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Bedrock geology of Truitt Creek map area (NTS 105L/1) and tectonic implications for the northern Canadian Cordillera, central Yukon TerritoryGladwin, Kaesy 14 November 2008 (has links)
In southern central Yukon Territory, Canada, a northwest-trending 267 Ma ophiolitic assemblage defines the Tummel fault zone (TFZ), which juxtaposes Paleozoic miogeoclinal strata of Cassiar terrane with metavolcanic and metasedimentary rocks of Yukon-Tanana terrane. Basalt, greenstone, and chert occur in the TFZ and are correlated with Slide Mountain terrane. Northeast of the TFZ, pelitic and semipelitic rocks of the Kechika Group are overlain by carbonate of the Askin Group in Cassiar terrane. Southwest of the TFZ, Yukon-Tanana terrane comprises Devonian-Mississippian quartzofeldspathic basement (the Snowcap Complex) overlain by Mississippian clastic and arc-derived rocks of the Drury, Pelmac, and Little Salmon formations. The ca. 105 Ma Glenlyon Batholith and its satellite plutons intrude Cassiar terrane and the TFZ, imposing a contact metamorphic aureole that overprints earlier metamorphic features in rocks of Cassiar and Yukon-Tanana terranes and the TFZ, and indicates pre-105 Ma juxtaposition of these three tectonic assemblages.
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COPS: Cluster optimized proximity scalingRusch, Thomas, Mair, Patrick, Hornik, Kurt January 2015 (has links) (PDF)
Proximity scaling (i.e., multidimensional scaling and related methods) is a versatile statistical
method whose general idea is to reduce the multivariate complexity in a data set by employing suitable proximities between the data points and finding low-dimensional
configurations where the fitted distances optimally approximate these proximities. The ultimate goal, however, is often not only to find the optimal configuration but to infer statements about the similarity of objects in the high-dimensional space based on the the similarity in the configuration. Since these two goals are somewhat at odds it can happen that the resulting optimal configuration makes inferring similarities rather difficult. In that case the solution lacks "clusteredness" in the configuration (which we call "c-clusteredness"). We present a version of proximity scaling, coined cluster optimized
proximity scaling (COPS), which solves the conundrum by introducing a more clustered appearance into the configuration while adhering to the general idea of multidimensional scaling. In COPS, an arbitrary MDS loss function is parametrized by monotonic transformations
and combined with an index that quantifies the c-clusteredness of the solution. This index, the OPTICS cordillera, has intuitively appealing properties with respect to measuring c-clusteredness. This combination of MDS loss and index is called "cluster optimized loss" (coploss) and is minimized to push any configuration towards a more clustered appearance. The effect of the method will be illustrated with various examples: Assessing
similarities of countries based on the history of banking crises in the last 200 years, scaling Californian counties with respect to the projected effects of climate change and their social vulnerability, and preprocessing a data set of hand written digits for subsequent classification by nonlinear dimension reduction. (authors' abstract) / Series: Discussion Paper Series / Center for Empirical Research Methods
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Bedrock geology of Truitt Creek map area (NTS 105L/1) and tectonic implications for the northern Canadian Cordillera, central Yukon TerritoryGladwin, Kaesy 14 November 2008 (has links)
In southern central Yukon Territory, Canada, a northwest-trending 267 Ma ophiolitic assemblage defines the Tummel fault zone (TFZ), which juxtaposes Paleozoic miogeoclinal strata of Cassiar terrane with metavolcanic and metasedimentary rocks of Yukon-Tanana terrane. Basalt, greenstone, and chert occur in the TFZ and are correlated with Slide Mountain terrane. Northeast of the TFZ, pelitic and semipelitic rocks of the Kechika Group are overlain by carbonate of the Askin Group in Cassiar terrane. Southwest of the TFZ, Yukon-Tanana terrane comprises Devonian-Mississippian quartzofeldspathic basement (the Snowcap Complex) overlain by Mississippian clastic and arc-derived rocks of the Drury, Pelmac, and Little Salmon formations. The ca. 105 Ma Glenlyon Batholith and its satellite plutons intrude Cassiar terrane and the TFZ, imposing a contact metamorphic aureole that overprints earlier metamorphic features in rocks of Cassiar and Yukon-Tanana terranes and the TFZ, and indicates pre-105 Ma juxtaposition of these three tectonic assemblages.
