53 research outputs found

    Quaternary Sedimentation in the St. Lawrence Estuary and Adjoining Areas, Eastern Canada: An Overview Based on High-Resolution Seismo-Stratigraphy

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    The regional Quaternary seismo-stratigraphy of NW Gulf of St. Lawrence, based on 5700 line km of high resolution seismic reflection profiles, is described. The Quaternary sequence can be locally missing or can exceed 1.3 km in thickness. Five major stratigraphic units are recognized, which vary in their character and distribution so that at any location a variety of bedrock types may be overlain by a distinctive Quaternary sequence. These units relate to the advance and retreat of the Late Wisconsinan Ice Sheet. We interpret these units as: Unit 1, recording the presence of grounded glacial ice, including ice-loaded and ice-deposited sediments. Unit 2, ice-proximal coarse-grained sediment deposited either as a thin, conformable layer during the rapid retreat of an ice terminus, or as a wedge-shaped fan marking the position of an ice front still stand. Unit 3, ice-distal fine-grained sediment deposited from meltwater plumes at times of elevated sea levels and rapidly ablating sea ice. Unit 4, paraglacial deltaic sediment marking the melting of terrestrially-based ice caps, and the concommittant growth of deltas, rapidly prograding into a seaway undergoing rapidly falling sea levels. Unit 5, postglacial sediment reflecting the winnowing of shallow areas and deposition of organic-rich mud in deep basins, under modern sea level and océanographie conditions. A conceptual model dealing with the deposition of sediment associated with the withdrawal of a continental ice sheet is developed. The model includes the dynamics associated with the initial ice advance, terminal ice dynamics, retreat of the ice terminus, stable ice-fronts during the recessional phase, ice sheets ablating on land, and postglacial sedimentation under conditions of fluctuating sea levels.Le présent article se fonde sur des profils effectués par sismique reflection sur 5700 kilomètres dans le nord-ouest du golfe du Saint-Laurent. La séquence quaternaire, parfois absente, peut ailleurs avoir plus de 1,3 kilomètre d'épaisseur. On a relevé cinq grandes unités stratigraphiques dont la nature et la répartition varient. Liées à l'évolution de l'inlandsis du Wisconsinien supérieur, elles se présentent comme suit: unité 1 : sédiments de contact renfermant des sédiments comprimés par le glacier et d'autres déposés par lui; unité 2: sédiments proximaux grossiers, déposés soit en une couche mince et concordante durant le retrait rapide d'un front, soit sous forme de cône marquant la position d'un front stable; unité 3: sédiments distaux fins, déposés par des langues d'eau de fusion dans une mer à niveaux élevés et dont la glace fondait rapidement; unité 4: sédiments deltaïques paraglaciaires révélant la fusion de glaces continentales et la formation rapide et concomitante de deltas dans une mer accusant de fortes baisses de niveau : unité 5: sédiments postglaciaires révélant le triage de zones peu profondes et le dépôt, en profondeur, de boues riches en matières organiques, dans des conditions rappelant celles d'aujourd'hui. Un modèle, exposant les étapes de sédimentation associées au retrait d'un inlandsis, tient compte des dynamiques associées à la première avancée glaciaire, à la position glaciaire finale, au retrait du front glaciaire, à la stabilité du front pendant le retrait, à la fusion de l'inlandsis et à la sédimentation postglaciaire dans une mer aux niveaux changeants.Die régionale Quaternâr Seismo-Stratigraphie des Nordwestens vom Sankt-Lorenz-Golf wird beschrieben, gestûtzt auf 5700 km lange seismische Reflexions-profile mit hoher Auflôsung. Die Quatemàr-Sequenz kann stellenweise fehlen oder auch ùber 1.3 km dick sein. Fùnf stratigraphische Haupt einheiten werden bestimmt. Einheit 1, welche das Vorhandensein von glazialem bodeneis einschliesslich durch Eis kompri-mierte und durch Eis abgelagerte Sedimente dokumentiert. Einheit 2, ein grobgekôrntes Eisproximal-Sediment, das entweder als eine dùnne, gleichgelagerte Schicht wâhrend des schnellen Rûckzugs eines Eisterminus abgelagert wurde, oder als ein keilfôrmiger Fâcher, der den Stillstand einer Eisfront markiert. Einheit 3, ein feinkôrniges Eis-Distal-Sediment, das von Schmelzwasserzungen in Zeiten erhôhter Meeresspiegel und rasch schmelzenden Meereises abgelagert wurde. Einheit 4. ein paraglaziales Delta-Sediment, welches das Schmelzen von auf dem Festland gelagerten Eiskappen markiert und das damit verbundene Anwachsen der Deltas, die schnell zu einem Seeweg vorrùckten und schnell fallenden Meeresspiegeln ausgesetzt waren. Einheit 5, ein postglaziales Sediment, das das Aussortieren seichter Gebiete spiegelt sowie Ablagerung von organisch reichem Schlamm in tiefen Becken und das unter modernen Meeresspiegel - und ozeanographischen Bedingungen. Es wird ein Begriffsmodell entwickelt, das sich mit der Ablagerung von Sediment im Zusammenhang mit dem Ruckzug einer kontinentalen Eisdecke befasst

