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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Écoulements microfluidiques pilotés sans contact par une onde laser

Robert de saint vincent, Matthieu 08 October 2010 (has links)
L’effet thermocapillaire (ou Marangoni) est la résultante mécanique d’un gradient de tensioninterfaciale induit par la présence d’un gradient de température sur une interface fluide. Il semanifeste par (i) la migration d’un objet fini (goutte, bulle) immergé, et (ii) une déflexion del’interface. Sa nature interfaciale le rend particulièrement pertinent à petite échelle, notammenten microfluidique diphasique. Ce travail de thèse montre comment un effet thermocapillaireinduit localement par chauffage laser peut être utilisé pour produire des composants optofluidiquesélémentaires (vanne, aiguillage, échantillonneur), et en présente une étude quantitative.La déstabilisation d’un jet microfluidique forcée par laser, conduisant à sa rupture, est égalementprésentée et caractérisée. Cette « boîte à outils » optique fournit ainsi une approche sans contact,pour produire et manipuler des gouttes en microfluidique digitale sans nécessité d’une microfabricationdédiée. Par ailleurs, afin de caractériser sur des temps longs les gouttes produites,et ainsi considérer des populations statistiquement significatives, un dispositif optoélectroniquesimple pour mesurer les gouttes et leur vitesse en temps réel a également été développé. / The thermocapillary (or Marangoni) effect is the mechanical result of an interfacial tension gradientinduced by a temperature gradient on a fluid interface. This effect manifests itself byinducing (i) the migration of an immersed finite-size object (droplet, bubble), and (ii) a deflexionof the interface. Due to its interfacial nature, the Marangoni effect is particularly relevantat small length scales, especially in the context of two-phase microfluidics. This thesis aims atapplying the thermocapillary effect locally induced by laser heating, in order to create some basicoptofluidic actuators (valve, switch, sampler). A quantitative study of these actuators is presented.The laser-forced destabilization of a co-flowing microfluidic jet, leading to its breakup,is also investigated. This “optical toolbox” represents a non-contacting, and microfabricationfreeapproach for the production and handling of droplets in digital microfluidics. Moreover, tocharacterize these droplet over long times, thus considering statistically significant populations,a simple optoelectronic device has been developed for measuring the size and velocity of thedroplets in real time.
252

Les déterminants de la performance du vendeur en situation de plateau de carrière / The performance determinants of the plateaued salesperson

