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Petrography of the metamorphic rocks from the Agordo area bearing latest Cambrian, Aeronian and Devonian fossils (Southalpine metamorphic basement of the Eastern Alps, Italy).
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Geo-petrographic data on the metamorphic rocks with Cambrian, Silurian and Devonian fossils in the Agordo area (Southalpine metamorphic basement of the Eastern Alps, Italy).
No full textRecently, in the Agordo area, some unquestionable fossils have been described: 1) Latest Cambrian acritarchs,
within trivial black, fine grained phyllites (Col di Foglia); 2) Aeronian graptolites, within boudins along a recrystallized shear
zone cutting low-grade metapelites (Ponte Alto); 3) Middle Devonian Rugosa corals, within metalimestone boudins along
the mentioned shear zone. These fossil findings are unique in this basement, therefore, the rocks containing them deserve
a careful petrographic investigation. This paper presents the basic petrographic features of the rock samples containing
the fossils. All the rocks underwent a greenschist facies metamorphism (chlorite zone) under a thermal gradient of ca.
38°C/Km. The most interesting rocks are those bearing well preserved graptolites which mainly consist of quartz,
fluorapatite (up to 70%.), carbonaceous matter and sulphides. T in the boudins turns out to be slightly lower than in the
surrounding matrix
Epilithic organisms in Priabonian marls with pillow lavas from the EuganeanHills (NE Italy)
Full text linkIn the Castelnuovo area of the Euganean Hills, upper Priabonian marls (referred to as Brendola Marl) are associated with products of submarine basaltic eruptions, including pillow lavas and lava flows, pertaining to the first, late Eocene magmatic phase in the district. A biostratigraphical revision of the marl by means of calcareous nannofossils allowed to ascribe the succession to the Priabonian Zone CNE19 (Agnini et al., 2014) and to the upper part of planktonic foraminiferal Zone E15, with an estimated age of 35.3-34.3 Ma (Berggren and Pearson, 2005). The benthic foraminiferal assemblage provided a palaeodepth estimation suggesting a deep neritic environment. A reconstruction of the late Priabonian events in the study area indicates various episodes of submarine eruptive activity with formation of pillows and associated hyaloclastic material, alternating with phases of colonization of the upper parts of the pillows and larger hyaloclasts by epilithic and vagile organisms such as cr..
Epilithic organisms in Priabonian marls with pillow lavas of Euganean Hills (NE Italy)
No full textIn the Castelnuovo area of the Euganean Hills, upper Priabonian marls (referred to as Brendola Marl) are associated with products of submarine basaltic eruptions, including pillow lavas and lava flows, pertaining to the first, late Eocene magmatic phase in the district. A biostratigraphical revision of the marl by means of calcareous nannofossils allowed to ascribe the succession to the Priabonian Zone CNE19 (Agnini et al., 2014) and to the upper part of planktonic foraminiferal Zone E15, with an estimated age of 35.3-34.3 Ma (Berggren and Pearson, 2005). The benthic foraminiferal assemblage provided a palaeodepth estimation suggesting a deep neritic environment. A reconstruction of the late Priabonian events in the study area indicates various episodes of submarine eruptive activity with formation of pillows and associated hyaloclastic material, alternating with phases of colonization of the upper parts of the pillows and larger hyaloclasts by epilithic and vagile organisms such as crinoids, cirripeds, brachiopods and cidarid echinoids, followed by their post-mortem disaggregation, dispersal and eventual burial due to the uninterrupted marly sedimentation. These episodes ceased with the emplacement of a lava flow, whose flat top was colonized only by sparse cirripeds
Cambrian Acritarchs from the Col di Foglia (Agordo) southalpine metamorphic basement, Italian Eastern Alps: the oldest biostratigraphic record in the alps
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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