    Louise Müller e o Jogo da Filosofia Africana: Lopes, Marcos Carvalho. Louise Müller e.o. Jogo Da Filosofia Africana." In Tcholonadur: Entrevistas Sobre Filosofia Africana, edited by Marcos Carvalho Lopes, 183-95. São Carlos: Pedro & João Editores, 2023.

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    Louise Müller e o jogo da filosofia africana*“O conhecimento é como um baobá, nenhuma pessoa sozinha pode abraçá-lo”. Esse é um provérbio Akan que pode ser combinado com outro que diz “Que nenhuma cidade (polis) possui sozinha a verdade”. Nenhuma cidade poderia almejar a posse integral da verdade. É nesse sentido que a filósofa holandesaLouise Müller, especialista na cultura akan, tem se dedicado à filosofia africana, desenvolvendo diálogos interculturais, assim como, buscando se aprofundar nos conhecimentos de línguas e culturas africanas.Modern and Contemporary Studie

    Emerging IT risks: insights from German banking

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    How do German banks manage the emerging risks stemming from IT innovations such as cyber risk? With a focus on process, roles and responsibilities, field data from ten banks participating in the 2014 ECB stress test were collected by interviewing IT managers, risk managers and external experts. Current procedures for handling emerging risks in German banks were identified from the interviews and analysed, guided by the extant literature. A clear gap was found between enterprise risk management (ERM) as a general approach to risks threatening firms’ objectives and ERM’s neglect of emerging risks, such as those associated with IT innovations. The findings suggest that ERM should be extended towards the collection and sharing of knowledge to allow for an initial understanding and description of emerging risks, as opposed to the traditional ERM approach involving estimates of impact and probability. For example, as cyber risks emerge from an IT innovation, the focus may need to switch towards reducing uncertainty through knowledge acquisition. Since individual managers seldom possess all relevant knowledge of an IT innovation, various stakeholders may need to be involved to exploit their expertise

    When workplace unionism in global value chains does not function well : exploring the impediments

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    Improving working conditions at the bottom of global value chains has become a central issue in our global economy. In this battle, trade unionism has been presented as a way for workers to make their voices heard. Therefore, it is strongly promoted by most social standards. However, establishing a well-functioning trade union is not as obvious as it may seem. Using a comparative case study approach, we examine impediments to farm-level unionism in the cut flower industry in Ethiopia. For this purpose, we propose an integrated framework combining two lenses, namely a vertical one (governance and structure of global value chains) and a horizontal one (socio-economic context). We identify 10 impediments that point to three major dimensions contributing to unionisation. These three dimensions include awareness of and interest from workers, legitimacy of trade unions, and capacity of trade unions to act. Furthermore, our results suggest that private social standards may, in certain cases, be counterproductive for the efficient functioning of trade unions. Although we argue that there is no ‘quick fix’ solution to weak workplace unionism at the bottom of global value chains, we stress the importance of considering the dynamics of, and interactions between, the impediments when designing potential support measures that mitigate negative impacts

    Work-to-family enrichment and gender inequalities in eight European countries

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    All social roles have positive and rewarding as well as negative/problematic aspects. Research on the work–family interface has predominantly focused on conflicting roles. In contrast, this paper extends research on work–family enrichment (WFE), a positive aspect of work and gender differences in WFE in a cross-national context. Drawing upon social role theory and the culture sensitive theory on work–family enrichment, we examined gender differences in experiences of developmental WFE in a sample of service sector employees in eight European countries. In line with traditional gender roles, women reported more WFE than men. The relationship was moderated by both an objective and subjective measure of gender egalitarianism but in the opposite direction as hypothesized. The gender gap in WFE was larger in more gender-egalitarian countries, where women may be better able to transfer resources from the work domain to benefit their family role than in low egalitarian societies. National differences in labour market factors, family models and the public discourse on work–life balance mainly explain the unanticipated findings

