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Climate and sea level variations in the Gulf of Lion : coupling stable and radiogenic isotopes proxies / Variations climatiques et glacio-eustatiques dans le Golfe du Lion : une approche couplée des isotopes stables et radiogéniquesPasquier, Virgil 17 November 2017 (has links)
De par sa position, le Golfe du Lion est un site idéal pour l’investigation des changements paléo-environnementaux et des processus affectant le dépôt sédimentaire. Les travaux antérieurs ont permis de mettre en évidence les impacts de la variabilité climatique et glacioeustatique sur l’organisation stratigraphique de la marge, mais également sur les exports terrestres de matière organique.L’étude isotopique du carbone organique et de l’azote de la matière organique dans les sédiments du forage PRGL1-4 nous a permis de mettre en évidence de forts exports fluviaux lors des interstades survenus au cours des 200 000 derniers milles ans. La mise en regard de cette découverte avec les enregistrements paléo-climatologiques terrestre et marin disponibles dans la région indique que ces forts exports fluviaux résultent d’une augmentation des précipitations le long de la bordure Nord Méditerranéenne. Grâce à la position dePRGL1-4, nous proposons que ces pluies soient le résultat d’une augmentation du passage de dépressions Nord Atlantique dans le bassin Ouest Méditerranéen.Une caractérisation des isotopes du soufre préservés dans la pyrite sédimentaire a été réalisée. Les résultats obtenus ont permis de mettre en évidence une variation isotopique insoupçonnée, l’une des plus grandes observées de nos jours, dont la cyclicité semble indiquer un fort contrôle climatique. Nous proposons deux mécanismes influençant le fractionnement isotopique: une modulation de l’activité bactérienne par le climat, et/ou (ii) une modulation locale liée la nature des sédiments impliqués dans la formation des pyrites en lien avec les variations eustatiques. / By its position, the Gulf of Lion is an ideal location for investigation of past ecological changes and processes affecting the sedimentary deposition. Previous work has highlighted the impacts of climatic and glacio-eustatic changes on the GoL stratigraphic organization, but also on terrestrial exports of organic matter.This isotopic study based on the organic carbon and nitrogen preserved in PRGL1-4 sediments highlights important rivers runoff during warm periods of the last 200 000 years.Regional intercomparison with terrestrial and marine records indicates that these river exports resulting from an increase of precipitation over the North Mediterranean borderland.Using PRGL1-4 location, out of Mediterranean cyclogenetic area, we suggest that these pluvial events occurred in response to enhance passage of North Atlantic atmospheric perturbation into the Western Mediterranean basin.Pyrite sulfur isotopes investigations over the last 500 kyr have also been done. The stratigraphic variations (up to 76‰) in the isotopic data reported here are among the largest ever observed in pyrite, and are in phase with glacial-interglacial sea level. These results suggest that there exist important but previously overlooked depositional controls on sedimentary sulfur isotope records. Two different mechanisms influencing the isotopic fractionation can explain the observed dataset: a climatic modulation of the bacterial activity, and / or (ii) a local sedimentary modulation involve during early diagenetic formation of pyrite in relation with the eustatic variations.
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Teachers’ mo(u)rning stories: A living narrative inquiry into teachers’ identities on emergent high school inquiry landscapes2013 August 1900 (has links)
This particular telling and retelling from a living narrative inquiry (Clandinin & Connelly, 2000) into the early experiences of three high school science teachers – Beth, Joel, and Christina – explores the emergent inquiry landscapes constructed as we implemented a renewed, decolonizing, science curriculum in Saskatchewan founded on a philosophy of inquiry and on a broader, more holistic definition of scientific literacy, both Western and Indigenous. This inquiry draws on an ontology of lived experience (Dewey, 1938) and, more subtly, on the borderland of narrative inquiry and complexity science in order to illustrate the emergence and coming to knowing (Delandshire, 2002; Ermine, as cited in Aikenhead, 2002) of our identities in a way that avoids the reduction in complexity of our experiences. While my initial wonders persisted throughout the research as I lived alongside Beth, Joel, and Christina for two years, they diffracted into the contextualized wonder: how do we share a philosophy of inquiry with each other and with our students? As such, this inquiry is a sharing about our own identities, about our own agency, about identity work, and about which experiences we choose to (re)engage with as we attempt to (re)find the narrative diversity, both individual and collective, necessary to shift from enacted identities to 'wished-we-could-enact' identities. This exploration of our 'mo(u)rning stories', early experiences from our shifting identities after stepping through the liminal and onto emergent inquiry landscapes, or our 'stories to relive with' provides a language and context to our shifting identities and hence, to science education, as we move towards a more holistic and humanistic form of scientific literacy for all our students. What emerged through the enmeshing of our landscapes and through the construction of voids in existing practices, followed by deformalizations in assessment and planning, was the development of a way of sharing our philosophy of inquiry and hence, our shifting identities. The artifacting and sharing of our contextualized inquiry experiences highlighted the rich assessment making, and curriculum making experiences (Huber, Murphy & Clandinin, 2011) we shared with our students and highlighted a view of assessment as a relationship. As we told and retold our stories to relive with, our identities shifted towards those more akin to facilitator and anthropologist and away from sage and engineer/architect.
