@article{SobelSchoenbohmChenetal.2011,
  author    = {Sobel, Edward and Schoenbohm, Lindsay M. and Chen, Jie and Thiede, Rasmus Christoph and Stockli, Daniel F. and Sudo, Masafumi and Strecker, Manfred},
  title     = {Late Miocene-Pliocene deceleration of dextral slip between Pamir and Tarim: Implications for Pamir orogenesis},
  series = {EARTH AND PLANETARY SCIENCE LETTERS},
  volume    = {304},
  journal   = {EARTH AND PLANETARY SCIENCE LETTERS},
  number    = {3-4},
  publisher = {ELSEVIER SCIENCE BV},
  address   = {AMSTERDAM},
  issn      = {0012-821X},
  doi       = {10.1016/j.epsl.2011.02.012},
  pages     = {369 -- 378},
  year      = {2011},
  abstract  = {The timing of the late Cenozoic collision between the Pamir salient and the Tien Shan as well as changes in the relative motion between the Pamir and Tarim are poorly constrained. The northern margin of the Pamir salient indented northward by similar to 300 km during the late Cenozoic, accommodated by south-dipping intracontinental subduction along the Main Pamir Thrust (MPT) coupled to strike-slip faults on the eastern flank of the orogen and both strike-slip and thrust faults on the western margin. The Kashgar-Yecheng transfer system (KYTS) is the main dextral slip shear zone separating Tarim from the Eastern Pamir, with an estimated cumulative offset of similar to 280 km at an average late Cenozoic dextral slip rate of 11-15 mm/a (Cowgill, 2010). In order to better constrain the slip history of the KYTS, we collected thermochronologic samples along the eastward-flowing, deeply incised, antecedent Tashkorgan-Yarkand River, which crosses the fault system on the eastern flank of the orogen. We present 29 new biotite (40)Ar/(39)Ar ages, apatite and zircon (U-Th-Sm)/He ages, and apatite fission track (AFT) analysis, combined with published muscovite and biotite (40)Ar/(39)Ar and AFT data, to create a unique thermochronologic dataset in this poorly studied and remote region. We constrain the timing of four major N-trending faults: the latter three are strands of the KYTS. The westernmost, the Kuke fault, experienced significant dip-slip, west-side-up displacement between > 12 and 6 Ma. To the east, within the KYTS, our new thermochronologic data and geomorphic observations suggest that the Kumtag and Kusilaf dextral slip faults have been inactive since at least 3-5 Ma. Long-term incision rates across the Aertashi dextral slip fault, the easternmost strand of the KYTS, are compatible with slow horizontal slip rates of 1.7-5.3 mm/a over the past 3 to 5 Ma. In summary, these data show that the slip rate of the KYTS decreased substantially during the late Miocene or Pliocene. Furthermore, Miocene-present regional kinematic reconstructions suggest that this deceleration reflects the substantial increase of northward motion of Tarim rather than a significant decrease of the northward velocity of the Pamir. (C) 2011 Elsevier B.V. All rights reserved.},
  language  = {en}
}
@phdthesis{Hintersberger2013,
  author    = {Hintersberger, Esther},
  title     = {The role of extension during the evolution of the NW Indian Himalaya},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-66179},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {The evolution of most orogens typically records cogenetic shortening and extension. Pervasive normal faulting in an orogen, however, has been related to late syn- and post-collisional stages of mountain building with shortening focused along the peripheral sectors of the orogen. While extensional processes constitute an integral part of orogenic evolution, the spatiotemporal characteristics and the kinematic linkage of structures related to shortening and extension in the core regions of the orogen are often not well known. Related to the India-Eurasia collision, the Himalaya forms the southern margin of the Tibetan Plateau and constitutes the most prominent Cenozoic type example of a collisional orogen. While thrusting is presently observed along the foothills of the orogen, several generations of extensional structures have been detected in the internal, high-elevation regions, both oriented either parallel or perpendicular to the strike of the orogen. In the NW Indian