• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 1
  • 1
  • Tagged with
  • 9
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 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.
1

Metal biogeochemistry of a mine contaminated estuarine-coastal system in SW Spain

Braungardt, Charlotte Barbara January 2000 (has links)
The aim of this project was to investigate the biogeochemistry and transport of metals in a river/estuarine system contaminated by acid mine drainage. The Rio Tinto and Rio Odiel drain a metalliferous mining area in the Iberian Pyrite Belt in the south-west of Spain. The pH values in the rivers were low (< 3) and dissolved metal concentrations were . extremely high, up to 2.6 mM Zn, 860 \M Cu, 6.0 jaM Cd and 72 nM U . The seasonal cycle of low precipitation and flash floods was identified as an important factor in generating the more severe contamination of the rivers with Fe, A l , Mn, Zn, Cu, N i , Co and Cd observed during autumn and winter, compared to spring and summer. The estuarine behaviour of dissolved Fe, Mn, Zn, Cu, N i , Co and Cd was primarily = controlled by pH. Apart from an addition of these metals from the sediment in the upper Tinto estuary, conservative mixing was observed up to pH ~ 5 (at S ~ 30), above which Fe, Mn, Zn, Cu, N i and Co were removed from solution. Voltammetric speciation studies showed that Cu complexing organic ligands (logK'cuL ~ 11-5, CL = 32 - 199 nM) in the estuary were saturated, and thermodynamic calculations indicated that the concentration of Cu^"^ reached values (pCu^"^ < 9) that are toxic to some marine and estuarine organisms. The estimation of fluxes indicated that the dissolved metal export from this system to thecoastal zone averages 101 d'^ Zn, 2.3 t d"' Cu, 180 kg d"^ N i and 236 kg d"^ Co, with higher contributions during wet, compared to the dry seasons. On-line measurements of Zn, Cu and N i in the Gulf of Cadiz revealed metal plumes associated with the Tinto/Odiel system and the Guadiana and Guadalquivir rivers. As a result of entrainment by the Atlantic Ocean surface current flowing into the Mediterranean Sea, the metal contamination in waters of the Gulf of Cadiz is transported south and eastward.
2

Les Conséquences médicales du naufrage de l'Amoco-Cadiz.

Morizur, Alain, January 1900 (has links)
Th.--Méd.--Brest, 1980. N°: 497.
3

Märk-wärdige händelser : En svensk konsuls brev till kanslikollegium 1773-1800 / Noteworthy events

Skagerstrand, Benjamin January 2019 (has links)
No description available.
4

Scottish commercial contacts with the Iberian world, 1581-1730

McLoughlin, Claire January 2014 (has links)
This thesis analyses the commercial relations between Scotland and the geo-political area known as the Iberian world in the early modern period. Despite being geographically one of the largest areas of Europe, as well as arguably the politically most weighty, there has, until this thesis, been no scholarly research on Scottish trade relations with this area. Though the archives suggest regular and sustained contact, very little is known about Scottish-Iberian connections beyond the overtly political. When compared to northern Europe the region of Iberia and its dominions differed significantly, not only due to a different branch of Christianity being practised there but also due to the influence of the Habsburg empire and the power it was perceived to give the Spanish Habsburgs. Looking predominantly at Scottish commercial contacts with Spain, the Spanish Netherlands and Portugal, this project considers a number of angles such as England's impact on Scottish commercial relations with Iberia. For example, very little would be known about Scottish commercial relations with Iberia in the late-sixteenth century if it were not for the Anglo-Spanish war of that period. The central role of conflict in Scottish-Iberian relations continues into the seventeenth century, with the Cromwellian/Stuart struggles with the Dutch Republic and later disputes between the new state of Great Britain and Habsburg Spain all affecting trade. This thesis demonstrates the important role of triangular and entrepôt trade, which was popular with Scottish merchants who wished to obtain Iberian goods without the risks of sailing into North African corsair territory. Scots did not merely pick up Iberian goods from the entrepôt markets of London and the Dutch Republic they also organised trade to Iberia and its dominions via other Scots, providing evidence of a complex trade network. Further, this thesis has sought to ascertain that, despite the lack of a large Scottish community such as those seen in Poland-Lithuania and Scandinavia, Scottish commercial relations with Iberia were valuable both to the Scottish economy and its merchants. This thesis which continues the work of the Scotland and the Wider World Project, addresses a lack of scholarly work regarding Scottish commercial connections with this key geo-political area.
5

Interactions climatiques et hydrologiques du système Méditerranée/Atlantique au Quaternaire