Perotto, François 21 June 2011 (has links)
Les déterminants de la performance du vendeur ont fait l’objet d’un vaste courant de recherche dont il ressort que les variables personnelles sont les plus explicatives de la variation de la performance. Parallèlement, la recherche sur le plateau de carrière du vendeur qui est encore peu développée, propose des actions visant à éviter le plateau.Cette recherche propose un modèle structurel de déterminants de la performance du vendeur fondés sur certains traits de personnalité : l’esprit de compétition, la rigueur, l’estime de soi et l’efficacité personnelle et analyse les relations entre ces traits entre eux et entre l’effort et la performance. Cette recherche précise également la modération du plateau de carrière sur certaines variables du modèle.Il ressort de cette recherche la validation d’un modèle conceptuel de déterminants de la performance du vendeur fondé sur les traits de personnalité et, de la modération positive et faible du plateau de carrière sur les liens entre l’esprit de compétition, la rigueur et l’effort et,la performance, qui forment ces traits de personnalité.Cette étude met en lumière le rôle d’une triade composée de l’efficacité personnelle, de l’effort et de la rigueur comme variables explicatives de la performance des vendeurs performants. Une autre caractéristique des vendeurs performants concerne l’orientation deleurs efforts dirigés en efforts habiles, avec un haut niveau d’effort qui tend à devenir unenorme de travail pour les vendeurs performants expérimentés. Au contraire, les vendeursstandards ont une direction de leurs efforts moins habile.Une autre caractéristique des vendeurs performants concerne l’efficacité personnelle et leurcapacité à analyser leurs expériences d’abord passées puis présentes pour déterminer leurs expériences actives de maîtrise. Les vendeurs performants sont rigoureux et, tout en restant centré sur l’objectif à atteindre, savent analyser la situation et adapter les actions et les moyens à mettre en oeuvre pour l’atteindre. Enfin, l’esprit de compétition agit en catalyseur de cette triade efficacité personnelle-effort-rigueur. Pour les vendeurs performants de 45 ans et moins, l’effort et l’efficacité personnelle sont deux variables essentielles et le relais est pris ensuite, au-delà de 45 ans par la rigueur et l’esprit de compétition.Le plateau de carrière des vendeurs performants est un plateau accepté notamment parce qu’ils vivent un enrichissement du poste. Cet enrichissement du poste est la conséquence du stress dans le rôle et des expériences positives. / The research on the performance determinants of the salesperson has been widely studied and it appears that the variation on performance is mostly due to personal variables.The research on the salesperson plateau is less studied and aims mainly at actions to avoid plateauing.This research proposes a structural model on the performance determinants of salesperson based on personality traits: competitiveness, conscientiousness, self-esteem and self-efficacy,and analyses the relationships between these traits among them, and between effort and performance. This research points out as well the weak moderating effect of the plateau on the variables of the model.A conceptual model on the performance determinants of the salesperson is validated and, theweak positive moderating effect of the plateau on the structural path between competitiveness,conscientiousness, effort and performance is confirmed.This study points out the role of a triad made of self-efficacy, effort and conscientiousness a sexplaining variables of the performance of performing salespeople. Another characteristic of aperforming salesperson regards their effort which is smart, and their high level of effort becomes normative for senior performing salespersons. To the contrary, average performing salespersons have a less smart effort and a more hard effort.Another characteristic of performing salespersons regards self-efficacy and their ability inanalyzing their experiences firstly past experiences, and then present experiences in order todetermine their enactive mastery. Performing salespersons are conscientious and whileremaining focused on the objective, they analyze the situation and adapt their actions and means to reach the objective. Competitiveness is a catalyzer of the triad self-efficacy-effort conscientiousness.For performing salespersons of age ≤ 45, effort and self-efficacy are the main drivers and then, after the age 45, conscientiousness and competitiveness become the main drivers.The career plateau of performing salespersons is accepted in particular because they experience job enrichment, and this job enrichment is a consequence of the role stress and positive experiences.
253

Analyse technologique et techno-fonctionnelle comparative des faciès moustériens des bordure est et sud de la mer Caspienne / Comparative technological and techno-functional analysis of the Mousterian facies of the eastern and southern Caspian Sea / تجزیه و تحلیل فن آوری و فنی : رخساره های موسترین در شرق و جنوب دریای خزر کاربردی