Himalaya, earthquake focal mechanisms, seismites and ubiquitous normal faulting in Quaternary deposits, and regional GPS measurements reveal ongoing E-W extension. In contrast to other extensional structures observed in the Himalaya, this extension direction is neither parallel nor perpendicular to the NE-SW regional shortening direction. In this study, I took advantage of this obliquity between the trend of the orogen and structures related to E-W oriented extension in order to address the question of the driving forces of different extension directions. Thus, extension might be triggered triggered by processes within the Tibetan Plateau or originates from the curvature of the Himalayan orogen. In order to elaborate on this topic, I present new fault-kinematic data based on systematic measurements of approximately 2000 outcrop-scale brittle fault planes with displacements of up to several centimeters that cover a large area of the NW Indian Himalaya. This new data set together with field observations relevant for relative chronology allows me to distinguish six different deformation styles. One of the main results are that the overall strain pattern derived from this data reflects the regionally important contractional deformation pattern very well, but also reveals significant extensional deformation. In total, I was able to identify six deformation styles, most of which are temporally and spatially linked and represent protracted shortening, but also significant extensional directions. For example, this is the first data set where a succession of both, arc-normal and E-W extension have been documented in the Himalaya. My observations also furnish the basis for a detailed overview of the younger extensional deformation history in the NW Indian Himalaya. Field and remote-sensing based geomorphic analyses, and geochronologic 40Ar/39Ar data on synkinematic muscovites along normal faults help elucidate widespread E-W extension in the NW Indian Himalaya which must have started at approximately 14-16 Ma, if not earlier. In addition, I documented and mapped fault scarps in Quaternary sedimentary deposits using satellite imagery and field inspection. Furthermore, I made field observations of regional normal faults, compiled structures from geological maps and put them in a regional context. Finally, I documented seismites in lake sediments close to the currently most active normal fault in the study area in order to extend the (paleo) seismic record of this particular fault. Taken together, this data sets document that E-W extension is the dominant active deformation style in the internal parts of the orogen. In addition, the combined field, geomorphic and remote-sensing data sets prove that E-W extension occurs in a much more larger region toward the south and west than the seismicity data have suggested. In conclusion, the data presented here reveal the importance of extension in a region, which is still dominated by ongoing collision and shortening. The regional fault distribution and cross-cutting relationships suggest that extension parallel and perpendicular to the strike of the orogen are an integral part of the southward propagation of the active thrust front and the associated lateral growth of the Himalayan arc. In the light of a wide range of models proposed for extension in the Himalaya and the Tibetan plateau, I propose that E-W extension in the NW Indian Himalaya is transferred from the Tibetan Plateau due the inability of the Karakorum fault (KF) to adequately accommodate ongoing E-W extension on the Tibetan Plateau. Furthermore, in line with other observations from Tibet, the onset of E-W normal faulting in the NW Himalaya may also reflect the attainment of high topography in this region, which generated crustal stresses conducive to spatially extensive extension.},
  language  = {en}
}
@phdthesis{Pingel2015,
  author    = {Pingel, Heiko},
  title     = {Mountain-range uplift \& climate-system interactions in the Southern Central Andes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82301},
  school      = {Universit{\"a}t Potsdam},
  pages     = {xii, 178},
  year      = {2015},
