@article{BsdokAltenbergerConchaPerdomoetal.2020,
  author    = {Bsdok, Barbara and Altenberger, Uwe and Concha-Perdomo, Ana Elena and Wilke, Franziska Daniela Helena and Gil-Rodriguez, J. G.},
  title     = {The Santa Rosa de Viterbo meteorite, Colombia},
  series = {Journal of South American earth sciences},
  volume    = {104},
  journal   = {Journal of South American earth sciences},
  publisher = {Elsevier Science},
  address   = {Amsterdam},
  issn      = {0895-9811},
  doi       = {10.1016/j.jsames.2020.102779},
  pages     = {8},
  year      = {2020},
  abstract  = {Undifferentiated meteorites, like primitive chondrites, can contain presolar and solar nebula materials which would provide information about the origin and initial conditions of the solar system, whereas differentiated meteorites like iron meteorites, can show early phases of planetary accretion. They also provide the possibility to receive information about core properties and planetary bodies. In addition to the gain in such fundamental scientific knowledge both types are of interest for the exploration of critical raw materials (CRMs) and precious elements. The Santa Rosa de Viterbo meteorite shower, discovered 1810 in the Boyaca province of Colombia, represents a typical iron-nickel meteorite. The present study presents new structural, textural and geochemical results of one fragment of this meteorite, using reflecting microscopy, electron probe micro analyses (EPMA) and electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). The present study presents trace element concentrations of the meteorite's minerals for the first time. The sample is dominated by kamacite (alpha-FeNi). Schreibersite (FeNi3P), taenite (gamma-FeNi) and plessite (mixture of kamacite and taenite) are minor constituents. The occurrence of cohenite ((Fe,Ni,Co)(3)C) and troilite (FeS) are likely. The meteorite sample contains classical Neuman bands passing through kamacite and frequent Widmanstadtten pattern. The bandwidth of kamacite defines the meteorite as finest octahedrite. Geochemically, it is characterized as a "Type IC meteorite". While improving the characterization and classification of the Santa Rosa de Viterbo Iron Meteorite, notable concentrations of Au (>400 ppm) and Ge (>230 ppm) alongside major elements such as Fe, Ni and Co in the bulk composition of that meteorite, were proven. Major and rock-forming minerals such as kamacite and taenite incorporate hundreds of ppm of Ge whereas schreibersite, itself a minor component in that particular meteorite, is the major source for Au (>1400 ppm). In kamacite and taenite also Ir, Pd and Ga were found in minor amounts. Nano-scale inclusions or atomic clusters called nano-nuggets may have been responsible for the high concentrations of Au, Ir, Pd and Ga. Raman and Laser-induced plasma spectroscopes installed in in space probes seems suitable exploration methods for Fe-Ni meteorites, containing Ni-concentrations > 5.8 wt\% defining the meteorite as octaedrites.},
  language  = {en}
}
@misc{Ceballos2020,
  type      = {Master Thesis},
  author    = {Ceballos, Juan Camilo},
  title     = {The effect of political finance on corruption risk in Colombia},
  doi       = {10.25932/publishup-48758},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-487586},
  school      = {Universit{\"a}t Potsdam},
  pages     = {viii, 95},
  year      = {2020},
  abstract  = {Conventional wisdom holds that large sums of money poured into election campaigns are the gateway to corruption. Allegations of the corrupting influence of money in politics and policy are widespread on the national level. Yet, little empirical evidence has advanced the understanding of such a link on the local level, coupled with blurred corruption measures. This master's thesis tests the effect of campaign finance on public procurement corruption risks in Colombian municipalities, focusing on donations, small donations, and financial disclosure. To that end, I seized publicly disclosed contribution-level data from the 2015 municipal elections and a novel index of institutionalized public procurement corruption risks based upon contract-level data from the near population of local governments. The analysis shows that donations are negatively associated with overall corruption risk, yet they affect specific corruption risks differently. By contrast, small donations seem to correlate positively with direct awarding for a sub-sample of medium-sized municipalities, whereas in their large-sized counterparts the effect of the former on institutionalized corruption is adverse. Finally, financial misreporting is positively linked with market competition restrictions and direct awarding. In the conclusion, I discuss the implications of these findings for future research and outline a series of policy recommendations.},
  language  = {en}
}
@article{WeberCardonaValenciaetal.2011,
  author    = {Weber, Marion and Cardona, A. and Valencia, V. and Altenberger, Uwe and Lopez-Martinez, M. and Tobon, M. and Zapata, Sebastian Henao and Zapata, G. and Concha, A. E.},
  title     = {Geochemistry and geochronology of the Guajira Eclogites, northern Colombia evidence of a metamorphosed primitive Cretaceous Caribbean Island-arc},
  series = {Geologica acta},
  volume    = {9},
