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Abstract

GFZ acts as a global analysis center of the International GNSS Service (IGS) and provides ultra-rapid (last 24h), rapid (last day), and final (last week) solutions for GPS and GLONASS. The ultra-rapid solution series is published eight times per day with a delay of around three hours. The 3D seismic velocity models are results of a local earthquake tomography which is performed to illuminate the crustal and uppermost mantle structure beneath the southern Puna plateau and to test the delamination hypothesis. The Southern Puna is distinctive from the rest of the Central Andean plateau in having a higher topographic elevation, a thinner lithosphere and in being flanked to the south by the Chilean flat slab region. Previous investigations involving geochemical, geological and geophysical observations, have invoked lithospheric delamination to explain the distinctive magmatic and structural history, elevation and lithospheric thickness of the region. In the present study, Vp and Vp/Vs ratios were obtained using travel time variations recorded by 75 temporary seismic stations between 2007 and 2009. The earthquakes catalog (Mulcahy et al., 2014) contains 1903 local earthquakes (25077 P- and 14059 S-picks). A minimum 1D model is derived with software VELEST (Kissling et al., 1995). The 3D tomographic inversion is performed with software SIMULPS (Thurber, 1983; Evans et al., 1994). Spread values are used to define well resolved model domains (6 for Vp and 5.5 for Vp/Vs), which are calculated from the model resolution matrix (Toomey & Foulger, 1989). The data are provided as one tar.gz archive. Individual ASCII files contain, at each depth from 0 to 200 km: - Vp model (model.vp.depth_???km), format: longitude, latitude, depth, Vp perturbation, absolute Vp - Vp/Vs model (model.vpvs.depth_???km), format: longitude, latitude, depth, Vp/Vs perturbation, absolute Vp/Vs - spread values for Vp (spread.vp.depth_???km), format: longitude, latitude, depth, spread value - spread values for Vp/Vs model (spread.vpvs.depth_???km), format: longitude, latitude, depth, spread value