  abstract  = {Zwei h{\"a}ufig diskutierte Aspekte der sp{\"a}tk{\"a}nozoischen Gebirgsbildung der Anden sind der Zeitpunkt sowie die Art und Weise der Heraushebung des Puna-Plateaus und seiner Randgebiete innerhalb der Ostkordillere und die damit verbundenen klimatischen {\"A}nderungen in NW Argentinien. Die Ostkordillere trennt die Bereiche des endorheischen, ariden Plateaus von semiariden und extern entw{\"a}sserten intermontanen Becken sowie dem humiden Andenvorland im Osten. Diese Unterschiede verdeutlichen die Bedeutung der {\"o}stlichen Flanken der Anden als orografische Barrieren gegen{\"u}ber feuchten Luftmassen aus dem Osten und spiegelt sich auch in ausgepr{\"a}gten Relief- und Topografiegradienten, der Niederschlagsverteilung, und der Effizienz von Oberfl{\"a}chenprozessen wider. Obwohl das {\"u}bergeordnete Deformationsmuster in diesem Teil der Anden eine ostw{\"a}rts gerichtete Wanderung der Deformationsprozesse im Gebirge indiziert, gibt es hier keine klar definierte Deformationsfront. Hebungsvorg{\"a}nge und die damit im Zusammenhang stehenden Sedimentprozesse setzen r{\"a}umlich und zeitlich sehr unterschiedlich ein. Zudem gestalten periodisch wiederkehrende Deformationsereignisse innerhalb intermontaner Becken und diachrone Hebungsvorg{\"a}nge, durch Reaktivierung {\"a}lterer Sockelstrukturen im Vorland, eine detaillierte Auswertung der r{\"a}umlich-zeitlichen Hebungsmuster zus{\"a}tzlich schwierig. Die vorliegende Arbeit konzentriert sich haupts{\"a}chlich auf die tektonische Entwicklung der Ostkordillere im Nordwesten Argentiniens, die Ablagerungsgeschichte ihrer intermontanen Sedimentbecken und die topografische Entwicklung der Ostflanke des andinen Puna-Plateaus. Im Allgemeinen sind sich die Sedimentbecken der Ostkordillere und der angrenzenden Provinzen, den Sierras Pampeanas und der Santa B{\´a}rbara Region, den durch St{\"o}rungen begrenzten und mit Sedimenten verf{\"u}llten Becken der hochandinen Plateauregion sehr {\"a}hnlich. Deutliche Unterschiede zur Puna bestehen aber dennoch, denn wiederholte Deformations-, Erosions- und Sedimentationsprozesse haben in den intermontanen Becken zu einer vielf{\"a}ltigen Stratigrafie, {\"U}berlagerungsprozessen und einer durch tektonische Prozesse und klimatischen Wandel charakterisierten Landschaft beigetragen. Je nach Erhaltungsgrad k{\"o}nnen in einigen F{\"a}llen Spuren dieser sediment{\"a}ren und tektonischen Entwicklung bis in die Zeit zur{\"u}ckreichen, als diese Bereiche des Gebirges noch Teil eines zusammenh{\"a}ngenden und unverformten Vorlandbeckens waren. Im Nordwesten Argentiniens enthalten k{\"a}nozoische Sedimente zahlreiche datierbare und geochemisch korrelierbare Vulkanaschen, die nicht nur als wichtige Leithorizonte zur Entschl{\"u}sselung tektonischer und sediment{\"a}rer Ereignisse dienen. Die vulkanischen Gl{\"a}ser dieser Aschen archivieren außerdem Wasserstoff-Isotopenverh{\"a}ltnisse fr{\"u}herer Oberfl{\"a}chenwasser, mit deren Hilfe - im Vergleich mit den Isotopenverh{\"a}ltnissen rezenter meteorischer W{\"a}sser - die r{\"a}umliche und zeitliche Entstehung orografischer Barrieren und tektonisch erzwungene Klima- und Umweltver{\"a}nderungen verfolgt werden k{\"o}nnen. Uran-Blei-Datierungen an Zirkonen aus den vulkanischen Aschelagen und die Rekonstruktion sediment{\"a}rer Pal{\"a}otransportrichtungen im intermontanen Humahuaca-Becken in der Ostkordillere (23.5° S) deuten an, dass das heutige Becken bis vor etwa 4.2 Ma Bestandteil eines gr{\"o}ßtenteils uneingeschr{\"a}nkten Ablagerungsbereichs war, der sich bis ins Vorland erstreckt haben muss. Deformation und Hebung {\"o}stlich des heutigen Beckens sorgten dabei f{\"u}r eine fortschreitende Entkopplung des Entw{\"a}sserungsnetzes vom Vorland und eine Umlenkung der Flussl{\"a}ufe nach S{\"u}den. In der Folge erzwang die weitere Hebung der Gebirgsbl{\"o}cke das Abregnen {\"o}stlicher Luftmassen in immer {\"o}stlicher gelegene Bereiche. Zudem k{\"o}nnen periodische Schwankungen der hydrologischen Verbindung des Beckens mit dem Vorland im Zusammenhang mit der Ablagerung und Erosion m{\"a}chtiger Beckenf{\"u}llungen identifiziert werden. Systematische Beziehungen zwischen Verwerfungen, regionalen Diskontinuit{\"a}ten und verstellten Terrassenfl{\"a}chen verweisen außerdem auf ein generelles Muster beckeninterner