Jamialahmadi, Mana 17 December 2018 (has links)
L’Asie du sud-ouest et en particulier le plateau iranien, au croisement de l’Afrique, de l’Europe et de l’Asie, constituent une région assez unique marquée par une histoire longue et diversifiée. Cet espace a souvent été considérée au Paléolithique moyen comme un lieu de passage d’hommes anatomiquement différents : Homo Sapiens et Neandertal. Mais pour plusieurs raisons, les chercheurs ont concentré leurs recherches sur la région du Levant et du Zagros. Le sud et l’est du pourtour de la Mer Caspienne sont en revanche nettement moins étudiés. Si le Moustérien du Proche-Orient est marqué par la prédominance de débitages de type Levallois, au-delà du Torus à l’ouest de la Caspienne, c'est-à-dire en Azerbaïdjan et en Géorgie, les industries lithiques se caractérisent par des pièces bifaciales dites micoquiennes. Dans ce contexte, que se passe-t-il à l'est et sud de la mer Caspienne entre ces deux grandes aires d’influence ? Une étude approfondie des outillages lithiques par une approche technologique et technofonctionnelle a été menée sur cinq assemblages d’Iran et du Turkménistan. Nous avons pu observer que si à l’est de la mer Caspienne la tradition bifaciale est bien attestée dans certaines industries turkmènes, elle regroupe des systèmes techniques variés. Ces éléments nous invitent donc à faire le lien avec d’autres « techno-complexes » jusqu’à présent moins connus. Il semblerait donc que le Turkménistan et l'est de l'Iran représentent un carrefour où différents complexes techniques ont pu se rencontrer. Cette diversité de systèmes techniques semble indiquer une complexité plus importante qu’attendue des dynamiques de peuplements pendant le Moustérien. C’est grâce à la mise en évidence de la variabilité technique que l’on tentera de percevoir et de reconstituer cesphénomènes de peuplements et la mobilité des groupes humains préhistoriques dans les espaces qu’ils ont occupés. / Southwest Asia and in particular the Iranian plateau, at the crossroads of Africa, Europe and Asia, constitute a rather unique area with a long and diversified history. In Middle Paleolithic, the whole region has often been considered as a place for passage of anatomically different humans: Homo Sapiens and Neanderthal. However, for several reasons, researchers focused their activities, on the region of Levant and Zagros, therefore the southern parts and the east of Caspian Sea are much less studied. As Mousterian of the near east region is marked by the predominance of Levalloisdebitages, in Torus region (regions in the west of Caspian Sea including current Azerbaijan and Georgia), the lithic industries are characterized by so-called Micoquian bifacial pieces. In this context, a very important question is what happened in the east and the south of Caspian Sea,between these two great areas of influence.A deep study of lithic tools has been conducted on five assemblages of Iran andTurkmenistan, by a technological and techno-functional approach. The obtained results show that if in the east of Caspian Sea the bifacial tradition is well attested in some Turkmen industries, it attests various technical systems. These elements lead us to make the link with the other "techno-complexes" so far less known. It would seem, therefore, that Turkmenistan and eastern Iran represent a crossroads where different techno-complexes could meet.This diversity of technical systems seems to indicate a complexity more than expected of dynamics of populations during Mousterian. Thanks to the demonstration of the technical variation, we will try to perceive and reconstruct these phenomena of populations, the mobility of prehistoric human groups, in the environment that they occupied. / جنوب غرب آسیا و به خصوص فلات ایران، در تقاطع قاره های آفریقا، اروپا و آسیا، منطقه ای نسبتا منحصر به فرد با تاریخی طولانی و متنوع را تشکیل می دهند. در طول دوره پارینه سنگی میانی، این منطقه اغلب به عنوان مکانی برای عبور گونه های مختلف انسان: انسان هوشمند باستانی و نئاندرتال در نظر گرفته شده است. با این حال، به دلایل مختلف، محققان اغلب در انجام فعالیت های علمی خود در منطقه لوانت و زاگرس متمرکز بوده اند بخش های شرقی دریای خزر بسیار کمتر مورد مطالعه قرار گرفته اند.اگر موسترین در منطقه خاورمیانه با تراشه برداری لوالوا عجین شده است، منطقه توروس در غرب دریای خزر (شامل آذربایجان و گرجستان کنونی) با قطعات دو طرفه از نوع میکوکین شناخته می شود. در این زمینه، سوال مهم مطرح این است که چه اتفاقی در شرق و جنوب دریای خزر، بین این دو حوزه بزرگ رخ داده است؟در این راستا، مطالعه ایی بسیار گسترده توسط روش های تجزیه و تحلیلی فن آوری و فنی-کاربردی بر روی ابزارهایی از پنج مجموعه از ایران و ترکمنستان انجام شد. نتایج به دست آمده نشان می دهد که علی رغم حضور ابزارهای دو طرفه در برخی از صنایع ترکمنستان، در شرق دریای خزر شاهد سیستم های تکنیکی متفاوتی هستیم. این عناصر ما را بر آن می دارد که به دنبال ارتباط آنها با سیستم های فنی ای باشیم که تا کنون کمتر شناخته شده اند. به نظر می رسد که ترکمنستان و مناطق شرقی ایران، محل تقاطع سیستم های فنی مختلفی باشند.این تنوع در سیستم های فنی احتمالا از آنچه پیشتر در مورد پویایی جمعیت در طول دوره موسترین تصور می شد بسیار پیچیده تر باشد. به لطف شناسایی این گوناگونی های فنی است که ما سعی می کنیم پدیده های مربوط به جمعیت و جابجایی گروه های انسانی پیش از تاریخ در محیط مورد اشغال آنها را درک و بازسازی کنیم.
254

Etude pétro-chronologique de la chaîne des Longmen Shan (Tibet oriental) : héritage géologique et implications pour la géodynamique actuelle / A petro-chronological study of the Longmen Shan thrust belt (eastern Tibet) : geological inheritance and implication for the present geodynamics

