1,720,973 research outputs found

    Medieval relative low sea-level indications from the Peloponnese and the Aegean Sea

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    This research is an interdisciplinary study of changes in relative sea level (RSL) in the Peloponnese and the Aegean Sea during the last 1000 years that links archaeological sea-level indicators, from medieval constructions and historical accounts with geological processes. Site survey was conducted in the south Peloponnese, Crete and Paros Island. The study evaluates the 'functional height' of the archaeological remains and dates them based on archaeological and historical records. The archaeological indicators were compared to other indications made by previous studies and to the predicted RSL. The results correlate with the RSL indications in previous studies, but they are below the predicted curve. The difference can be attributed to both the Glacial Isostatic Adjustment (GIA) and to tectonic contributions, which are in agreement with other studies in the area. The current study calculates a low RSL of about −1.3m in the south Peloponnese of the 5th century CE, rising gradually to about −0.5 m at the 15th century. In the Cyclades Plateau RSL of −1.2m is estimated for the end of 13th century, climbing to −0.7m by the beginning of the 16th century. The archaeological sea-level indicators in the south Peloponnese and the Aegean Sea confirm the low medieval sea levels found in other Mediterranean sites

    Paleo-Urban Development and Late Quaternary Environmental Change in the Akko Area

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    Holocene sea level changes as well as regional and local tectonic movements determined the configuration of the Mediterranean coast of northern Israel. This, in turn, influenced the location and type of settlements, in particular of Akko. The paleoenvironment and paleogeography of Akko bay are tentatively reconstructed here through the study of the stratigraphy and nature of the deposits.Des changements de niveau à l'holocène aussi bien que des mouvements régionaux et locaux déterminèrent la configuration de la côte nord d'Israël. Ces modifications influencèrent à leur tour l'emplacement et le type des établissements, en particulier d'Akko. Un essai de reconstruction du paléoenvironnement et de la paléogéographie est tenté ici à travers l'étude de la stratigraphie et de la nature des dépôts.Inbar Moshe, Sivan Dorit. Paleo-Urban Development and Late Quaternary Environmental Change in the Akko Area. In: Paléorient, 1983, vol. 9, n°2. pp. 85-91

    Late-Pleistocene evolution of the continental shelf of central Israel, a case study from Hadera

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    Sea-level fluctuations are a dominant mechanism that control coastal environmental changes through time. This is especially the case for the successive regressions and transgressions over the last interglacial cycle, which have shaped the deposition, preservation and erosion patterns of unconsolidated sediments currently submerged on continental shelves. The current study focuses on creating an integrated marine and terrestrial geophysical and litho-stratigraphic framework of the coastal zone of Hadera, north-central Israel. This research presents a case study, investigating the changing sedimentological units in the study area. Analysis suggest these represent various coastal environments and were deposited during times of lower than present sea level and during the later stages of the Holocene transgression.A multi-disciplinary approach was applied by compiling existing elevation raster grids, bathymetric charts, one hundred lithological borehole data-sets, and a 110 km-long sub-bottom geophysical survey. Based on seismic stratigraphic analysis, observed geometries, and reflective appearances, six bounding surfaces and seven seismic units were identified and characterized. These seismic units have been correlated with the available borehole data to produce a chronologically constrained lithostratigraphy for the area. This approach allowed us to propose a relationship between the lithological units and sea-level change and thus enable the reconstruction of Hadera coastal evolution over the last ~ 100 ka. This reconstruction suggests that the stratigraphy is dominated by lowstand aeolian and fluvial terrestrial environments, subsequently transgressed during the Holocene. The results of this study provide a valuable framework for future national strategic shallow-water infrastructure construction and also for the possible locations of past human settlements in relation to coastal evolution through time

    New perspectives on coastal landscape reconstruction during the Late Quaternary: a test case from central Israel

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    The stratigraphic architecture of coastal plains is determined by the interactions between local (e.g. fluvial processes and topography), regional (e.g. climate) and global (e.g. sea level) forcing factors, primarily during the Late Quaternary Period. Detailed stratigraphic and sedimentological analyses of boreholes, cored between coastal ridges in the lowlands, coupled with optically stimulated luminescence (OSL) dating, and integrated with existing onshore and offshore databases, has enabled a 4-D reconstruction of the evolution of the coast of Israel during the last glacial-interglacial cycle. This model revealed that Nilotic-sourced littoral sand, intermittently transported inland by wind, has either been lithified into aeolianite or pedogenized into orange–brown palaeosol from about 100 ka to 8 ka. Dark silty clay wetlands were deposited between the aeolian coastal ridges adjacent to streams which cut the Israeli coastal plain and flow westward, from the Last Glacial Maximum until the onset of the Holocene. These units are topped by beach and aeolian quartz sand dated to 6.6–0.1 ka. Diachronous thicknesses and lithological dissimilarities were identified between the sections studied and previous reports on adjacent coastal aeolianite ridges. Streams were found to be a dominant control on the stratigraphical composition and related facies architecture due to fluvial-induced erosion. Consequently, the relief variations between the lowland and cliff controlled aeolian pedogenesis as well as alluvial processes from about 80 to 5 ka. Climate, mainly influenced by precipitation and dust input, induced pedogenic processes; while sea level lowstand during the Last Glacial Maximum is shown to have hindered sediment deposition in the shallow offshore, which in turn affected aeolian transport, reducing sediment accumulation on the palaeo-coastal plain. The palaeoenvironmental model presented in the current study serves as an example for understanding the evolution of similar low-latitude siliciclastic-rich low-gradient shelf-coastal areas during the last glacial-interglacial cycle. Furthermore, it demonstrates the influence of local to global forcing factors on these environments

    Can we detect centennial sea-level variations over the last three thousand years in Israeli archaeological records?

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    Archaeological remains are valuable relative sea-level (RSL) indicators in Israel, a tectonically stable coast with minor isostatic inputs. Previous research has used archaeological indicators to argue for centennial sea-level fluctuations. Here, we place archaeological indicators in a quality-controlled dataset where all indicators have consistently calculated vertical and chronological uncertainties, and we subject the data to statistical analysis. We combine the archaeological data with bio-construction data from Dendropoma petraeum colonial vermetids. The final dataset consists of 99 relative sea-level index points and 12 limiting points from the last 4000 a. The temporal distribution of the index points is uneven; Israel has only four index points before 2000 a BP. We apply an Errors-In-Variables Integrated Gaussian Process (EIV IGP) to the index points to model the evolution of RSL. Results show RSL in Israel rose from −0.8 ± 0.5 m at ∼2750 a BP (Iron Age) to 0.0 ± 0.1 m by ∼1850 a BP (Roman period) at 0.8 mm/a, and continued rising to 0.1 ± 0.1 m until ∼1600 a BP (Byzantine Period). RSL then fell to −0.3 ± 0.1 m by 0.5 mm/a until ∼650 a BP (Late Arab period), before returning to present levels at a rate of 0.4 mm/a. The re-assessed Israeli record supports centennial-scale RSL fluctuations during the last 3000 a BP, although the magnitude of the RSL fall during the last 2000 a BP is 50% less. The new Israel RSL record demonstrates correspondence with regional climate proxies. This quality-controlled Israeli RSL dataset can serve as a reference for comparisons with other sea-level records from the Eastern Mediterranean

    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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