Deformation, vermutlich als Folge umfangreicher Beckenerosion und damit verbundenen {\"A}nderungen im tektonischen Spannungsfeld der Region. Einige dieser Beobachtungen k{\"o}nnen anhand ver{\"a}nderter Wasserstoff-Isotopenkonzentrationen vulkanischer Gl{\"a}ser aus der k{\"a}nozoischen Stratigrafie untermauert werden. Die δDg-Werte zeigen zwei wesentliche Trends, die einerseits in Verbindung mit Oberfl{\"a}chenhebung innerhalb des Einzugsgebiets zwischen 6.0 und 3.5 Ma stehen und andererseits mit dem Einsetzen semiarider Bedingungen durch Erreichen eines Schwellenwertes der Topografie der {\"o}stlich gelegenen Gebirgsz{\"u}ge nach 3.5 Ma erkl{\"a}rt werden k{\"o}nnen. Tektonisch bedingte Unterbrechung der Sedimentzufuhr aus westlich gelegenen Liefergebieten um 4.2 Ma und die folgende Hinterland-Aridifizierung deuten weiterhin auf die M{\"o}glichkeit hin, dass diese Prozesse die Folge eines lateralen Wachstums des Puna-Plateaus sind. Diese Aridifizierung im Bereich der Puna resultierte in einem ineffizienten, endorheischen Entw{\"a}sserungssystem, das dazu beigetragen hat, das Plateau vor Einschneidung und externer Entw{\"a}sserung zu bewahren und Reliefgegens{\"a}tze aufgrund fortgesetzter Beckensedimentation reduzierte. Die diachrone Natur der Hebungen und Beckenbildungen sowie deren Auswirkungen auf das Flusssystem im angrenzenden Vorland wird sowohl durch detaillierte Analysen der Sedimentherkunft und Transportrichtungen als auch Uran-Blei-Datierungen im Lerma- und Met{\´a}n-Becken (25° S) weiterhin unterstrichen. Das wird besonders deutlich am Beispiel der isolierten Hebung der Sierra de Met{\´a}n vor etwa 10 Ma, die mehr als 50 km von der aktiven orogenen Front im Westen entfernt liegt. Ab 5 Ma sind typische Lithologien der Puna nicht mehr in den Vorlandsedimenten nachweisbar, welches die weitere Hebung innerhalb der Ostkordillere und die hydrologische Isolation des Angastaco-Beckens in dieser Region dokumentiert. Im Sp{\"a}tplioz{\"a}n und Quart{\"a}r ist die Deformation letztlich {\"u}ber das gesamte Vorland verteilt und bis heute aktiv. Um die Beziehungen zwischen tektonisch kontrollierten Ver{\"a}nderungen der Topografie und deren Einfluss auf atmosph{\"a}rische Prozesse besser zu verstehen, werden in dieser Arbeit weitere altersspezifische Wasserstoff-Isotopendaten vulkanischer Gl{\"a}ser aus dem zerbrochenen Vorland, dem Angastaco-Becken in der {\"U}bergangsregion zwischen Ostkordillere und Punarand und anderer intermontaner Becken weiter s{\"u}dlich vorgestellt. Die Resultate dokumentieren {\"a}hnliche H{\"o}henlagen der untersuchten Regionen bis ca. 7 Ma, gefolgt von Hebungsprozessen im Bereich des Angastaco-Beckens. Ein Vergleich mit Isotopendaten vom benachbarten Puna-Plateau hilft abrupte δDg-Schwankungen in den intermontanen Daten zu erkl{\"a}ren und untermauert die Existenz wiederkehrender Phasen verst{\"a}rkt konvektiver Wetterlagen im Plioz{\"a}n, {\"a}hnlich heutigen Bedingungen. In dieser Arbeit werden gel{\"a}ndeorientierte und geochemische Methoden kombiniert, um Erkenntnisse {\"u}ber die Abl{\"a}ufe von topografiebildenden Deformations- und Hebungsprozessen zu gewinnen und Wechselwirkungen mit der daraus resultierenden Niederschlagsverteilung, Erosion und Sedimentation innerhalb tektonisch aktiver Gebirge zu erforschen. Diese Erkenntnisse sind f{\"u}r ein besseres Verst{\"a}ndnis von Subduktionsgebirgen essentiell, besonders hinsichtlich des Deformationsstils und der zeitlich-r{\"a}umlichen Beziehungen bei der Hebung und Sedimentbeckenbildung. Diese Arbeit weist dar{\"u}berhinaus auf die Bedeutung stabiler Isotopensysteme zur Beantwortung pal{\"a}oaltimetrischer Fragestellungen und zur Erforschung von Pal{\"a}oumweltbedingungen hin und liefert wichtige Erkenntnisse f{\"u}r einen kritischen Umgang mit solchen Daten in anderen Regionen.},
  language  = {en}
}
@phdthesis{Dey2016,
  author    = {Dey, Saptarshi},
  title     = {Tectonic and climatic control on the evolution of the Himalayan mountain front},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-103390},
  school      = {Universit{\"a}t Potsdam},
  pages     = {xii, 118},
  year      = {2016},