Penaud, Aurélie 04 December 2009 (has links)
Tandis que la variabilité climatique à long terme du Quaternaire terminal (oscillations glaciaire/interglaciaire) est relativement bien appréhendée aujourd’hui, l'origine et la modalité des variations climatiques haute-fréquence séculaires à millénaires, depuis la très haute fréquence des cycles de Dansgaard-Oeschger (D/O) jusqu'à la plus grande périodicité des événements d'Heinrich, restent toujours matière à débat. Parmi les éléments encore équivoques se trouvent notamment les modalités de transferts de chaleur méridiens et latitudinaux. A ce titre, la connexion hydrologique entre l’Atlantique et la Méditerranée apparaît comme un exemple d’étude particulièrement approprié vu qu’elle illustre le couplage de phénomènes jouant selon un double gradient Est-Ouest et Nord-Sud, reliant ainsi processus subtropicaux et nord atlantiques. Nous avons ainsi ciblé nos analyses sur des séquences prélevées autour du détroit de Gibraltar, avec pour objectif d’étendre les connaissances spatiales et temporelles de la variabilité climatique haute fréquence des derniers 50 000 ans dans le secteur de l’Atlantique Est subtropical et de la Méditerranée occidentale. La méthodologie de cette thèse est ainsi basée sur une comparaison multi-proxies qui inclut des analyses micropaléontologiques (dinokystes et foraminifères planctoniques) et géochimiques (isotopes stables et alkénones). Nous avons ainsi pu tester la cohérence des changements hydrologiques de surface inter- et intra-bassins et tenter de caractériser la migration des fronts hydrologiques associés. Grâce aux sites des marges marocaine et portugaise, notamment, nous avons pu vérifier l’impact des cycles de D/O sur la variabilité de l’intensité des cellules d’upwelling côtières dans ce secteur et sur la dynamique de la veine d’eau méditerranéenne profonde (MOW), couplant signaux des masses d’eau superficielles (température, salinité et productivité) aux paléo-intensités de la MOW. / While the long-term climatic variability of the Quaternary is relatively well understood today, the causes and processes at the origin of the rapid and brutal climatic variability that characterized the last glacial period (Dansgaard-Oeschger cycles), including meridional and latitudinal heat transfer mechanisms, are still subject to debate. As such, studying the hydrological connection between the Atlantic and the Mediterranean Sea appears particularly appropriate since it illustrates the coupling acting on a double East-West and North-South gradient. It furthermore links subtropical processes and North Atlantic ones. We focused our analysis on sedimentary sequences retrieved around the Strait of Gibraltar, in order to extend the spatial and temporal knowledges about the impact of the high frequency climatic variability of the last 50 000 years in the sector of the eastern subtropical Atlantic and of the western Mediterranean Sea. The methodology of this thesis is based on a multi-proxy compilation coupling micropaleontological (dinocysts and planktonic foraminifera) and geochemical (stable isotopes and alkenones) approaches. We have tested the consistency of the sea-surface paleohydrological changes at inter-and intra-basins scales and tried to characterize the associated migration of the hydrological fronts. Sites of the Portuguese and Moroccan margins, in particular, allowed us to document the impact of the D/O cycles on the intensity of coastal upwelling cells as well as on the dynamics of the MOW, by coupling sea surface signals (temperature, salinity and productivity) to paleointensity of the MOW.
6

La sédimentation dans le Golfe de Cadix au cours des derniers 50 000 ans (analyses multi-paramètres et multi-échelles). / The sedimentation of the Gulf of Cadiz in the last 50 000 years (analyses multi - parameters and multi - scales).