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Plant nutrient mobilization and acquisition strategies: adaptation to water and nutrient availabilityStock, Svenja 25 March 2021 (has links)
No description available.
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Basement fault influence on the Bicorb-Quesa Salt Wall kinematics, insights from Magnetotelluric and Paleomagnetic techniques on Salt TectonicsRubinat Cabanas, Marc 27 June 2012 (has links)
El text del Capítol 3 ha estat retirat seguint instruccions de l’autor de la tesi, en existir participació d’empreses, existir conveni de confidencialitat o existeix la possibilitat de generar patents / The text of Chapter 3 has been withdrawn on the instructions of the author, as there is participation of undertakings, confidentiality agreement or the ability to generate patent / The Bicorb-Quesa salt wall is located on the external Prebetics, an excellent natural laboratory to observe the diapir evolution because of their excellent outcrops. This area, located on the limit between the Iberian Massif, the Betic Range and the Valencian Trough; preserves the deformation caused by four deformation stages: two extensional and two extensive phases.
The complexity and changing geometry of the salt wall lead us to use different techniques, some of them rarely used on salt tectonics studies, in order to provide significant information on the knowledge of the salt wall kinematics. The Magnetotelluric data shows the wide range of electrical resistivity materials values. This technique allowed us to recognize a basement fault with a vertical throw of 1000 m. which was active during the Triassic to Lower Cretaceous and likewise elucidate about the salt wall shape and the salt location. The Paleomagnetic data provide valuable information about the rotation suffered on the area both the syn-diapiric basins and the diapir, revealing rotation on different areas. This information together with the internal diapir structure and the overburden structure makes possible to interpret the initiation and reactivation of salt wall as driven by thin-skinned contractional deformation of the overburden. These processes were preferentially developed on the top of a pre-existing basement fault. A comprehensive analysis brings into relief the role played by the propagation direction sense of the cover deformation and the dip sense of the basement fault.
This thesis contributes on the scientific knowledge of the salt tectonics, in its kinematics and evolution in different tectonic settings. The salt tectonics is also a geological branch very attractive for the oil industry as it generates one of the most important trap sources. / La presència de materials evaporítics condiciona l’estructura que es desenvoluparà en un àrea ja que les propietats reològiques de les evaporites són molt diferents a les d’altres materials. Especialment la sal, que es deforma plàsticament, és menys densa i més dèbil que la majoria dels materials (Jackson i Talbot, 1986; Jackson i Vendeville, 1994). Aquestes propietats permetran la formació de coixins salins, diapirs salins, parets salines, llengües salines, etc. La generació d’aquestes estructures i el fet de que la sal sigui impermeable propicia la formació de trampes per hidrocarburs i la possibilitat d’emmagatzemar CO2 o altres residus. Aquest fet els hi dóna a les estructures salines interès econòmic i facilita l’avenç científic en la matèria, com mostra la publicació d’articles que han millorat el coneixement d’aquestes estructures a partir dels anys ‘90 (ex. Vendeville i Jackson 1992; Jackson 1995; Letouzey et al. 1995; Ge et al. 1997; Rowan et al. 2003; Stewart 2006; Hudec i Jackson 2007, etc.)