    Part-time work and gender inequality in Europe: a comparative analysis of satisfaction with work–life balance

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    Part-time work is an increasingly common strategy for handling work and family – but is it an effective strategy everywhere and for everyone? To answer this question, we examine satisfaction with work–life balance (SWLB) of workers in 22 European countries. Our results show that part-time workers have higher SWLB than full-time workers; the more so, the fewer hours they put in. Yet, we find an important gender difference: women in marginal part-time work are more satisfied than men in a similar situation, and conversely men in full-time work have higher SWLB than women working full-time. Further, the societal context plays an important role: substantial part-time work is more conducive to SWLB in more gender-egalitarian countries than in countries with low gender equality. Hence, a supportive gender climate and institutional support may entice workers to reduce working hours moderately, which results in markedly increased levels of SWLB

    Part-time work and gender inequality in Europe: a comparative analysis of satisfaction with work–life balance

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    Part-time work is an increasingly common strategy for handling work and family – but is it an effective strategy everywhere and for everyone? To answer this question, we examine satisfaction with work–life balance (SWLB) of workers in 22 European countries. Our results show that part-time workers have higher SWLB than full-time workers; the more so, the fewer hours they put in. Yet, we find an important gender difference: women in marginal part-time work are more satisfied than men in a similar situation, and conversely men in full-time work have higher SWLB than women working full-time. Further, the societal context plays an important role: substantial part-time work is more conducive to SWLB in more gender-egalitarian countries than in countries with low gender equality. Hence, a supportive gender climate and institutional support may entice workers to reduce working hours moderately, which results in markedly increased levels of SWLB

    Methane Seepage on Mars: Looking for analogues from submarine fluid flow systems on Earth

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    Methane Seepage on Mars: Looking for analogues from submarine fluid flow systems on Eart

    Episodic Cenozoic tectonism and the development of the NW European 'passive' continental margin

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    The North Atlantic margins are archetypally passive, yet they have experienced post-rift vertical movements of up to kilometre scale. The Cenozoic history of such movements along the NW European margin, from Ireland to mid-Norway, is examined by integrating published analyses of uplift and subsidence with higher resolution tectono-stratigraphic indicators of relative movements (including results from the STRATAGEM project). Three episodes of epeirogenic movement are identified, in the early, mid- and late Cenozoic, distinct from at least one phase of compressive tectonism. Two forms of epeirogenic movement are recognised, referred to as tilting (coeval subsidence and uplift, rotations <1° over distances of 100s of Kilometres) and sagging (strongly differential subsidence, rotations up to 4° over distances <100 km). Each epeirogenic episode involved relatively rapid (<10 Ma) km-scale tectonic movements that drove major changes in patterns of sedimentation to find expression in regional unconformity-bounded stratigraphic units. Early Cenozoic tilting (late Paleocene to early Eocene, c. 60–50 Ma) caused the basinward progradation of shelf-slope wedges from elongate uplifts along the inner continental margin and from offshore highs. Mid-Cenozoic sagging (late Eocene to early Oligocene, c. 35–25 Ma) ended wedge progradation and caused the onset of contourite deposition in deep-water basins. Late Cenozoic tilting (early Pliocene to present, <4±0.5 Ma) again caused the basinward progradation of shelf-slope wedges, from uplifts along the inner margin (including broad dome-like features) and from offshore highs. The early, mid- and late Cenozoic epeirogenic episodes coincided with Atlantic plate reorganisations, but the observed km-scale tectonic movements are too large to be accounted for as flexural deflections due to intra-plate stress variations. Mantle–lithosphere interactions are implied, but the succession of epeirogenic episodes, of differing form, are difficult to reconcile with the various syn-to post-rift mechanisms of permanent and/or transient movements proposed in the hypothetical context of a plume beneath Iceland. The epeirogenic movements can be explained as dynamic topographic responses to changing forms of small-scale convective flow in the upper mantle: tilting as coeval upwelling and downwelling above an edge-driven convection cell, sagging as a loss of dynamic support above a former upwelling. The inferred Cenozoic succession of epeirogenic tilting, sagging and tilting is proposed to record the episodic evolution of upper mantle convection during ocean opening, a process that may also be the underlying cause of plate reorganisations. The postulated episodes of flow reorganisation in the NE Atlantic region have testable implications for epeirogenic movements along the adjacent oceanic spreading ridge and conjugate continental margin, as well as on other Atlantic-type ‘passive’ margin
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