@article{OrtizSaezAlvaradoetal.2022,
  author    = {Ortiz, Gustavo and Saez, Mauro and Alvarado, Patricia and Rivas, Carolina and Garc{\´i}a, V{\´i}ctor Hugo and Alonso, Ricardo and Zullo, Fernando Morales},
  title     = {Seismotectonic characterization of the 1948 (M-W 6.9) Anta earthquake Santa Barbara System, central Andes broken foreland of northwestern Argentina},
  series = {Journal of South American earth sciences},
  volume    = {116},
  journal   = {Journal of South American earth sciences},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0895-9811},
  doi       = {10.1016/j.jsames.2022.103822},
  pages     = {15},
  year      = {2022},
  abstract  = {The region of the Andean back-arc of northwestern Argentina has been struck by several magnitude >= 6 crustal earthquakes since the first historically recorded event in 1692. One of these events corresponds to the Anta earthquake on 25 August 1948, with epicenter in the Santa Barbara System causing three deaths and severe damage in Salta and Jujuy provinces with maximum Modified Mercalli seismic intensities (MMI) of IX. We collected and digitized analog seismograms of this earthquake from worldwide seismic observatories in order to perform first-motion analysis and modeling of long-period teleseismic P-waveforms. Our results indicate a simple seismic source of M0 = 2.85 x 1019 N m consistent with a moment magnitude Mw = 6.9. We have also tested for the focal depth determining a shallow source at 8 km with a reverse focal mechanism solution with a minor dextral strike-slip component (strike 20 degrees, dip 30 degrees, rake 120 degrees) from the best fit of waveforms. Using magnitude size empirical relationships, the comparison of the obtained Mw 6.9 magnitude value and the ca. 10,000 km2 area of MMI >= IX from our seismic intensity map, which was obtained from newspaper and many historical reports, indicates a rupture length of 42 +/- 8 km for the Anta earthquake. We show our results in a 3D geological model around the epicentral area, which integrates modern seismicity, geological data, and information of a previously studied east-west cross section located a few kilometers south of the 1948 epicenter. The integration of all available information provides evidence of the re-activation of the Pie de la Sierra del Gallo fault during the 1948 Mw 6.9 shallow earthquake; this thrust fault bounds the Santa Barbara System along its western foothill.},
  language  = {en}
}
@article{ArnousZeckraVenerdinietal.2020,
  author    = {Arnous, Ahmad and Zeckra, Martin and Venerdini, Agostina and Alvarado, Patricia and Arrowsmith, Ram{\´o}n and Guillemoteau, Julien and Landgraf, Angela and Guti{\´e}rrez, Adolfo Antonio and Strecker, Manfred},
  title     = {Neotectonic Activity in the Low-Strain Broken Foreland (Santa B{\´a}rbara System) of the North-Western Argentinean Andes (26°S)},
  series = {Lithosphere},
  volume    = {2020},
  journal   = {Lithosphere},
  number    = {1},
  publisher = {GSA},
  address   = {Boulder, Colo.},
  issn      = {1947-4253},
  doi       = {10.2113/2020/8888588},
  pages     = {1 -- 25},
  year      = {2020},
  abstract  = {Uplift in the broken Andean foreland of the Argentine Santa B{\´a}rbara System (SBS) is associated with the contractional reactivation of basement anisotropies, similar to those reported from the thick-skinned Cretaceous-Eocene Laramide province of North America. Fault scarps, deformed Quaternary deposits and landforms, disrupted drainage patterns, and medium-sized earthquakes within the SBS suggest that movement along these structures may be a recurring phenomenon, with yet to be defined repeat intervals and rupture lengths. In contrast to the Subandes thrust belt farther north, where eastward-migrating deformation has generated a well-defined thrust front, the SBS records spatiotemporally disparate deformation along structures that are only known to the first order. We present herein the results of geomorphic desktop analyses, structural field observations, and 2D electrical resistivity tomography and seismic-refraction tomography surveys and an interpretation of seismic reflection profiles across suspected fault scarps in the sedimentary basins adjacent to the Candelaria Range (CR) basement uplift, in the south-central part of the SBS. Our analysis in the CR piedmont areas reveals consistency between the results of near-surface electrical resistivity and seismic-refraction tomography surveys, the locations of prominent fault scarps, and structural geometries at greater depth imaged by seismic reflection data. We suggest that this deformation is driven by deep-seated blind thrusting beneath the CR and associated regional warping, while shortening involving Mesozoic and Cenozoic sedimentary strata in the adjacent basins was accommodated by layer-parallel folding and flexural-slip faults that cut through Quaternary landforms and deposits at the surface.},
  language  = {en}
}
@misc{ArnousZeckraVenerdinietal.2020,
  author    = {Arnous, Ahmad and Zeckra, Martin and Venerdini, Agostina and Alvarado, Patricia and Arrowsmith, Ram{\´o}n and Guillemoteau, Julien and Landgraf, Angela and Guti{\´e}rrez, Adolfo Antonio and Strecker, Manfred},
  title     = {Neotectonic Activity in the Low-Strain Broken Foreland (Santa B{\´a}rbara System) of the North-Western Argentinean Andes (26°S)},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe},
  number    = {1008},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-48018},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-480183},
  pages     = {1 -- 25},
  year      = {2020},
  abstract  = {Uplift in the broken Andean foreland of the Argentine Santa B{\´a}rbara System (SBS) is associated with the contractional reactivation of basement anisotropies, similar to those reported from the thick-skinned Cretaceous-Eocene Laramide province of North America. Fault scarps, deformed Quaternary deposits and landforms, disrupted drainage patterns, and medium-sized earthquakes within the SBS suggest that movement along these structures may be a recurring phenomenon, with yet to be defined repeat intervals and rupture lengths. In contrast to the Subandes thrust belt farther north, where eastward-migrating deformation has generated a well-defined thrust front, the SBS records spatiotemporally disparate deformation along structures that are only known to the first order. We present herein the results of geomorphic desktop analyses, structural field observations, and 2D electrical resistivity tomography and seismic-refraction tomography surveys and an interpretation of seismic reflection profiles across suspected fault scarps in the sedimentary basins adjacent to the Candelaria Range (CR) basement uplift, in the south-central part of the SBS. Our analysis in the CR piedmont areas reveals consistency between the results of near-surface electrical resistivity and seismic-refraction tomography surveys, the locations of prominent fault scarps, and structural geometries at greater depth imaged by seismic reflection data. We suggest that this deformation is driven by deep-seated blind thrusting beneath the CR and associated regional warping, while shortening involving Mesozoic and Cenozoic sedimentary strata in the adjacent basins was accommodated by layer-parallel folding and flexural-slip faults that cut through Quaternary landforms and deposits at the surface.},
  language  = {en}
}