  journal   = {Geologica acta},
  number    = {3-4},
  publisher = {Facultat de Geologia, Divisio III, Ci{\`e}ncies Experimentals i Matem{\`a}tiques, Universitat de Barcelona},
  address   = {Barcelona},
  issn      = {1695-6133},
  doi       = {10.1344/105.000001740},
  pages     = {425 -- 443},
  year      = {2011},
  abstract  = {The chemical composition of eclogites, found as boulders in a Tertiary conglomerate from the Guajira Peninsula, Colombia suggests that these rocks are mainly metamorphosed basaltic andesites. They are depleted in LILE elements compared to MORB, have a negative Nb-anomaly and flat to enriched REE patterns, suggesting that their protoliths evolved in a subduction related tectonic setting. They show island-arc affinities and are similar to primitive island-arc rocks described in the Caribbean. The geochemical characteristics are comparable to low-grade greenschists from the nearby Etpana Terrane, which are interpreted as part of a Cretaceous intra-oceanic arc. These data support evidence that the eclogites and the Etpana terrane rocks formed from the same volcano-sedimentary sequence. Part of this sequence was accreted onto the margin and another was incorporated into the subduction channel and metamorphosed at eclogite facies conditions. Ar-40-Ar-39 ages of 79.2 +/- 1.1Ma and 82.2 +/- 2.5Ma determined on white micas, separated from two eclogite samples, are interpreted to be related to the cooling of the main metamorphic event. The formation of a common volcano-sedimentary protolith and subsequent metamorphism of these units record the ongoing Late Cretaceous continental subduction of the South American margin within the Caribbean intra-oceanic arc subduction zone. This gave way to an arc-continent collision between the Caribbean and the South American plates, where this sequence was exhumed after the Campanian.},
  language  = {en}
}
@phdthesis{TabaresJimenez2015,
  author    = {Tabares Jim{\´e}nez, Adri{\´a}n de Jes{\´u}s},
  title     = {Palabras de fundadores, forasteros y cachacos},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-85630},
  school      = {Universit{\"a}t Potsdam},
  pages     = {227},
  year      = {2015},
  abstract  = {Die vorliegende Dissertation analysiert die Mentalit{\"a}ten der b{\"u}rgerlichen Bewohner Bogotas 19. Jahrhundert. Einblicke in die Fremd- und Eigenperspektiven der Bogotaner werden durch die Analyse von Reiseliteratur gewonnen. Methodologisch st{\"u}tzt sich die Arbeit auf den Vergleich zwischen europ{\"a}ischen Reiseberichten aus dem 19. Jh., Chroniken aus dem 16. Jh. sowie zwei kolumbianische Romane aus dem fr{\"u}hen 20.. Jh. Die Texte werden historiographisch behandelt; obwohl sie unterschiedlichen literarischen Genres angeh{\"o}ren, weisen sie einen gemeinsamen autobiographischen Charakter auf. Aus den Erfahrungen und Gedanken der Reisenden werden v.a. die Auswirkungen der geographischen und sozialen Isolation thematisiert, sowie die Einfl{\"u}sse von politischen und religi{\"o}sen Diskursen auf die Bildung von b{\"u}rgerlichem Gedankengut.},
  language  = {es}
}
@book{FigariLayus2010,
  author    = {Figari Lay{\´u}s, Rosario},
  title     = {The role of transitional justice in the midst of ongoing armed conflicts},
  series = {Potsdamer Studien zu Staat, Recht und Politik},
  journal   = {Potsdamer Studien zu Staat, Recht und Politik},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-063-2},
  issn      = {1867-2663},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-42500},
  publisher      = {Universit{\"a}t Potsdam},
  pages     = {111},
  year      = {2010},
  abstract  = {Between 2002 and 2006 the Colombian government of {\´A}lvaro Uribe counted with great international support to hand a demobilization process of right-wing paramilitary groups, along with the implementation of transitional justice policies such as penal prosecutions and the creation of a National Commission for Reparation and Reconciliation (NCRR) to address justice, truth and reparation for victims of paramilitary violence. The demobilization process began when in 2002 the United Self Defence Forces of Colombia (Autodefensas Unidas de Colombia, AUC) agreed to participate in a government-sponsored demobilization process. Paramilitary groups were responsible for the vast majority of human rights violations for a period of over 30 years. The government designed a special legal framework that envisaged great leniency for paramilitaries who committed serious crimes and reparations for victims of paramilitary violence. More than 30,000 paramilitaries have demobilized under this process between January 2003 and August 2006. Law 975, also known as the "Justice and Peace Law", and Decree 128 have served as the legal framework for the demobilization and prosecutions of paramilitaries. It has offered the prospect of reduced sentences to demobilized paramilitaries who committed crimes against humanity in exchange for full confessions of crimes, restitution for illegally obtained assets, the release of child soldiers, the release of kidnapped victims and has also provided reparations for victims of paramilitary violence. The Colombian demobilization process presents an atypical case of transitional justice. Many observers have even questioned whether Colombia can be