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Ethnonyms in the place-names of Scotland and the Border counties of EnglandMorgan, Ailig Peadar Morgan January 2013 (has links)
This study has collected and analysed a database of place-names containing potential ethnonymic elements. Competing models of ethnicity are investigated and applied to names about which there is reasonable confidence. A number of motivations for employment of ethnonyms in place-names emerge. Ongoing interaction between ethnicities is marked by reference to domain or borderland, and occasional interaction by reference to resource or transit. More superficial interaction is expressed in names of commemorative, antiquarian or figurative motivation. The implications of the names for our understanding of the history of individual ethnicities are considered. Distribution of Walh-names has been extended north into Scotland; but reference may be to Romance-speaking feudal incomers, not the British. Briton-names are confirmed in Cumberland and are found on and beyond the fringes of the polity of Strathclyde. Dumbarton, however, is an antiquarian coining. Distribution of Cumbrian-names suggests that the south side of the Solway Firth was not securely under Cumbrian influence; but also that the ethnicity, expanding in the tenth century, was found from the Ayrshire coast to East Lothian, with the Saxon culture under pressure in the Southern Uplands. An ethnonym borrowed from British in the name Cumberland and the Lothian outlier of Cummercolstoun had either entered northern English dialect or was being employed by the Cumbrians themselves to coin these names in Old English. If the latter, such self-referential pronouncement in a language contact situation was from a position of status, in contrast to the ethnicism of the Gaels. Growing Gaelic self-awareness is manifested in early-modern domain demarcation and self-referential naming of routes across the cultural boundary. But by the nineteenth century cultural change came from within, with the impact felt most acutely in west-mainland and Hebridean Argyll, according to the toponymic evidence. Earlier interfaces between Gaelic and Scots are indicated on the east of the Firth of Clyde by the early fourteenth century, under the Sidlaws and in Buchan by the fifteenth, in Caithness and in Perthshire by the sixteenth. Earlier, Norse-speakers may have referred to Gaels in the hills of Kintyre. The border between Scotland and England was toponymically marked, but not until the modern era. In Carrick, Argyll and north and west of the Great Glen, Albanians were to be contrasted, not necessarily linguistically, from neighbouring Gaelic-speakers; Alba is probably to be equated with the ancient territory of Scotia. Early Scot-names, recorded from the twelfth century, similarly reflect expanding Scotian influence in Cumberland and Lothian. However, late instances refer to Gaelic-speakers. Most Eireannach-names refer to wedder goats rather than the ethnonym, but residual Gaelic-speakers in east Dumfriesshire are indicated by Erisch-names at the end of the fifteenth century or later. Others west into Galloway suggest an earlier Irish immigration, probably as a consequence of normanisation and of engagement in Irish Sea politics. Other immigrants include French estate administrators, Flemish wool producers and English feudal subjects. The latter have long been discussed, but the relationship of the north-eastern Ingliston-names to mottes is rejected, and that of the south-western Ingleston-names is rather to former motte-hills with degraded fortifications. Most Dane-names are also antiquarian, attracted less by folk memory than by modern folklore. The Goill could also be summoned out of the past to explain defensive remains in particular. Antiquarianism in the eighteenth century onwards similarly ascribed many remains to the Picts and the Cruithnians, though in Shetland a long-standing supernatural association with the Picts may have been maintained. Ethnicities were invoked to personify past cultures, but ethnonyms also commemorate actual events, typified by Sasannach-names. These tend to recall dramatic, generally fatal, incidents, usually involving soldiers or sailors. Any figures of secular authority or hostile activity from outwith the community came to be considered Goill, but also agents of ecclesiastical authority or economic activity and passing travellers by land or sea. The label Goill, ostensibly providing 178 of the 652 probable ethnonymic database entries, is in most names no indication of ethnicity, culture or language. It had a medieval geographical reference, however, to Hebrideans, and did develop renewed, early-modern specificity in response to a vague concept of Scottish society outwith the Gaelic cultural domain. The study concludes by considering the forms of interaction between ethnicities and looking at the names as a set. It proposes classification of those recalled in the names as overlord, interloper or native.
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