Airaghi, Laura 27 October 2017 (has links)
Un des enjeux majeurs en Sciences de la Terre est la compréhension des mécanismes de déformation de la lithosphère continentale dans des zones de convergence. Le plateau Tibétain constitue un laboratoire naturel idéal pour l'étude des processus crustaux profonds actifs dans ces contextes, du fait de sa superficie et de son altitude remarquables. Le soulèvement et l'épaississement de la croûte Tibétaine ont été classiquement attribués aux effets de la collision Inde-Asie Tertiaire. Cependant, cette interprétation a été récemment mise en question par une série d’observations géologiques et géophysiques non concordantes, à différents endroits du plateau.L'objectif de cette thèse est de quantifier l’importance de l’héritage géologique dans la déformation à long-terme et à court-terme d’une chaîne active, en déchiffrant les différentes étapes de la structuration des Longmen Shan, la bordure la plus énigmatique du plateau Tibétain. Dans la chaîne des Longmen Shan la croûte Tibétaine est très épaissie (>60 km) et l'activité tectonique est localisée le long des failles d’échelle lithosphérique, comme démontré par les séismes de Wenchuan 2008 (Mw 7.9) et de Lushan 2013 (Mw 6.6). Un fort gradient topographique est présent, bien que les taux de convergence mesurés par GPS soient très faibles (<3 mm/an). Ces caractéristiques ne sont pas explicables par un modèle unique de déformation crustale, ce qui suggère une forte contribution de l'héritage géologique acquis avant la collision Inde-Asie dans la structure actuelle de la chaîne.Une étude pétro-chronologique qui combine des observations microstructurales avec la cartographie chimique des minéraux majeurs et accessoires, la modélisation thermodynamique et la datation in-situ par méthode 40Ar/39Ar et U-Pb/Th sur mica et allanite a été appliquée aux roches métamorphique à l’affleurement de chaque côté des faille majeures. L’analyse haute résolution montre que les minéraux métamorphiques dans la matrice des sédiments à grenat provenant des unités internes de la chaîne préservent dans leur composition le témoignage de différentes étapes du métamorphisme. Ceci s’explique par un rééquilibrage chimique incomplet en raison de la variabilité des fluides disponibles au cours du métamorphisme. Les différentes étapes du métamorphisme sont aussi enregistrées dans le signal 40Ar/39Ar des micas et dans la composition des minéraux accessoires.La compréhension des processus pétrologiques à petite échelle a été intégrée aux observations de terrain afin de quantifier l’épaississement de la croûte Tibétaine au Mésozoïque (> 30 km) et de mettre en évidence un saut métamorphique >150°C à travers les failles majeures, hérité de la tectonique Mésozoïque. Si les unités internes de la chaîne ont été fortement déformées, découplées du socle cristallin et métamorphisées à T ~580-600°C (P ~11 kbar), les unités externes apparaissent moins déformées et épaissies (T< 400°C, P< 5 kbar). Une exhumation partielle du socle depuis c. 20 km de profondeur a été également documentée à 120-140 Ma et reliée à un évènement tectonique méconnu auparavant.Cette thèse a ainsi permis de quantifier la durée et les conditions qui caractérisent les différentes étapes de la maturation de la chaîne: les unités internes atteignent la relaxation thermique 40 Ma après le début de la propagation du prisme orogénique. Le socle est réactivé 40 Ma plus tard, lorsqu’il atteint des conditions thermiques proches de celles de sa couverture sédimentaire. L’héritage géologique Mésozoïque contrôle fortement l’état thermique et rhéologique de la croûte supérieure au moment de la réactivation Cénozoïque ainsi que la structure actuelle de la chaîne.L’étude petro-chronologique de différents segments de la chaîne a aussi mis en évidence une segmentation métamorphique héritée du Mésozoïque qui correspond à la segmentation actuelle des failles. Ceci suggère que des structures héritées pourraient en partie contrôler la localisation des séismes récents. / One of the major challenges in Earth Sciences is understanding how the continental lithosphere deforms in convergent settings, according to which timescales. For its elevation and extension the Tibetan plateau is an ideal natural laboratory for the study of deep crustal processes in active convergent settings. The rise and thickening of the Tibetan plateau has generally been related to the only collision between the Eurasian and Indian plates during the Cenozoic. However, this interpretation has been recently put into question by apparently contrasting geophysical and geological features observed at different locations on the plateau.The aim of this PhD is to quantify the importance of the geological inheritance in the long-term and short-term deformation of an active thrust belt, focusing on the Longmen Shan orogen, the most enigmatic border of the Tibetan plateau. In the Longmen Shan (eastern Tibet) the Tibetan crust is over thickened (>60 km), the tectonic activity is localized along lithospheric faults -as demonstrated by the occurrence of the Mw 7.9 Wenchuan (2008) and Mw 6.6 Lushan (2013) earthquakes- and a high topography survives despite low convergence rates measured by GPS (<3 mm/yr). These observations are hardly reconcilable in a unique model of crustal deformation, suggesting a contribution of the geological inheritance from the geological history preceding the India-Asia collision.A petro-chronological approach that combines microstructural observations, compositional mapping of major and accessory mineral phases, thermodynamic modelling, in-situ 40Ar/39Ar dating, Ar diffusion modelling and in-situ U/Pb-Th allanite dating was applied to metamorphic rocks on each side of the major faults that strike parallel to the belt. This high-resolution study shows that in garnet-bearing rocks of the internal units of the belt matrix minerals record different stages of the metamorphic path in their composition. This is due to an incomplete chemical re-equilibration explained by a variable fluid availability during metamorphism. Different stages of metamorphism and fluid-assisted reactions sequences are also recorded in the 40Ar/39Ar signal of micas and in the composition and textures of the accessory phases.The understanding of petrological processes at the small scale was combined with field observations to quantify the Mesozoic thickness of the Tibetan crust at > 30 km and to unravel a metamorphic jump of greater than 150°C across the major faults, inherited from the Mesozoic tectonics. While internal units of the belt were strongly deformed, decoupled from the basement and metamorphosed at T ~ 580-600°C (P ~11 kbar), external units were less deformed and experienced lower temperatures conditions (T < 400°C, P < 5 kbar). The partial exhumation of the crystalline basement from c. 20 km depth along the major fault (in both internal and external units) occurred at c. 120-140 Ma during a previously poorly documented tectonic event.The multi-method approach applied on a wide geographical area and on a large time interval enabled to quantify the rates and conditions of the different stages of the maturation of the belt; internal units reached the thermal relaxation at ~600°C 40 Ma after the beginning of the propagation of the orogenic load. The basement was re-activated 40 Ma later, at similar thermal conditions than its sedimentary cover. The Mesozoic geological inheritance is therefore a key element in the present structure of the belt and strongly controlled the rheological and structural state of the upper crust at the moment of the Cenozoic re-activation.The petro-chronological study of different segments of the belt showed an along-strike metamorphic segmentation of the Longmen Shan inherited from the Mesozoic. This segmentation corresponds to the present fault segmentation, underlying the potential role of inherited structure in controlling the geographic distribution of the recent earthquakes.
255