considered a case of transitional justice. Transitional justice measures are often taken up after the change of an authoritarian regime or at a post-conflict stage. However, the particularity of the Colombian case is that transitional justice policies were introduced while the conflict still raged. In this sense, the Colombian case expresses one of the key elements to be addressed which is the tension between offering incentives to perpetrators to disarm and demobilize to prevent future crimes and providing an adequate response to the human rights violations perpetrated throughout the course of an internal conflict. In particular, disarmament, demobilization and reintegration processes require a fine balance between the immunity guarantees offered to ex-combatants and the sought of accountability for their crimes. International law provides the legal framework defining the rights to justice, truth and reparations for victims and the corresponding obligations of the State, but the peace negotiations and conflicted political structures do not always allow for the fulfillment of those rights. Thus, the aim of this article is to analyze what kind of transition may be occurring in Colombia by focusing on the role that transitional justice mechanisms may play in political negotiations between the Colombian government and paramilitary groups. In particular, it seeks to address to what extent such processes contribute to or hinder the achievement of the balance between peacebuilding and accountability, and thus facilitate a real transitional process.},
  language  = {en}
}
@phdthesis{Parra2008,
  author    = {Parra, Mauricio},
  title     = {Cenozoic foreland-basin evolution in the northern Andes : insights from thermochronology and basin analysis in the Eastern Cordillera, Colombia},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-29333},
  school      = {Universit{\"a}t Potsdam},
  year      = {2008},
  abstract  = {The modern foreland basin straddling the eastern margin of the Andean orogen is the prime example of a retro-arc foreland basin system adjacent to a subduction orogen. While widely studied in the central and southern Andes, the spatial and temporal evolution of the Cenozoic foreland basin system in the northern Andes has received considerably less attention. This is in part due to the complex geodynamic boundary conditions, such as the oblique subduction and accretion of the Caribbean plates to the already complex interaction between the Nazca and the South American plates. In the Colombian Andes, for example, a foreland basin system has been forming since ~80 Ma over an area previously affected by rift tectonics during the Mesozoic. This setting of Cenozoic contractile deformation superposed on continental crust pre-strained by extensional processes thus represents a natural, yet poorly studied experimental set-up, where the role of tectonic inheritance on the development of foreland basin systems can be evaluated. However, a detailed documentation of the early foreland basin evolution in this part of the Andes has thus far only been accomplished in the more internal sectors of the orogen. In this study, I integrate new structural, sedimentological and biostratigraphic data with low-temperature thermochronology from the eastern sector of the Colombian Andes, in order to provide the first comprehensive account of mountain building and related foreland basin sedimentation in this part of the orogen, and to assess as to what extent pre-existent basement anisotropies have conditioned the locus of foreland deformation in space and time. In the Medina Basin, along the eastern flank of the Eastern Cordillera, I integrated detailed structural mapping and new sedimentological data with a new chronostratigraphic framework based on detailed palynology that links an eastward-thinning early Oligocene to early Miocene syntectonic wedge containing rapid facies changes with an episode of fast tectonic subsidence starting at ~30 Ma. This record represents the first evidence of topographic loading generated by slip along the principal basement-bounding thrusts in the Eastern Cordillera to the west of the basin and thus constrains the onset of mountain building in this area. A comprehensive assessment of exhumation patterns based on zircon fission-track (ZFT), apatite fission-track (AFT) analysis and thermal modelling reveals the location of these thrust loads to have been located along the contractionally reactivated Soapaga Fault in the axial sector of the Eastern Cordillera. Farther to the east, AFT and ZFT data also document the onset of thrust-induced exhumation associated with contractional reactivation of the main range-bounding Servita Fault at ~20 Ma. Associated with this episode of orogenic growth, peak burial temperature estimates based on vitrinite reflectance data in the Cenozoic sedimentary record of the adjacent Medina Basin documents earlier incorporation of the western sector of the basin into the advancing fold and thrust belt. I combined these new thermochronological data with published AFT analyses and known chronologic indicators of brittle deformation in order to evaluate the patterns of orogenic-front migration in the Andes of central Colombia. This spatiotemporal analysis of deformation reveals an