  abstract  = {Variations in the distribution of mass within an orogen may lead to transient sediment storage, which in turn might affect the state of stress and the level of fault activity. Distinguishing between different forcing mechanisms causing variations of sediment flux and tectonic activity, is therefore one of the most challenging tasks in understanding the spatiotemporal evolution of active mountain belts. The Himalayan mountain belt is one of the most significant Cenozoic collisional mountain belt, formed due to collision between northward-bound Indian Plate and the Eurasian Plate during the last 55-50 Ma. Ongoing convergence of these two tectonic plates is accommodated by faulting and folding within the Himalayan arc-shaped orogen and the continued lateral and vertical growth of the Tibetan Plateau and mountain belts adjacent to the plateau as well as regions farther north. Growth of the Himalayan orogen is manifested by the development of successive south-vergent thrust systems. These thrust systems divide the orogen into different morphotectonic domains. From north to south these thrusts are the Main Central Thrust (MCT), the Main Boundary Thrust (MBT) and the Main Frontal Thrust (MFT). The growing topography interacts with moisture-bearing monsoonal winds, which results in pronounced gradients in rainfall, weathering, erosion and sediment transport toward the foreland and beyond. However, a fraction of this sediment is trapped and transiently stored within the intermontane valleys or 'dun's within the lower-elevation foothills of the range. Improved understanding of the spatiotemporal evolution of these sediment archives could provide a unique opportunity to decipher the triggers of variations in sediment production, delivery and storage in an actively deforming mountain belt and support efforts to test linkages between sediment volumes in intermontane basins and changes in the shallow crustal stress field. As sediment redistribution in mountain belts on timescales of 102-104 years can effect cultural characteristics and infrastructure in the intermontane valleys and may even impact the seismotectonics of a mountain belt, there is a heightened interest in understanding sediment-routing processes and causal relationships between tectonism, climate and topography. It is here at the intersection between tectonic processes and superposed climatic and sedimentary processes in the Himalayan orogenic wedge, where my investigation is focused on. The study area is the intermontane Kangra Basin in the northwestern Sub-Himalaya, because the characteristics of the different Himalayan morphotectonic provinces are well developed, the area is part of a region strongly influenced by monsoonal forcing, and the existence of numerous fluvial terraces provides excellent strain markers to assess deformation processes within the Himalayan orogenic wedge. In addition, being located in front of the Dhauladhar Range the region is characterized by pronounced gradients in past and present-day erosion and sediment processes associated with repeatedly changing climatic conditions. In light of these conditions I analysed climate-driven late Pleistocene-Holocene sediment cycles in this tectonically active region, which may be responsible for triggering the tectonic re-organization within the Himalayan orogenic wedge, leading to out-of-sequence thrusting, at least since early Holocene. The Kangra Basin is bounded by the MBT and the Sub-Himalayan Jwalamukhi Thrust (JMT) in the north and south, respectively and transiently stores sediments derived from the Dhauladhar Range. The Basin contains ~200-m-thick conglomerates reflecting two distinct aggradation phases; following aggradation, several fluvial terraces were sculpted into these fan deposits. 