@misc{DonnerStreckerRoessleretal.2009,
  author    = {Donner, Stefanie and Strecker, Manfred and R{\"o}ßler, Dirk and Ghods, Abdolreza and Kr{\"u}ger, Frank and Landgraf, Angela and Ballato, Paolo},
  title     = {Earthquake source models for earthquakes in Northern Iran},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-32581},
  year      = {2009},
  abstract  = {The complex system of strike-slip and thrust faults in the Alborz Mountains, Northern Iran, are not well understood yet. Mainly structural and geomorphic data are available so far. As a more extensive base for seismotectonic studies and seismic hazard analysis we plan to do a comprehensive seismic moment tensor study also from smaller magnitudes (M < 4.5) by developing a new algorithm. Here, we present first preliminary results.},
  language  = {en}
}
@misc{DonnerRoesslerStreckeretal.2009,
  author    = {Donner, Stefanie and R{\"o}ßler, Dirk and Strecker, Manfred and Landgraf, Angela and Ballato, Paolo},
  title     = {Erweiterte Momententensorinversion und ihre seismotektonische Anwendung : Elbursgebirge, Nordiran},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-29308},
  year      = {2009},
  abstract  = {Der Elburs im Norden Irans ist ein durch die Konvergenz der Arabischen und Eurasischen Platte verursachtes doppelt konvergentes Gebirge. Das komplexe System von Blattverschiebungen und {\"U}berschiebungen sowie die Aufnahme der Deformation im Elburs ist noch nicht sehr gut verstanden. Eine neu zu entwicklende Methode zur Inversion von seismischen Momententensoren, die unterschiedliche Beobachtungen verschiedener Stationstypen kombiniert invertiert, soll die bisher haupts{\"a}chlich strukturelle/geomorphologische Datengrundlage um Momententensoren auch kleinerer Magnituden (M < 4.5) erweitern. Dies ist die notwendige Grundlage f{\"u}r detaillierte seismotektonische Studien, die wiederum die Basis f{\"u}r seismische Gef{\"a}hrdungsanalysen bilden.},
  language  = {de}
}
@phdthesis{Melnick2007,
  author    = {Melnick, Daniel},
  title     = {Neogene seismotectonics of the south-central Chile margin : subduction-related processes over various temporal and spatial scales},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12091},
  school      = {Universit{\"a}t Potsdam},
  year      = {2007},
  abstract  = {The Andean orogen is the most outstanding example of mountain building caused by the subduction of oceanic below continental lithosphere. The Andes formed by the subduction of the Nazca and Antarctic oceanic plates under the South American continent over at least ~200 million years. Tectonic and climatic conditions vary markedly along this north-south-oriented plate boundary, which thus represents an ideal natural laboratory to study tectonic and climatic segmentation processes and their possible feedbacks. Most of the seismic energy on Earth is released by earthquakes in subduction zones, like the giant 1960, Mw 9.5 event in south-central Chile. However, the segmentation mechanisms of surface deformation during and between these giant events have remained poorly understood. The Andean margin is a key area to study seismotectonic processes because of its along-strike variability under similar plate kinematic boundary conditions. Active deformation has been widely studied in the central part of the Andes, but the south-central sector of the orogen has gathered less research efforts. This study focuses on tectonics at the Neogene and late Quaternary time scales in the Main Cordillera and coastal forearc of the south-central Andes. For both domains I document the existence of previously unrecognized active faults and present estimates of deformation rates and fault kinematics. Furthermore these data are correlated to address fundamental mountain building processes like strain partitioning and large-scale segmentation. In the Main Cordillera domain and at the Neogene timescale, I integrate structural and stratigraphic field observations with published isotopic ages to propose four main phases of coupled styles of tectonics and distribution of volcanism and magmatism. These phases can be related to the geometry and kinematics of plate convergence. At the late Pleistocene timescale, I integrate field observations with lake seismic and bathymetric profiles from the Lago Laja region, located near the Andean drainage divide. These data reveal Holocene extensional faults, which define the Lago Laja fault system. This fault system has no significant strike-slip component, contrasting with the Liqui{\~n}e-Ofqui dextral intra-arc system to the south, where Holocene strike-slip markers are ubiquitous. This contrast in structural style along the arc is coincident with a marked change in along-strike fault geometries in the forearc, across the Arauco Peninsula. Thereon I propose that a net gradient in the degree of partitioning of oblique subduction occurs across the Arauco transition zone. To the north, the margin parallel component of oblique convergence is distributed in a wide zone of diffuse deformation, while to the south it is partitioned along an intra-arc, margin-parallel strike-slip fault zone. In the