episodic pattern of eastward migration of the orogenic front at an average rate of 2.5-2.7 mm/yr during the Late Cretaceous-Cenozoic. I identified three major stages of orogen propagation. First, following initiation of mountain building in the Central Cordillera during the Late Cretaceous, the orogenic front propagate eastward at slow rates (0.5-3.1 mm/yr) until early Eocene times. Such slow orogenic advance would have resulted from limited accretionary flux related to slow and oblique (SW-NE-oriented) convergence of the Farallon and South American plates during that time. A second stage of rapid orogenic advance (4.0-18.0 mm/yr) during the middle-late Eocene, and locally of at least 100 mm/yr in the middle Eocene, resulted from initial tectonic inversion of the Eastern Cordillera. I correlate this episode of rapid orogen-front migration with an increase in the accretionary flux triggered by acceleration in convergence and a rotation of the convergence vector to a more orogen-perpendicular direction. Finally, stagnation of the Miocene deformation front along former rift-bounding reactivated faults in the eastern flank of the Eastern Cordillera led to a decrease in the rates of orogenic advance. Post-late Miocene-Pliocene thrusting along the actively deforming front of the Eastern Cordillera at this latitude suggests averaged Miocene-Holocene orogen propagation rates of 1.2-2.1 mm/yr. In addition, ZFT data suggest that exhumation along the eastern flank of the orogen occurred at moderate rates of ~0.3 mm/yr during the Miocene, prior to an acceleration of exhumation since the Pliocene, as suggested by recently published AFT data. In order to evaluate the relations between thrust loading and sedimentary facies evolution in the foreland, I analyzed gravel progradation in the foreland basin system. In particular, I compared one-dimensional Eocene to Pliocene sediment accumulation rates in the Medina basin with a three-dimensional sedimentary budget based on the interpretation of ~1800 km of industry-style seismic reflection profiles and borehole data tied to the new chronostratigraphic framework. The sedimentological data from the Medina Basin reveal rapid accumulation of fluvial and lacustrine sediments at rates of up to ~ 0.5 mm/yr during the Miocene. Provenance data based on gravel petrography and paleocurrents reveal that these Miocene fluvial systems were sourced by Upper Cretaceous and Paleocene sedimentary units exposed to the west, in the Eastern Cordillera. Peak sediment-accumulation rates in the upper Carbonera Formation and the Guayabo Group occur during episodes of gravel progradation in the proximal foredeep in the Early and Late Miocene. I interpreted this positive correlation between sediment accumulation and gravel deposition as the direct consequence of thrust activity in the Servita-Lengup{\´a} Fault. This contrasts with current models relating gravel progradation to episodes of tectonic quiescence in more distal portions of foreland basin systems and calls for a re-evaluation of tectonic history interpretations inferred from sedimentary units in other mountain belts. In summary, my results document a late Eocene-early Miocene eastward advance of the topographic loads associated with the leading edge of deformation in the northern Andes of Colombia. Crustal thickening of the Eastern Cordillera associated with initiation of thrusting along the Servit{\´a} Fault illustrates that this sector of the Andean orogen acquired ~90\% of its present width already by the early Miocene (~20 Ma). My data thus demonstrate that inherited crustal anisotropies, such as the former rift-bounding faults of the Eastern Cordillera, favour a non-systematic progression of foreland basin deformation through time by preferentially concentrating accommodation of slip and thrust-loading. These new chronology of exhumation and deformation associated with specific structures in the Colombian Andes also constitutes an important advance towards the understanding of models for hydrocarbon maturation, migration and trap formation along the prolific petroleum province of the Llanos Basin in the modern foredeep area.},
  language  = {en}
}
@phdthesis{VasquezParra2007,
  author    = {V{\´a}squez Parra, M{\´o}nica Fernanda},
  title     = {Mafic magmatism in the Eastern Cordillera and Putumayo Basin, Colombia : causes and consequences},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13183},
  school      = {Universit{\"a}t Potsdam},
  year      = {2007},