10Be CRN surface exposure dating of these terrace levels provides an age of 53.4±3.2 ka for the highest-preserved terrace (AF1); subsequently, this surface was incised until ~15 ka, when the second fan (AF2) began to form. AF2 fan aggradation was superseded by episodic Holocene incision, creating at least four terrace levels. We find a correlation between variations in sediment transport and ∂18O records from regions affected by the Indian Summer Monsoon (ISM). During strengthened ISMs sand post-LGM glacial retreat, aggradation occurred in the Kangra Basin, likely due to high sediment flux, whereas periods of a weakened ISM coupled with lower sediment supply coincided with renewed re-incision. However, the evolution of fluvial terraces along Sub-Himalayan streams in the Kangra sector is also forced by tectonic processes. Back-tilted, folded terraces clearly document tectonic activity of the JMT. Offset of one of the terrace levels indicates a shortening rate of 5.6±0.8 to 7.5±1.0 mm.a-1 over the last ~10 ka. Importantly, my study reveals that late Pleistocene/Holocene out-of-sequence thrusting accommodates 40-60\% of the total 14±2 mm.a-1 shortening partitioned throughout the Sub-Himalaya. Importantly, the JMT records shortening at a lower rate over longer timescales hints towards out-of-sequence activity within the Sub-Himalaya. Re-activation of the JMT could be related to changes in the tectonic stress field caused by large-scale sediment removal from the basin. I speculate that the deformation processes of the Sub-Himalaya behave according to the predictions of critical wedge model and assume the following: While >200m of sediment aggradation would trigger foreland-ward propagation of the deformation front, re-incision and removal of most of the stored sediments (nearly 80-85\% of the optimum basin-fill) would again create a sub-critical condition of the wedge taper and trigger the retreat of the deformation front. While tectonism is responsible for the longer-term processes of erosion associated with steepening hillslopes, sediment cycles in this environment are mainly the result of climatic forcing. My new 10Be cosmogenic nuclide exposure dates and a synopsis of previous studies show the late Pleistocene to Holocene alluvial fills and fluvial terraces studied here record periodic fluctuations of sediment supply and transport capacity on timescales of 1000-100000 years. To further evaluate the potential influence of climate change on these fluctuations, I compared the timing of aggradation and incision phases recorded within remnant alluvial fans and terraces with continental climate archives such as speleothems in neighboring regions affected by monsoonal precipitation. Together with previously published OSL ages yielding the timing of aggradation, I find a correlation between variations in sediment transport with oxygen-isotope records from regions affected by the Indian Summer Monsoon (ISM). Accordingly, during periods of increased monsoon intensity (transitions from dry and cold to wet and warm periods - MIS4 to MIS3 and MIS2 to MIS1) (MIS=marine isotope stage) and post-Last Glacial Maximum glacial retreat, aggradation occurred in the Kangra Basin, likely due to high sediment flux. Conversely, periods of weakened monsoon intensity or lower sediment supply coincide with re-incision of the existing basin-fill. Finally, my study entails part of a low-temperature thermochronology study to assess the youngest exhumation history of the Dhauladhar Range. Zircon helium (ZHe) ages and existing low-temperature data sets (ZHe, apatite fission track (AFT)) across this range, together with 3D thermokinematic modeling (PECUBE) reveals constraints on exhumation and activity of the range-bounding Main Boundary Thrust (MBT) since at least mid-Miocene time. The modeling results indicate mean slip rates on the MBT-fault ramp of ~2 - 3 mm.a-1 since its activation. This has lead to the growth of the >5-km-high frontal Dhauladhar Range and continuous deep-seated exhumation and erosion. The obtained results also provide interesting constraints of deformation patterns and their variation along strike. The results point towards the absence of the time-transient 'mid-crustal ramp' in the basal decollement and duplexing of the Lesser Himalayan sequence, unlike the nearby regions or even the central Nepal domain. A fraction of convergence (~10-15\%) is accommodated along the deep-seated MBT-ramp, most likely merging into the MHT. This finding is crucial for a rigorous assessment of the overall level of tectonic activity in the Himalayan morphotectonic provinces as it contradicts recently-published geodetic shortening estimates. In these studies, it has been proposed that the total Himalayan shortening in the NW Himalaya is accommodated within the Sub-Himalaya whereas no tectonic activity is assigned to the MBT.},