coastal forearc domain and at the Neogene timescale, I integrate structural and stratigraphic data from field observations, industry reflection-seismic profiles and boreholes to emphasize the influence of climate-driven filling of the trench on the mechanics and kinematics of the margin. I show that forearc basins in the 34-45°S segment record Eocene to early Pliocene extension and subsidence followed by ongoing uplift and contraction since the late Pliocene. I interpret the first stage as caused by tectonic erosion due to high plate convergence rates and reduced trench fill. The subsequent stage, in turn, is related to accretion caused by low convergence rates and the rapid increase in trench fill after the onset of Patagonian glaciations and climate-driven exhumation at ~6-5 Ma. On the late Quaternary timescale, I integrate off-shore seismic profiles with the distribution of deformed marine terraces from Isla Santa Mar{\´i}a, dated by the radiocarbon method, to show that inverted reverse faulting controls the coastal geomorphology and segmentation of surface deformation. There, a cluster of microearthquakes illuminates one of these reverse faults, which presumingly reaches the plate interface. Furthermore, I use accounts of coseismic uplift during the 1835 M>8 earthquake made by Charles Darwin, to propose that this active reverse fault has been mechanically coupled to the megathrust. This has important implications on the assessment of seismic hazards in this, and other similar regions. These results underscore the need to study plate-boundary deformation processes at various temporal and spatial scales and to integrate geomorphologic, structural, stratigraphic, and geophysical data sets in order to understand the present distribution and causes of tectonic segmentation.},
  language  = {en}
}
@phdthesis{Arnous2021,
  author    = {Arnous, Ahmad},
  title     = {Paleosismolog{\´i}a y neotect{\´o}nica del antepa{\´i}s fragmentado en el extremo sureste del Sistema Santa B{\´a}rbara, Noroeste Argentino},
  doi       = {10.25932/publishup-53527},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-535274},
  school      = {Universit{\"a}t Potsdam},
  pages     = {182},
  year      = {2021},
  abstract  = {This thesis constitutes a multidisciplinary study of the central sector of the Santa B{\´a}rbara System geological province, the tectonically active broken foreland of the central Andes of north-western Argentina. The study is based on a tectono-geomorphic characterization combined with a variety of geophysical and structural studies. The principal focus was on the faulted piedmont regions of the Sierra de La Candelaria and, to a lesser degree, the extreme south of the intermontane Met{\´a}n basin. The study region is located in the border area between the provinces of Salta and Tucum{\´a}n. The main objective was to characterize and analyze evidence of Quaternary tectonic activity in the region, in order to increase the available information on neotectonic structures and their seismogenic potential. To this end, several methods were applied and integrated, such as the interpretation of seismic reflection lines, the creation of structural sections and kinematic modeling, as well as near-surface geophysical methods, in order to explore the geometry of faults observed at the surface and to assess the behavior of potential blind faults. In a first step, a geomorphic and structural survey of the study area was carried out using LANDSAT and SENTINEL 2 multispectral satellite images, which allowed to recognize different levels of Quaternary alluvial fans and fluvial terraces that are important strain markers in the field. In a second step, different morphometric indexes were determined from digital elevation models (DEM) and combined with field observations; it was possible to identify evidence of tectonic deformation related to four neotectonic faults. In a third step, three structures (Arias, El Quemado and Copo Quile faults) were selected for more detailed studies involving Electrical Resistive Tomography (ERT) and Seismic Refraction Tomography (SRT). This part of the study enabled me to define the geometry of faults at depth, helped to infer geometric and kinematic characteristics, and confirmed the extent of recent deformation. The Arias and El Quemado faults were interpreted as reverse faults related to layer-parallel, flexuralslip faulting, while the Copo Quile fault was interpreted as a blind reverse fault. Subsequently, a joint interpretation of seismic reflection lines and well-logs from the Choromoro and Met{\´a}n basins was carried out, to decipher the principal structures and their influence on the deformation of the different sedimentary units in the intermontane basins. The obtained information was integrated into a kinematic model. This model suggests that the recent deformation is driven by a blind, deep-seated reverse fault, located under the Sierra de La Candelaria and Cantero anticline. The corresponding shortening involves the sedimentary strata of the Salta and Or{\´a}n groups in the adjacent basins, which was accommodated by faults that moved along stratal