  abstract  = {The Eastern Cordillera of Colombia is mainly composed of sedimentary rocks deposited since early Mesozoic times. Magmatic rocks are scarce. They are represented only by a few locally restricted occurrences of dykes and sills of mafic composition presumably emplaced in the Cretaceous and of volcanic rocks of Neogene age. This work is focused on the study of the Cretaceous magmatism with the intention to understand the processes causing the genesis of these rocks and their significance in the regional tectonic setting of the Northern Andes. The magmatic rocks cut the Cretaceous sedimentary succession of black shales and marlstones that crop out in both flanks of the Eastern Cordillera. The studied rocks were classified as gabbros (C{\´a}ceres, Pacho, Rodrigoque), tonalites (C{\´a}ceres, La Corona), diorites and syenodiorites (La Corona), pyroxene-hornblende gabbros (Pacho), and pyroxene-hornblendites (Pajarito). The gabbroic samples are mainly composed of plagioclase, clinopyroxene, and/or green to brown hornblende, whereas the tonalitic rocks are mainly composed of plagioclase and quartz. The samples are highly variable in crystal sizes from fine- to coarse-grained. Accessory minerals such as biotite, titanite and zircon are present. Some samples are characterized by moderate to strong alteration, and show the presence of epidote, actinolite and chlorite. Major and trace element compositions of the rocks as well as the rock-forming minerals show significant differences in the geochemical and petrological characteristics for the different localities, suggesting that this magmatism does not result from a single melting process. The wide compositional spectrum of trace elements in the intrusions is characteristic for different degrees of mantle melting and enrichment of incompatible elements. MORB- and OIB-like compositions suggest at least two different sources of magma with tholeiitic and alkaline affinity, respectively. Evidence of slab-derived fluids can be recognized in the western part of the basin reflected in higher Ba/Nb and Sr/P ratios and also in the Sr radiogenic isotope ratios, which is possible a consequence of metasomatism in the mantle due to processes related to the presence of a previously subducted slab. The trace element patterns evidence an extensional setting in the Cretaceous basin producing a continental rift, with continental crust being stretched until oceanic crust was generated in the last stages of this extension. Electron microprobe analyses (EMPA) of the major elements and synchrotron radiation micro-X-ray fluorescence (μ-SRXRF) analyses of the trace element composition of the early crystallized minerals of the intrusions (clinopyroxenes and amphiboles) reflect the same dual character that has been found in the bulk-rock analyses. Despite the observed alteration of the rocks, the mineral composition shows evidences for an enriched and a relative depleted magma source. Even the normalization of the trace element concentrations of clinopyroxenes and amphiboles to the whole rock nearly follows the pattern predicted by published partition coefficients, suggesting that the alteration did not change the original trace element compositions of the investigated minerals. Sr-Nd-Pb isotope data reveal a large isotopic variation but still suggest an initial origin of the magmas in the mantle. Samples have moderate to highly radiogenic compositions of 143Nd/144Nd and high 87Sr/86Sr ratios and follow a trend towards enriched mantle compositions, like the local South American Paleozoic crust. The melts experienced variable degrees of contamination by sediments, crust, and seawater. The age corrected Pb isotope ratios show two separated groups of samples. This suggests that the chemical composition of the mantle below the Northern Andes has been modified by the interaction with other components resulting in a heterogeneous combination of materials of diverse origins. Although previous K/Ar age dating have shown that the magmatism took place in the Cretaceous, the high error of the analyses and the altered nature of the investigated minerals did preclude reliable interpretations. In the present work 40Ar/39Ar dating was carried out. The results show a prolonged history of magmatism during the Cretaceous over more than 60 Ma, from ~136 to ~74 Ma (Hauterivian to Campanian). Pre-Cretaceous rifting phases occurred in the Triassic-Jurassic for the western part of the basin and in the Paleozoic for the eastern part. Those previous rifting phases are decisive mechanisms controlling the localization and composition of the Cretaceous magmatism. Therefore, it is the structural position and not the age of the intrusions which preconditions the kind of magmatism and the degree of melting. The divergences on ages are the consequence of the segmentation of the basin in several sub-basins which stretching, thermal evolution and subsidence rate evolved independently. The first hypothesis formulated at the beginning of this investigation was that the Cretaceous gabbroic intrusions identified in northern Ecuador could be correlated with the intrusions described in the Eastern Cordillera. The mafic occurrences should mark the location of the most subsiding places of the large Cretaceous basin in northern South America. For this reason, the gabbroic intrusions cutting the Cretaceous succession in the Putumayo Basin, southern Colombia, were investigated. The results of the studies were quite unexpected. The petrologic and geochemical character of the magmatic rocks indicates subduction-related magmatism. K/Ar dating of amphibole yields a Late Miocene to Pliocene age (6.1 ± 0.7 Ma) for the igneous event in the basin. Although there is no correlation between this magmatic event and the Cretaceous magmatic event, the data obtained has significant tectonic and economic implications. The emplacement of the Neogene gabbroic rocks coincides with the late Miocene/Pliocene Andean orogenic uplift as well as with a significant pulse of hydrocarbon generation and expulsion.},
  language  = {en}
}