Human and livestock faecal biomarkers at the prehistorical encampment site of Ullafelsen in the Fotsch Valley, Stubai Alps, Austria – potential and limitations

Lerch, Marcel, Bromm, Tobias, Geitner, Clemens, Haas, Jean Nicolas, Schäfer, Dieter, Glaser, Bruno, Zech, Michael 30 May 2024 (has links)
The Ullafelsen at 1869 m above sea level (a.s.l.) in the Tyrolean Stubai Alps next to Innsbruck is an important (geo)archeological reference site for the Mesolithic period. Buried fireplaces on the Ullafelsen plateau were dated at 10.9 to 9.5 ka cal BP and demonstrate together with thousands of flint stone artifacts the presence of hunter-gatherers during the Early Holocene. Grazing livestock has been a predominant anthropozoological impact in the Fotsch Valley presumably since the Bronze Age (4.2–2.8 ka). In order to study the human and/or livestock faeces input on the Ullafelsen, we carried out steroid analyses on 2 modern ruminant faeces samples from cattle and sheep, 37 soil samples from seven archeological soil profiles, and 9 soil samples from five non-archeological soil profiles from the Fotsch Valley used as reference sites. The dominance of 5β-stigmastanol and deoxycholic acid in modern cattle and sheep faeces can be used as markers for the input of ruminant faeces in soils. The OAh horizons, which have accumulated and developed since the Mesolithic, revealed high contents of steroids (sterols, stanols, stanones and bile acids); the eluvial light layer (E (LL)) horizon coinciding with the Mesolithic living floor is characterized by medium contents of steroids. By contrast, the subsoil horizons Bh, Bs and BvCv contain low contents of faecal biomarkers, indicating that leaching of steroids into the podsolic subsoils is not an important factor. High content of 5β-stigmastanol and deoxycholic acid in all soil samples gives evidence for faeces input of ruminants. The steroid patterns and ratios indicate a negligible input of human faeces on the Ullafelsen. In conclusion, our results reflect a strong faeces input by livestock, rather than by humans as found for other Anthrosols such as Amazonian dark earths. Further studies need to focus on the question of the exact timing of faeces deposition.
256