boundaries, thus bending and folding the Quaternary deposits at the surface. The kinematic model enabled identifying the approximate location of the important detachment horizons that control the overall crustal deformation style in this region. The shallowest detachment horizon is located at 4 km depth and controls deformation in a thin-skinned manner. In addition, the horizon of the thick-skinned style of deformation was identified at 21 km depth. Finally, from the integration of all the results obtained, the seismogenic potential of the faults in the study area was evaluated. The first-order faults that control deformation in the area are responsible for the large earthquakes. While, Quaternary flexural-slip faults affecting only the sedimentary cover are secondary structures that accommodate deformation and were activated very low magnitude earthquakes and/or aseismic movements. In conclusion, the results of this study allow to demonstrate that the regional fault system of intrabasinal faults in the Santa B{\´a}rbara System constitutes a potential seismogenic source in the region, where numerous towns and extensive civilian infrastructure are located. In addition, the derived kinematic model requires the existence of numerous blind structures. Only for a small number of these their presence can be unambiguously detected at the surface by geomorphic analysis, which emphasizes the need of conducting this type of studies in tectonically active regions such as the Santa B{\´a}rbara System.},
  language  = {es}
}
@phdthesis{Zeckra2020,
  author    = {Zeckra, Martin},
  title     = {Seismological and seismotectonic analysis of the northwestern Argentine Central Andean foreland},
  doi       = {10.25932/publishup-47324},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473240},
  school      = {Universit{\"a}t Potsdam},
  pages     = {vii, 120},
  year      = {2020},
  abstract  = {After a severe M W 5.7 earthquake on October 17, 2015 in El Galp{\´o}n in the province of Salta NW Argentina, I installed a local seismological network around the estimated epicenter. The network covered an area characterized by inherited Cretaceous normal faults and neotectonic faults with unknown recurrence intervals, some of which may have been reactivated normal faults. The 13 three-component seismic stations recorded data continuously for 15 months. The 2015 earthquake took place in the Santa B{\´a}rbara System of the Andean foreland, at about 17km depth. This region is the easternmost morphostructural region of the central Andes. As a part of the broken foreland, it is bounded to the north by the Subandes fold-and-thrust belt and the Sierras Pampeanas to the south; to the east lies the Chaco-Paran{\´a} basin. A multi-stage morphotectonic evolution with thick-skinned basement uplift and coeval thin-skinned deformation in the intermontane basins is suggested for the study area. The release of stresses associated with the foreland deformation can result in strong earthquakes, as the study area is known for recurrent and historical, destructive earthquakes. The available continuous record reaches back in time, when the strongest event in 1692 (magnitude 7 or intensity IX) destroyed the city of Esteco. Destructive earthquakes and surface deformation are thus a hallmark of this part of the Andean foreland. With state-of-the-art Python packages (e.g. pyrocko, ObsPy), a semi-automatic approach is followed to analyze the collected continuous data of the seismological network. The resulting 1435 hypocenter locations consist of three different groups: 1.) local crustal earthquakes (nearly half of the events belong to this group), 2.) interplate activity, of regional distance in the slab of the Nazca-plate, and 3.) very deep earthquakes at about 600km depth. My major interest focused on the first event class. Those crustal events are partly aftershock events of the El Galp{\´o}n earthquake and a second earthquake, in the south of the same fault. Further events can be considered as background seismicity of other faults within the study area. Strikingly, the seismogenic zone encompass the whole crust and propagates brittle deformation down, close to the Moho. From the collected seismological data, a local seismic velocity model is estimated, using VELEST. After the execution of various stability tests, the robust minimum 1D-velocity model implies guiding values for the composition of the local, subsurface structure of the crust. Afterwards, performing a hypocenter relocation enables the assignment of individual earthquakes to aftershock clusters or extended seismotectonic structures. This allows the mapping of previously unknown seismogenic faults. Finally, focal mechanisms are modeled for events with acurately located hypocenters, using the newly derived local velocity model. A compressive regime is attested by the majority of focal mechanisms, while the strike direction of the individual seismogenic structures is in agreement with the overall north - south orientation of the Central Andes, its mountain front, and individual mountain ranges in the southern Santa-B{\´a}rbara-System.},
  language  = {en}
}