L’efecte causat a una cobertora fràgil, pel moviment de una falla normal de basament sobre la qual tenim un nivell de desenganxament dúctil ha estat ampliament estudiat (Koyi et al. 1993; Nalpas i Brun 1993; Jackson i Vendeville 1994; Vendeville et al. 1995; Stewart i Clark 1999; Withjack i Callaway 2000; Dooley et al. 2003; 2005). També, amb la mateixa disposició de materials fràgils-dúctils, ha estat investigada la inversió de les falles normals de basament durant una etapa compressiva (Letouzey et al. 1995; Stewart i Clark 1999; Krzywiec 2004; Ferrer et al. 2012). Per altra banda, la deformació de pell prima provocada per una època compressiva a sobre de un nivell de desenganxament també ha estat estudiada (ex. Chapple 1978; Davis i Engelder 1985; Coward i Stewart 1995; Sans i Koyi 2001), i amb la mateixa geometria les conseqüències de una compressió en un diapir previ (Vendeville i Nilsen 1995; Canerot et al 2005; Roca et al 2006; Callot et al. 2007; Dooley et al. 2009). Tanmateix, no hi ha cap estudi previ publicat en revistes científiques internacionals que descrigui la deformació per compressió de la pell prima prèviament afectada per una falla de basament. Per tal d’omplir aquest buit, s’ha estudiat la paret salina de Bicorb-Quesa, molt adequada ja que està localitzada a sobre d’una falla de basament, en una zona afectada per compressió amb deformació de pell prima (Roca et al 1996, 2006).
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El Macizo Central de los Picos de Europa: geomorfología y sus implicaciones geoecológicas en la alta montaña cantábricaGonzález Trueba, Juan José 12 January 2007 (has links)
Esta tesis aplicando las bases teórico-metodológicas de la geoecología de montaña trata de establecer la organización altitudinal del paisaje de montaña del Macizo Central de los Picos de Europa. El macizo es considerado como un sistema organizado altitudinalmente en pisos geoecológicos, como resultado de los cambios morfo/bioclimáticos derivados de la altitud. El relieve se presenta como el elemento clave en la configuración del paisaje natural de esta montaña, hasta el punto de llegar a definirlo como un paisaje fundamentalmente geomorfológico.Se diferencian dos pisos de alta montaña y dos pisos de montaña media, separados entre sí por una franja de transición geoecológica: a) Alta Montaña Rocosa (> 2.200 m), b) Alta Montaña Supraforestal (1.800-2.200 m), c) Franja de Transición Geoecológica entre AM/MM (1.400-1.600 m,), d) Montaña Media Forestal (600/800 y 1.400/1.600 m), e) Laderas Bajas-Fondos de Valle de Montaña Media, M.M. muy antropizada (< 600/800 m). / This Thesis applies the theoretical basis of mountain geoecology to establish the altitudinal organization of the mountain landscape of the Central Massif of Picos de Europa (Cantabrian Range). The massif is considered to be a system altitudinally organized in belts, as result of the morpho/bioclimatic changes deriving from altitude. Relief is the main element of the natural landscape of this mountain massif, to the extent of defining it as a fundamentally geomorphological landscape. Two geoecological belts of high mountain and two of the middle mountain are distinguished, connected by a geoecological transition belt: a) Rocky high mountain (> 2200 m), b) Upper forest high mountain belt (1800 and 2200 m): c) Geoecological Transition HM/MM (1400/1600 and 1800 m), d) Forest Middle Mountain (600/800 and 1400/1600 m), and e) Low slopes and valley bottoms - Middle mountain highly antropized (<600/800 m).
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Sedimentary, structural, and provenance record of the Cianzo basin, Puna plateau-Eastern Cordillera boundary, NW ArgentinaSiks, Benjamin Charles 15 July 2011 (has links)
The fault-bounded Cianzo basin represents a Cenozoic intermontane depocenter between the Puna plateau and Eastern Cordillera of the central Andean fold-thrust belt in northern Argentina. New characterizations of fold-thrust structure, nonmarine sedimentation, and sediment provenance for the shortening-induced Cianzo basin at 23°S help constrain the origin, interconnectedness, and subsequent uplift and exhumation of the basin, which may serve as an analogue for other intermontane hinterland basins in the Andes. Structural mapping of the Cianzo basin reveals SW and NE-plunging synclines within the >6000 m-thick, upsection coarsening Cenozoic clastic succession in the shared footwall of the N-striking, E-directed Cianzo thrust fault and transverse, NE-striking Hornocal fault. Growth stratal relationships within upper Miocene levels of the succession indicate syncontractional sedimentation directly adjacent to the Hornocal fault.
