The Andean foreland is divided into morphotectonic provinces characterized by diverse deformation styles and seismogenic behavior partially stemming from distinct geological histories that preceded the current phase of subduction. The transition between the high Andes and the eastern foreland is exposed to numerous natural hazards and contains critical economic infrastructure, yet we know relatively little about regional active tectonics due to few geophysical investigations. Here we use waveforms collected during a 15-month-long seismic network deployment in the Santa Bárbara System (SBS) of northwest Argentina following the 2015 Mw 5.7 El Galpón earthquake to determine the distribution and magnitude of local earthquakes, obtain a regional 1D seismic velocity model, and improve our overall understanding of SBS neotectonics. Of the nearly 1200 recorded earthquakes, ~700 occurred in the crust with half of the moment release associated with events deeper than 25 km. The depth extent of seismicity supports the notion that the SBS upper and middle crust are homogeneous and that the lower crust is composed of granulites. These conditions likely formed during Paleozoic mountain building and Salta Rift-related Cretaceous magmatism, which dehydrated the crust. We find no clear indications that a shallow, low-angle detachment fault inferred to have been active during Cretaceous rifting exerts a strong control on modern deformation in contrast to the active décollement beneath the adjacent fold-and-thrust belt of the Subandes to the north. It remains unclear how active, inverted normal faults in the SBS shallow crust connect to the deeper zones of seismicity.

The launches of the Sentinel-1 synthetic aperture radar satellites in 2014 and 2016 started a new era of high-resolution velocity and strain rate mapping for the continents. However, multiple challenges exist in tying independently processed velocity data sets to a common reference frame and producing high-resolution strain rate fields. We analyse Sentinel-1 data acquired between 2014 and 2019 over the northeast Tibetan Plateau, and develop new methods to derive east and vertical velocities with ~100 m resolution and ~1 mm/yr accuracy across an area of 440,000 km^2. By implementing a new method of combining horizontal gradients of filtered east and interpolated north velocities, we derive the first ~1 km resolution strain rate field for this tectonically active region. The strain rate fields show concentrated shear strain along the Haiyuan and East Kunlun Faults, and local contractional strain on fault junctions, within the Qilianshan thrusts, and around the Longyangxia Reservoir. The Laohushan-Jingtai creeping section of the Haiyuan Fault is highlighted in our data set by extremely rapid strain rates. Strain across unknown portions of the Haiyuan Fault system, including shear on the eastern extension of the Dabanshan Fault and contraction at the western flank of the Quwushan, highlight unmapped tectonic structures. In addition to the uplift across most of the lowlands, the vertical velocities also contain climatic, hydrological or anthropogenic-related deformation signals. We demonstrate the enhanced view of large-scale active tectonic processes provided by high-resolution velocities and strain rates derived from Sentinel-1 data and highlight associated wide-ranging research applications.