  language  = {en}
}
@phdthesis{Georgieva2016,
  author    = {Georgieva, Viktoria},
  title     = {Neotectonics \& Cooling History of the Southern Patagonian Andes},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-104185},
  school      = {Universit{\"a}t Potsdam},
  pages     = {xviii, 200 Seiten},
  year      = {2016},
  abstract  = {The collision of bathymetric anomalies, such as oceanic spreading centers, at convergent plate margins can profoundly affect subduction dynamics, magmatism, and the structural and geomorphic evolution of the overriding plate. The Southern Patagonian Andes of South America are a prime example for sustained oceanic ridge collision and the successive formation and widening of an extensive asthenospheric slab window since the Middle Miocene. Several of the predicted upper-plate geologic manifestations of such deep-seated geodynamic processes have been studied in this region, but many topics remain highly debated. One of the main controversial topics is the interpretation of the regional low-temperature thermochronology exhumational record and its relationship with tectonic and/or climate-driven processes, ultimately manifested and recorded in the landscape evolution of the Patagonian Andes. The prominent along-strike variance in the topographic characteristics of the Andes, combined with coupled trends in low-temperature thermochronometer cooling ages have been interpreted in very contrasting ways, considering either purely climatic (i.e. glacial erosion) or geodynamic (slab-window related) controlling factors. This thesis focuses on two main aspects of these controversial topics. First, based on field observations and bedrock low-temperature thermochronology data, the thesis addresses an existing research gap with respect to the neotectonic activity of the upper plate in response to ridge collision - a mechanism that has been shown to affect the upper plate topography and exhumational patterns in similar tectonic settings. Secondly, the qualitative interpretation of my new and existing thermochronological data from this region is extended by inverse thermal modelling to define thermal histories recorded in the data and evaluate the relative importance of surface vs. geodynamic factors and their possible relationship with the regional cooling record. My research is centered on the Northern Patagonian Icefield (NPI) region of the Southern Patagonian Andes. This site is located inboard of the present-day location of the Chile Triple Junction - the juncture between the colliding Chile Rise spreading center and the Nazca and Antarctic Plates along the South American convergent margin. As such this study area represents the region of most recent oceanic-ridge collision and associated slab window formation. Importantly, this location also coincides with the abrupt rise in summit elevations and relief characteristics in the Southern Patagonian Andes. Field observations, based on geological, structural and geomorphic mapping, are combined with bedrock apatite (U-Th)/He and apatite fission track (AHe and AFT) cooling ages sampled along elevation transects across the orogen. This new data reveals the existence of hitherto unrecognized neotectonic deformation along the flanks of the range capped by the NPI. This deformation is associated with the closely spaced oblique collision of successive oceanic-ridge segments in this region over the past 6 Ma. I interpret that this has caused a crustal-scale partitioning of deformation and the decoupling, margin-parallel migration, and localized uplift of a large crustal sliver (the NPI block) along the subduction margin. The location of this uplift coincides with a major increase of summit elevations and relief at the northern edge of the NPI massif. This mechanism is compatible with possible extensional processes along the topographically subdued trailing edge of the NPI block as documented by very recent and possibly still active normal faulting. Taken together, these findings suggest a major structural control on short-wavelength variations in topography in the Southern Patagonian Andes - the region affected by ridge collision and slab window formation. The second research topic addressed here focuses on using my new and existing bedrock low-temperature cooling ages in forward and inverse thermal modeling. The data was implemented in the HeFTy and QTQt modeling platforms to constrain the late Cenozoic thermal history of the Southern Patagonian Andes in the region of the most recent upper-plate sectors of ridge collision. The data set combines AHe and AFT data from three elevation transects in the region of the Northern Patagonian Icefield. Previous similar studies claimed far-reaching thermal effects of the approaching ridge collision and slab window to affect patterns of Late Miocene reheating in the modelled thermal histories. In contrast, my results show that the currently available data can be explained with a simpler thermal history than previously proposed. Accordingly, a reheating event is not needed to reproduce the observations. Instead, the analyzed ensemble of modelled thermal histories defines a Late Miocene protracted cooling and Pliocene-to-recent stepwise exhumation. These findings agree with the geological record of this region. Specifically, this record indicates an Early Miocene phase of active mountain building associated with surface uplift and an active fold-and-thrust belt, followed by a period of stagnating deformation, peneplanation, and lack of synorogenic deposition in the Patagonian foreland. The subsequent period of stepwise exhumation likely resulted from a combination of pulsed glacial erosion and coeval neotectonic activity. The differences between the present and previously published interpretation of the cooling record can be reconciled with important inconsistencies of previously used model setup. These include mainly the insufficient convergence of the models and improper assumptions regarding the geothermal conditions in the region. This analysis puts a methodological emphasis on the prime importance of the model setup and the need for its thorough examination to evaluate the robustness of the final outcome.},
  language  = {en}
}
@article{JaraMunozMelnickPedojaetal.2019,
  author    = {Jara-Munoz, Julius and Melnick, Daniel and Pedoja, Kevin and Strecker, Manfred},
  title     = {TerraceM-2: A MatlabR (R) Interface for Mapping and Modeling Marine and Lacustrine Terraces},
  series = {Frontiers in Earth Science},
  volume    = {7},
  journal   = {Frontiers in Earth Science},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {2296-6463},
  doi       = {10.3389/feart.2019.00255},
  pages     = {18},
  year      = {2019},
  abstract  = {The morphology of marine and lacustrine terraces has been largely used to measure past sea- and lake-level positions and estimate vertical deformation in a wealth of studies focused on climate and tectonic processes. To obtain accurate morphometric assessments of terrace morphology we present TerraceM-2, an improved version of our MatlabR (R) graphic-user interface that provides new methodologies for morphometric analyses as well as landscape evolution and fault-dislocation modeling. The new version includes novel routines to map the elevation and spatial distribution of terraces, to model their formation and evolution, and to estimate fault-slip rates from terrace deformation patterns. TerraceM-2 has significantly improves its processing speed and mapping capabilities, and includes separate functions for developing customized workflows beyond the graphic-user interface. We illustrate these new mapping and modeling capabilities with three examples: mapping lacustrine shorelines in the Dead Sea to estimate deformation across the Dead Sea Fault, landscape evolution modeling to estimate a history of uplift rates in southern Peru, and dislocation modeling of deformed marine terraces in California. These examples also illustrate the need to use topographic data of different resolutions. The new modeling and mapping routines of TerraceM-2 highlight the advantages of an integrated joint mapping and modeling approach to improve the efficiency and precision of coastal terrace metrics in both marine and lacustrine environments.},
  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}
}