Hassan, Rim 10 June 2014 (has links)
La sédimentation dans le Golfe de Cadix, de Gibraltar au Cap Saint-Vincent, est soumise à la circulation d’un flux permanent d’eau profonde venant de la Méditerranée connu sous le nom de Veine d’Eau Méditerranéenne ou VEM. Cette eau plus chaude, plus salée et plus dense que les eaux atlantiques s’écoule sur les marges espagnole et portugaise avec un débit moyen aussi important queplusieurs fleuves du globe. Ce courant de fond entraîne le transport et le remaniement des particules déjà déposées sur le fond. L’étude biostratigraphique détaillée à partir du sens d’enroulement de l’espèce de foraminifère planctonique Globorotalia truncatulinoides, de l’espèce polaire Neogloquadrina pachyderma senestre et du ptéropode Limacina retroversa calibrée par de nombreuses datations 14C AMS et des analyses isotopiques a permis de corréler les carottes. Les variations des processus sédimentaires dans le temps et dans l’espace montrent l’influence du climat sur les variations des taux de sédimentation et la granularité des dépôts. Ainsi, deux périodes de moindre activité de la VEM se situent pendant le Bølling-Alleröd et l’Holocène inférieur. Le Younger Dryas traduit au contraire une période de forte circulation de la VEM. De nombreux hiatus sédimentaires et dépôts gravitaires (glissements, turbidites) traduisent une instabilité sédimentaire liée à la fréquence des tremblements de terre qui se produisent dans le Golfe de Cadix et dans les régions adjacentes. Huit types de traces fossiles ont été reconnus (Chondrites, Diplocraterion, Nereites, Paleophycus, Phycosiphon, Thalassinoides, Zoophycos, des filaments (Trichichnus et Mycelia) et des traces restent indéterminées. Les traces fossiles de Zoophycos et de Paleophycus pendant le LGM traduisent la présence de circulations de masses d’eaux riches en oxygène au niveau du fond. Ces traces fossiles de Zoophycos sont visibles du LGM à l’Holocène inférieur au niveau du chenal-levée de Tasyo. / Sedimentation in the Gulf of Cadiz from Gibraltar Strait to Cape Saint Vincent is submitted to a permanent deep water flux coming from the Mediterranean Sea and called the Mediterranean Outflow Water (MOW). This hotter and saltier water is denser that the Atlantic waters and flows along the Spanish and Portuguese margins with an average discharge as large as the discharge of several world rivers. This bottom current generates the transport and the remolding of already deposited particles. The detailed biostratigraphic study using the coiling direction of planktonic foraminifer species Globorotalia truncatulinoides, of polar specie Neogloquadrina pachyderma sinistral and of pteropod Limacina retroversa and calibrated by numerous 14C AMS dating and stable isotope analysis allowed to correlate sediment cores. Variation of sedimentary processes in time and space shows the impact of climate on sedimentation rates and sediment grain size. Two periods of lesser activity of the MOW are identified during the Bölling-Alleröd and early Holocene. Conversely, the Younger Dryas shows a higher activity of the MOW. Numerous sedimentary hiatuses and mass flow deposits (slumps, turbidites) suggest sedimentary instabilities related to the frequent earthquakes that are initiated in the Gulf of Cadiz and neighboring areas. Height types of fossil traces have been identified (Chondrites, Diplocraterion, Nereites, Paleophycus, Phycosiphon, Thalassinoides, Zoophycos, filaments (Trichichnus and Mycelia) and undetermined traces. Fossil traces of Zoophycos and Paleophycus during the LGM show the activity of oxygen-rich water flowing along the seafloor. Fossil traces of Zoophycos are identified from LGM to lower Holocene in the Tasyo channel-levee.
7

The Phoenician Trade Network: Tracing a Mediterranean Exchange System

Puckett, Neil 1983- 14 March 2013 (has links)
The Phoenicians were known as artisans, merchants, and seafarers by the 10th century B.C.E. They exchanged raw and finished goods with people in many cultural spheres of the ancient world and accumulated wealth in the process. A major factor that aided their success was the establishment of colonies along the Mediterranean and eastern Atlantic coasts. These colonies, established by the eighth century B.C.E., supplied valuable raw materials to the major Phoenician cities in the Levant, while also providing additional markets abroad. Excavations at a myriad of these colonial sites have recovered materials that can be used to identify connections between the colonies, the Levantine cities, and non-Phoenician cultures across the ancient world. By establishing these connections the system of maritime exchange can be better understood and modeled as the Phoenician Trade Network. This network involved both direct and indirect exchange of raw and finished products, people, as well as political and cultural ideas. The colonies were involved in various activities including ceramics production, metallurgy, trade, and agriculture. Native peoples they interacted with provided valuable goods, especially metals, which were sent east to supply the Near Eastern Markets. The Phoenician Trade Network was a system of interconnected, moderately independent population centers which all participated in the advancement of Phoenician mercantilism and wealth. Ultimately, the network collapsed in the sixth century B.C.E. allowing other powers such as the Romans, Carthaginians, and Greeks to replace them as the dominant merchants of the Mediterranean.
8

Comerciantes españoles en los albores del Perú republicano. Entre la persecución y la supervivencia, 1824-1828 / Comerciantes españoles en los albores del Perú republicano. Entre la persecución y la supervivencia, 1824-1828

Ruiz de Gordejuela Urquijo, Jesús 12 April 2018 (has links)
This article discusses how Cadiz merchants conducted their trade with Peru during the transit from colonial to republican times. The basis for describing this brief but intense period is the unpublished correspondence of Francisco de Carranza, a direct witness of the events of that time. As a result of the difficulties that marked those years, merchants increasingly resorted to fraudulent practices like forging invoices or using fake certificates to introduce Spanish goods in Peru. / Este trabajo pretende reflejar cómo vivieron los comerciantes gaditanos con el Perú su ejercicio profesional en el lapso entre la Colonia y la República. Para poder ilustrar en primera persona este breve pero intenso periodo, nos hemos apoyado en la correspondencia inédita del comerciante Francisco de Carranza, testigo directo de los acontecimientos. Asimismo, podemos observar cómo, ante las enormes dificultades que padecieron, estos comerciantes articularon mecanismos fraudulentos como la adulteración de facturas o el uso de falsos certificados para introducir productos españoles en el Perú.
9

