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    Anatomy of a mixed marine/non-marine lowstand wedge in a ramp setting. The record of a Barremian/Aptian complex relative sea-level fall in Central Neuquén Basin, Argentina

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    During the Cretaceous, western Argentina was occupied by the Neuque´n Basin, a back-arc–foreland basin that was open through the proto-Andes to the Pacific Ocean in the west. The Neuque´n Basin contains a thick succession of sediments that include the offshore marine deposits of the Agrio Formation. These deposits represent a time when the arc was an island chain and the Neuque´n Basin was freely connected to the Pacific. This offshore marine succession is punctuated by two intervals of arid continental deposits that represent major, second-order, relative falls in sea level. In both of these cases there is no evidence of tectonic uplift or angular truncation along a basal bounding unconformity. The upper of the two lowstand wedges is characterized by a complex arragement of shallow-marine and continental deposits. Shallow-marine deposits sharply overlying offshore shales and capped by a master sequence boundary are interpreted as falling-stage deposits recording a complex relative sea-level fall. On top of a regional erosion surface, a drying-upwards succession of fluvial–aeolian deposits is developed, recording a fully non-marine stage in the evolution of the basin. These deposits are overlain by a marginal marine evaporite succession. The absence of a return to fully open-marine conditions is attributed to uplift in the Andes and marks the transition of the Neuque´n Basin from a back-arc to a foreland system. This succession has important implications for the basin’s evolution and in the timing of the uplift of the Andes, is a very spectacular example of a lowstand wedge and is also a major hydrocarbon reservoir.Fil: Veiga, Gonzalo Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Howell, John. University of Bergen; NoruegaFil: Strömbäck, Anna. University of Liverpool; Reino Unid

    The transgression of an erg - sedimentation and reworking/soft-sediment deformation of aeolian facies: the Cretaceous Troncoso Member, Neuquén Basin, Argentina

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    The Cretaceous Troncoso Inferior Member of the Huitrín Formation comprises fluvial and aeolian facies that form a drying-upwards succession within the Neuquén Basin. The basal fluvial sandstones were deposited as braided river deposits and lie unconformably on top of either the deep-marine Agrio Formation or, locally, the shallow-marine Chorreado Member (Huitrín Formation.). In places, the fluvial sandstones are interbedded with remnants of aeolian deposits recording an arid environment and ephemeral flows. In the study area the upper section is predominantly aeolian and was controlled by northerly winds with both linear and transverse dune types being deposited. The depositional system was rapidly flooded and dune topography (relief ranging between 2 and 35 m) was preserved on its top surface. In addition to dune topography, the Troncoso dunes also show evidence of reworking and in situ soft-sediment deformation related to the flooding. The principal aim of this paper is to document the soft-sediment deformation and preservation of topography associated with the flooding of the dune field. Within the soft sediment deformed and reworked sediments at the top of the Troncoso Inferior Member spatial and temporal relationships indicate that they formed in a specific sequence. Initially, water-escape processes created convolutedly folded and dish structures that were concentrated in areas of slightly higher preserved dune topography. Secondly, the convolutedly folded and dish facies were eroded and reworked by wave undercutting and migrating three-dimensional dunes in a shallow-marine environment. This subaqueous reworking resulted in an interbedded massive and cross-stratified unit. With further deepening of the water, the topography became stabilized and the uppermost part of the interval (0.1–0.3 m) was reworked by waves across most of the basin. In the topographic lows between dunes, liquefaction-induced sediment gravity flows deposited massive-flatlaminated facies. The reworked and soft-sediment deformed aeolian dune topography is overlain by the evaporites of the Troncoso Superior Member. The distribution of flood-related facies and the amount of preserved dune topography (2–35 m) indicates that the transgression must have been rapid but of low energy.Fil: Strömback, Anna. University of Liverpool; Reino UnidoFil: Howell, John. University of Bergen; NoruegaFil: Veiga, Gonzalo Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentin

    The Neuquén Basin: An overview

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    The Neuquén Basin of Argentina and central Chile contains a near-continuous Late Triassic-Early Cenozoic succession deposited on the eastern side of the evolving Andean mountain chain. It is a polyphase basin characterized by three main stages of evolution: initial rift stage; subduction-related thermal sag; and foreland stage. The fill of the basin records the tectonic evolution of the central Andes with dramatic evidence for base-level changes that occurred both within the basin and along its margins. The record of these changes within the mixed siliclastic-carbonate succession makes the basin an excellent field laboratory for sequence stratigraphy and basin evolution. The 4000 m-thick fill of the basin also contains one of the most complete Jurassic-Early Cretaceous marine fossil records, with spectacular finds of both marine and continental vertebrates. The basin is also the most important hydrocarbon-producing province in southern South America, with 280.4 × 106 m3 of oil produced and an estimated 161.9 × 106 m3 remaining. The principal components of the hydrocarbon system (source and reservoir) crop out at the surface close to the fields. The deposits of the basin also serve as excellent analogues to reservoir intervals worldwide.Fil: Howell, John. University of Bergen; NoruegaFil: Schwarz, Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Spalletti, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Veiga, Gonzalo Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentin

    Nelson Lichtenstein & Howell John Harris, eds. — Industrial Democracy in America, The Ambiguous Promise

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    Collomp Catherine. Nelson Lichtenstein & Howell John Harris, eds. — Industrial Democracy in America, The Ambiguous Promise. In: Revue Française d'Etudes Américaines, N°59, février 1994. La présence américaine en France XIXe-XXe siècles. p. 102

    Howell John HARRIS. Bloodless Victories : The Rise and Fall of the Open Shop in the Philadelphia Metal Trades, 1890-1940.

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    Howell John Harris’s magisterial history of labor relations in the Philadelphia metal trades has provoked surprisingly little discussion thus far in the United States. Three years after its publication, the book had garnered only a smattering of reviews by labor historians. Indeed, the U.S. journal of record, Labor History, had yet to review the book. Nor had this long-awaited volume by a well-known and passionate participant in U.S. labor historians’ debates drawn the attention of scholarly ..

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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