. These motions manifest current rates of convergence across the southern limb of the Central Andes. The IGS station in Arequipa, Peru (at 16.5°S) in the northern limb of the orocline, however, has a velocity of just 10 mm/yr.