Measured stratigraphic sections and clastic sedimentary lithofacies of Cenozoic basin-fill deposits show upsection changes from (1) a distal fluvial system recorded by
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fine-grained, paleosol-rich, heavily bioturbated sandstones and mudstones (Paleocene‒Eocene Santa Bárbara Subgroup, ~400 m), to (2) a braided fluvial system represented by cross-stratified sandstones and interbedded mudstones with 0.3 to 8 m upsection-fining sequences (Upper Eocene–Oligocene Casa Grande Formation, ~1400 m), to (3) a distributary fluvial system in the distal sectors of a distributary fluvial megafan represented by structureless sheetflood sandstones, stratified pebble conglomerates and sandstones, and interbedded overbank mudstones (Miocene Río Grande Formation, ~3300 m), to (4) a proximal alluvial fan system with thick conglomerates interbedded with thin discontinuous sandstone lenses (upper Miocene Pisungo Formation, ~1600 m).
New 40Ar/39Ar geochronological results for five interbedded volcanic tuffs indicate distributary fluvial deposition of the uppermost Río Grande Formation from 16.31 ± 0.6 Ma to 9.69 ± 0.05 Ma. Sandstone petrographic results show distinct upsection trends in lithic and feldspar content in the Casa Grande, Río Grande, and Pisungo formations, potentially distinguishing western magmatic arc (Western Cordillera) sediment sources from evolving eastern thrust-belt sources (Puna‒Eastern Cordillera). In addition to growth stratal relationships and 40Ar/39Ar constraints, conglomerate clast compositions reflect distinct lithologic differences, constraining the activation of the Cianzo thrust and coeval movement on the reactivated Hornocal fault. Finally, U-Pb geochronological analyses of sandstone detrital zircon populations in conjunction with paleocurrent data and depositional facies patterns help distinguish localized sources from more distal sources west of the basin, revealing a systematic eastward advance of Eocene to Miocene fold-thrust deformation in the central Andes of northern Argentina. / text
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Structure, stratigraphy, and U-Pb zircon-titanite geochronology of the Aley carbonatite complex, northeast British Columbia: Evidence for Antler-aged orogenesis in the Foreland Belt of the Canadian CordilleraMcLeish, Duncan Forbes 26 April 2013 (has links)
The tectonic significance and age of carbonatite intrusions in the western Foreland Belt of the Canadian Cordillera are poorly constrained. Recent 1:5,000 scale field mapping of one of these carbonatite intrusions, the Aley carbonatite (NTS 94 B/5), has demonstrated that it was emplaced as a syn-kinematic sill, coeval with a major nappe-forming tectonic event. Determining the age of the Aley carbonatite therefore provides a means of directly dating tectonism related to carbonatite magmatism. A U-Pb titanite age of 365.9 +/- 2.1 Ma was obtained from the Ospika pipe, an ultramafic diatreme spatially and genetically related to the carbonatite. We interpret the Late Devonian age of the Ospika pipe to be the minimum possible age of the carbonatite and syn-magmatic nappe-forming tectonic event. The maximum possible age of the carbonatite is constrained by the Early Devonian age of the Road River Group (ca. 410 Ma), the youngest strata intruded by carbonatite dykes and involved in the nappe forming event. Our dating results for the Aley carbonatite closely correlate with U-Pb zircon and perovskite ages obtained for the Ice River carbonatite complex in the western Foreland Belt of the southern Canadian Cordillera, and support the interpretation of carbonatite intrusions of the western Foreland Belt as genetically linked components of an alkaline-carbonatitic magmatic province. Structural, stratigraphic, and geochronological data from the Aley area indicate that deformation was similar in style to, and coeval with, structures attributable to the Antler Orogeny, and are consistent with the Antler orogen having extended the length of Cordilleran margin from the southern United States to Alaska. Deformed alkaline-carbonatite intrusions that characterize continental suture zones in Africa and Tibet may provide an analogue for the Aley carbonatite and correlative alkaline-carbonatite complexes in the western Foreland Belt. / Graduate / 0372 / mcleish@uvic.ca