Enjeux autour de l'énergie électrique éolienne en Ardèche.<br />La construction sociale du plateau de Saint-Agrève

Gueorguieva-Faye, Diana 05 June 2007 (has links) (PDF)
Après la ratification en l'année 2001 de la Directive européenne sur les énergies renouvelables la France se retrouve dans une période d'ajustements juridiques et administratifs de sa politique énergétique concernant l'énergie du vent. On observe une réaction d'opposition souvent violente de la part des futurs riverains des parcs éoliens avec la mise en avant des problèmes environnementaux et de démocratie.<br />L'approche anthropologique est ici utilisée pour analyser la construction de l'acceptabilité sociale des éoliennes et la contradiction paysage/énergie/environnement au sein même des mouvements écologistes. L'étude de terrain sur le plateau de Saint-Agrève montre que l'identité locale peut aujourd'hui se construire autour d'un projet commun, un projet de production énergétique.
257

Geohistory of the Central Anatolian Plateau southern margin (southern Turkey)

Radeff, Giuditta January 2014 (has links)
The Adana Basin of southern Turkey, situated at the SE margin of the Central Anatolian Plateau is ideally located to record Neogene topographic and tectonic changes in the easternmost Mediterranean realm. Using industry seismic reflection data we correlate 34 seismic profiles with corresponding exposed units in the Adana Basin. The time-depth conversion of the interpreted seismic profiles allows us to reconstruct the subsidence curve of the Adana Basin and to outline the occurrence of a major increase in both subsidence and sedimentation rates at 5.45 – 5.33 Ma, leading to the deposition of almost 1500 km3 of conglomerates and marls. Our provenance analysis of the conglomerates reveals that most of the sediment is derived from and north of the SE margin of the Central Anatolian Plateau. A comparison of these results with the composition of recent conglomerates and the present drainage basins indicates major changes between late Messinian and present-day source areas. We suggest that these changes in source areas result of uplift and ensuing erosion of the SE margin of the plateau. This hypothesis is supported by the comparison of the Adana Basin subsidence curve with the subsidence curve of the Mut Basin, a mainly Neogene basin located on top of the Central Anatolian Plateau southern margin, showing that the Adana Basin subsidence event is coeval with an uplift episode of the plateau southern margin. The collection of several fault measurements in the Adana region show different deformation styles for the NW and SE margins of the Adana Basin. The weakly seismic NW portion of the basin is characterized by extensional and transtensional structures cutting Neogene deposits, likely accomodating the differential uplift occurring between the basin and the SE margin of the plateau. We interpret the tectonic evolution of the southern flank of the Central Anatolian Plateau and the coeval subsidence and sedimentation in the Adana Basin to be related to deep lithospheric processes, particularly lithospheric delamination and slab break-off. / Il Bacino di Adana (Turchia meridionale) é situato in posizione esterna rispetto al margine sud-orientale del plateau anatolico centrale. Il bacino risulta ubicato in posizione strategica per registrare i principali cambiamenti della topografia e dell’assetto tettonico avvenuti durante il Neogene nel Mediterraneo orientale. Utilizzando dati sismici provenienti dall’industria petrolifera abbiamo correlato 34 profili sismici con le unitá corrispondenti affioranti nel Bacino di Adana. La conversione da tempi a profonditá dei profili sismici interpretati ci ha permesso di ricostruire la curva di subsidenza del Bacino di Adana e di individuare un evento caratterizato da un importante aumento della subsidenza associato ad un considerevole incremento del tasso di sedimentazione. Questo evento, avvenuto tra 5.45 e 5.33 Ma ha portato alla deposizione di quasi 1500 km3 di conglomerati e marne. La nostra analisi di provenienza della porzione conglomeratica mostra che la maggior parte del sedimento proviene dal margine sud-orientale del plateau anatolico centrale e dalle aree situate a nord di questo. La comparazione di questi risultati con la composizione litologica di conglomerati recenti e con le litologie affioranti nei bacini di drenaggio attuali mostra cambiamenti rilevanti tra le aree di provenienza del sedimento Messiniane e quelle attuali. Riteniamo che questi cambiamenti nelle aree sorgente siano il risultato del sollevamento e della successiva erosione del margine sud-orientale del plateau anatolico centrale. Questa ipotesi é supportata dal confronto delle curve di subsidenza del Bacino di Adana e del Bacino di Mut, un bacino principalmente neogenico situato sulla sommitá del margine meridionale del plateau. La comparazione delle due curve di subsidenza mostra che l’evento di forte subsidenza del Bacino di Adana é coevo ad un episodio di sollevamento del margine meridionale del plateau anatolico centrale. La raccolta di un fitto dataset strutturale acquisito nella regione di Adana mostra differenti stili deformativi per i margini nord-occidentale e sud-orientale del bacino. La porzione nord-occidentale del bacino, debolmente sismica, é caratterizzata da strutture estensionali e transtensive che tagliano I depositi neogenici, verosimilmente accomodando il sollevamento differenziale tra il bacino e il margine sud-orientale del plateau. Riteniamo che l’evoluzione tettonica del margine meridionale del plateau anatolico centrale e la contemporanea subsidenza e sedimentazione nel Bacino di Adana sia da ricondurre a processi litosferici profondi, in particolar modo delaminazione litosferica e slab break-off.
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High-frequency tectonic sequences in the Campanian Castlegate Formation during a transition from the Sevier to Laramide orogeny, Utah, U.S.A.