Le système contouritique de la marge de l’Algarve : processus sédimentaires et enregistrement au cours du Quaternaire

Marches, Elodie 25 November 2008 (has links)
La marge de l’Algarve est un système contouritique principalement construit par l'action de la Veine d'Eau Méditerranéenne (MOW) et dont l'évolution est fortement influencée par les processus gravitaires, comme l'atteste les nombreux canyons et chenaux qui entaillent la pente continentale. A partir de l’analyse et de l’interprétation de données acoustiques haute résolution, cette thèse propose une reconstruction du fonctionnement du système contouritique de l’Algarve sur l’ensemble du Quaternaire. Ce travail améliore la compréhension des interactions existant entre les processus gravitaires et contouritiques ainsi que les connaissances concernant leurs facteurs de contrôle. Le schéma de circulation actuelle est conforme à la distribution des faciès sédimentaire et à l’architecture des drifts. La morphologie du fond marin, et notamment la présence de canyons, exercent un contrôle important sur l’orientation et l’intensité de la branche supérieure de la MOW (MUW). Les variations spatiales de la circulation océanique, comme celle induite par la capture du courant par un canyon, se traduisent directement par des différences géométriques et morphologiques au sein des dépôts sédimentaires. D’autre part, la présence de paléochenaux sous les drifts révèle l’existence d’un ancien système gravitaire fossilisé par la construction contouritique. La géométrie interne de ces paléochenaux montre que leur évolution temporelle est étroitement liée à l’interaction entre les écoulements gravitaires et l’hydrodynamique régionale. L’étude sismique met en évidence la présence de corps sédimentaires lenticulaires et sableux, intercalés dans les drifts et interprétés comme des « lobes perchés ». La granularité grossière de ces dépôts ainsi que leur fossilisation rapide et leur préservation par la croissance des drifts font de ces corps sédimentaires particuliers de potentiels réservoirs pour les hydrocarbures, et leur confère ainsi un intérêt industriel important. La mise en place des dépôts au cours des deux derniers millions d'années révèle que la construction de la marge de l’Algarve s’effectue sous l’action indépendante ou conjointe des processus gravitaires et des processus contouritiques. La sédimentation de cette marge est essentiellement contrôlée par les fluctuations climato-eustatiques : (1) en haut niveau marin relatif, les processus contouritiques dominent et les drifts croissent sous l’action d’une MUW intense; (2) en bas niveau marin relatif, la MUW est affaiblit et la croissance des drifts est réduite ; les processus gravitaires deviennent dominants et permettent la mise en place de lobes perchés sur la pente. / The Algarve Margin is a contourite system principally built under the action of the Mediterranean Outflow Water (MOW). The margin evolution is strongly influenced by gravity processes as attested by the presence of numerous canyons and channel that incise continental slope. Based on analysis and interpretation of high resolution acoustic data, this thesis proposes a reconstruction of sedimentary history of Algarve Margin during Quaternary. This work improves the understanding of the interactions existing between gravity processes and contourite processes, and their forcing parameters. The present circulation pattern reflects the sedimentary facies distribution and the drift geometry. The seafloor morphology and notably presence of canyons play an important role on the orientation and intensity of the MOW upper branch (MUW). Spatial variations of oceanic circulation, such as induced by current capture by a canyon, generate differences in geometry and morphology in sedimentary deposits. Furthermore, the presence of paleochannels under the drifts underlines the existence of ancient gravity system buried by contourite construction. The filling geometry of paleochannels shows that their temporal evolution is strongly linked to the interaction between gravity currents and regional hydrodynamics. Seismic data analyse emphasizes the presence of sandy lenticular sedimentary bodies intercalated in drifts. They are interpreted as “perched lobes”. Their sand content and their rapid fossilization and preservation by drift construction, confer them an important industrial interest. During the two last million years, sedimentary deposits show that Algarve Margin developed under the action of contourite processes, gravity processes and their interactions. On this margin, the sedimentation is principally controlled by climato-eustatic variations: (1) during high sea level, contourite processes are dominant and drifts grow under the influence of intense MUW; (2) during sea level lowstand MUW decrease and drifts growth decreases; gravity processes become dominant and generate the formation of perched lobes on the slope.

Page generated in 0.3076 seconds