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El patrimonio material y espiritual en el proceso de formación de dos provincias de la Patagonia argentina / El patrimonio material y espiritual en el proceso de formación de dos provincias de la Patagonia argentinaColantuono, María Rosa, Pérez, Gabriela, Vives, Graciela 10 April 2018 (has links)
The provinces of Río Negro and Neuquén are located in the northern Argentinean Patagonia. One of them, Neuquén, is at the foothills of the Andes; meanwhile, the other extends from this mountain chain to the Atlantic Ocean. In spite of their vicinity, their material and spiritual patrimonies are different enough to give each their own identity. At Neuquén, the richest petroleum deposits of Argentina are found, which provide most of the oil and gasto the country, giving a good share to Neuquén of the revenues from taxes collected. Furthermore, Neuquén also has other means for its economy based on landscape resources that have attracted the development of many tourist resorts. Lastly, it has fruit agriculture and flsheries with a heavy share of investment from the prívate sector.In relation to their spiritual patrimony, even if the two provinces have contactpoints due to their territorial organization, they have also differences since both territories acquired the rank of provinces. In Neuquén, political and cultural factors determine local incentives toward development that leads to the formation of a regio nal society different from that of Río Negro. A local political party not enrolled in national parties plays a decisive role in development after the 1960s, and in the deflnition of the regional identity. At Río Negro, the migratory groups, especially Europeans, have heavily influenced in the formation of the local incentives to development. This paper explores ideas around these topics and tries to make a comparative analysis with respect to the formation of the local incentives and their development. / Las provincias de Río Negro y Neuquén están ubicadas en la porción septentrional de la Patagonia argentina. Una de ellas -Neuquén- se recuesta sobre la cordillera de los Andes, mientras que la otra -Río Negro- se extiende desde este cordón monta ñoso hasta el Atlántico.A pesar de su vecindad, sus patrimonios materiales y espirituales presentan particularidades que otorgan a cada una de las provincias una identidad propia. En el caso neuquino, su territorio se caracteriza por albergar los yacimientos de hidrocarburos más ricos del país, haciendo de esta provincia la primera productora de petróleo y gas. Esto le significa al Gobierno de Neuquén un importante ingreso por las regalías-aproximadamente el 80% de su presupuesto-, y para la sociedad en general, unaeconomía fuertemente dependiente de los recursos provenientes de los hidrocarbu ros, así como dependiente del Estado. Río Negro, por su parte, se caracteriza por una economía más diversificada: recursos paisajísticos que han promovido un importante desarrollo turístico, fruticultura y pesca, con una mayor participación del sector pri vado. En cuanto al patrimonio espiritual, si bien tienen puntos de contacto en lo que respecta al proceso de organización territorial, también presentan especificidades a partir del momento en que ambos territorios toman el carácter de provincias. Con respecto a Neuquén, factores políticos y culturales determinan incentivos locales para el desarrollo que conducen a la formación de una sociedad regional diferente de su vecina rionegrina. Un partido político local no enrolado en ninguna de las corrientes nacionales mayoritarias jugará un rol decisivo a partir de los años sesenta en el desa rrollo y definición de la identidad regional. En el caso rionegrino, los grupos migratorios -mayoritariamente europeos- han incidido fuertemente en el proceso de formación de los incentivos locales para el desarrollo.La ponencia explora estos grandes tópicos con el fin de efectuar un análisis comparativo con respecto al proceso de formación de los incentivos locales para el desarrollo y de sus resultados.
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Assessing the Dendroclimatological Potential of Polylepis rodolfo-vasquezii in the Tropical Peruvian AndesGunderson, Jeffrey Donald 26 August 2019 (has links)
No description available.
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