Cross, David B 13 May 2016 (has links)
Though stratigraphic correlations are abundant in the Cordilleran basin-fill, they rarely include along-strike transects providing a spatio-temporal sense of deformation, sediment-supply and subsidence. A new, high-resolution, regional strike-correlation of the Castlegate Formation reveals progressive northward-growth of the San Rafael Swell during two embryonic episodes of Laramide-style deformation in central Utah. The intrabasinal deformation-events produced gentle lithospheric-folding punctuated by erosional-truncation of upwarped regions. The earliest episode occurred at 78 Ma in the southern San Rafael Swell likely causing soft-sediment deformation and stratal-tilting. Following this the alluvial-plain was leveled and rapid, extensive-progradation took place. A second episode, at 75 Ma, where deformation was focused in the northern San Rafael Swell, also caused sediment-liquefaction and erosional beveling. The stratal-tilting and sediment-liquefaction is attributed to seismicity induced by basal-traction between a subducting flat-slab and continental-lithosphere. The south-to north time-transgression of uplift is spatio-temporally consistent with NE-propagation of an oceanic-plateau subducted shallowly beneath the region.
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Estudo arqueológico no alto vale do rio Ribeira: área do Gasoduto Bolívia-Brasil, trecho X, Paraná / Archaeological study in the upper valley of Ribeira river: place of Bolívia-Brazil gas pipeline segment X, Paraná.

Parellada, Claudia Inês 07 March 2006 (has links)
No alto vale do Ribeira e na margem esquerda do Itapirapuã, em área paranaense, houve pouca pesquisa arqueológica, assim a implantação do programa de salvamento do Gasoduto Bolívia-Brasil(Gasbol), naquela região, permitiu a possibilidade de um estudo que trouxesse dados inéditos e importantes para a compreensão do processo de ocupação humana da porção setentrional do leste paranaense. Prospectou-se através de grandes transects, ao longo do segmento estudado, e apesar das limitações de tempo e da análise realizar-se apenas em trajetórias lineares ao longo do duto, puderam ser reveladas novas informações regionais e aspectos sobre a arqueologia da paisagem. Analisaram-se, especialmente, quatro conjuntos de concentração de sítios Itararé-Taquara: Fazenda Marrecas, Bomba, São Sebastião, e Morro Grande, implantados nos mais variados compartimentos topográficos, inclusive cristas de morros. Assim, nesse trabalho, faz-se a análise e discussão sobre a distribuição e implantação de sítios arqueológicos ao longo do traçado do Gasbol, e os vestígios recuperados, inclusive as pinturas rupestres de um abrigo granítico, dado inédito na região, identificado nas prospecções de campo. Analisa-se a arqueologia musealizada no Paraná e são relacionadas medidas para a conservação do patrimônio arqueológico das áreas atingidas pelo empreendimento. / Few archaeological research was known in the upper valley of Ribeira river and Itapirapuã left edge, on Paraná side, thus the Survey Program of Bolivia-Brazil gas pipeline allowed this study, which bring new and important data to the knowledge of human occupation process of the northern portion of Paraná east. The region was studied by big transects, along the section, and beside the short time and the kind of analysis, that surveyed only lineal course, it was possible to reveal new regional information and aspects of landscape archaeology. Four areas, with many Itararé-Taquara sites, were researched, in a special way: Fazenda Marrecas, Bomba, São Sebastião e Morro Grande, that were located in a big variety of topographic conditions, inclusively on the top of the hills. In this research, we studied and discussed the distribution and the location of archaeological sites, along of the pipeline way, and the material, inclusively the rock art of a granite shelter, a new one in this region, identified in this research. The Paraná museal archaeology was discussed and recommendations for archaeological resource protection, of this area, are presented.
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Vulnerabilidade do carste nas cabeceiras dos Rios das Almas, São José de Guapiara (Bacia do Rio Paranapanema) e do Rio Pilões (Bacia do Rio Ribeira de Iguape) na região do Parque Estadual Invervales (PEI), Estado de São Paulo / not available

Lenhare, Bruno Daniel 10 June 2014 (has links)
Entre o Planalto de Guapiara e a Serra de Paranapiacaba ocorrem sistemas cársticos que estão sob constante pressão do avanço antrópicodas mais variadas naturezas, como mineração de rochas carbonáticas, silviculturas, agriculturas e a própria ocupação humana. Este estudo apresenta primeiramente um levantamento detalhado de aspectos geológicos e geomorfológicos do carste da região, baseado em fotointerpretação, geoprocessamento e trabalhos de campo. Os sistemas cársticos se desenvolvem de forma distinta em ambos os compartimentos geomorfológicos. No Planalto de Guapiara o carste é pouco expressivo com feições cársticas dispersas e raras em todos os corpos carbonáticos abordados. O relevo mais suavizado, com gradientes hidráulicos relativamente baixos e o pouco tempo de exposição das rochas carbonáticas não permitiram o desenvolvimento de umsistema cárstico pleno no planalto. Na Serra de Paranapiacaba, o relevo mais acidentado, associado a altos gradientes hidráulicos, carbonatos mais puros, e maior tempo de exposição das rochas carbonáticas, permite que as feições sejam mais concentradas e apresentem maior desenvolvimento em relação ao planalto. A partir dadeterminação da configuração do carste foi possível se determinar a vulnerabilidadee a delimitação de um zoneamento ambiental do sistema cárstico com a utilização de dois métodos: EPIK e KDI. Na região do Planalto de Guapiara a vulnerabilidade do carsteé baixa e a ocupação humana é mais expressiva, com poucos riscos ao sistema e à população que ali se estabeleceu. Na região da Serra de Paranapiacaba a presença de feições cársticas mais constantes e mais concentradas indica vulnerabilidade muito alta, porém a presença de Unidades de Conservação garante a preservação deste tipo de sistema e a baixa ocupação e interferência humana. Espera-se que este estudo venha a contribuir para políticas públicas de ordenamento territorial futuro, minimizando os eventuais impactos no carste da região. / Between the Guapiara Plateau and the Paranapiacaba Range there are karst systems that are under constant pressure from anthropic advancement of various natures, such as mining of carbonate rocks, forestry, agricultureand human settlement itself. This study presents a detailed survey of geologic and geomorphologic aspects based on photo interpretation, GIS and fieldwork observations. Karst systems develop differently in both geomorphological compartments. At the Guapiara Plateau is not very expressive with scattered and rare karst features in all carbonate bodies covered by this study. The most cushioned relief, with relatively low hydraulic gradients and the short time of exposure of the carbonate rocks did not allow the full development of a karst system at the plateau. At Paranapiacaba Range, the most rugged relief, associated with high hydraulic gradients, purer carbonates and longer exposure of the carbonate rocks, allows karst features to be more concentrated and greater development in relation to the plateau. From the determination of the karst setting was possible to determine the vulnerability and delimitation of an environmental zoning of karst system using two methods: EPIK and KDI. At the Guapiara Plateau the karst vulnerability is low and human settlement is more expressive, with little risk to the system and the people who settled there. At Paranapiacaba Range the presence of karst features is more constant and more concentrated so the vulnerability is very high, but the presence of protected areas to guarantee the preservation of this type ofsystem and the low occupancy and human interference . It is hoped that this study will contribute to public policies for future land use, minimizing any impacts on the karst region.

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