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The Pacific entrance of the Magellan Strait: Preliminary Result of a seismic and sampling survey
No full textDuring Spring 1995, in the frame of the Italian Programma Nazionale di Ricerche in Antartide (PNRA) 290 km of intermediate-resolution multichannel reflection profiles have been acquired in the Pacific entrance of the Magellan Strait with the RN OGS Explora.
The survey was carried out with two principal aims: a) to verify the occurrence and effects of the Magellan Fault along the western part of the South America-Scotia plate boundary, and b) to investigate the sedimentary architecture of the sequences of this sector of the Strait, with particular interest to those concerning the Pleistocene glacial events.
The survey herein described has been carried out in a marine enlargement of the Strait north of Isla Desolaciòn, between Cabo Pilar and Isla Tamar. Seismicenergy was provided by two G.I. Guns of 210 cubic inches each, with shot interval of 25m. The cable was a 48 channels -600 m streamer which furnished a 1200% coverage.
Record length was kept at 8 seconds and sampling interval at 1 ms. Three gravity cores were also collected from the bottom sediments. These data are integrated b a high-resolution seismic line longitudinal to the Strait recorded in 1991 and other three cores collected during different surveys in 1991 and 1995.
This work describes the preliminary results of the survey in terms of both tectonic and palaeoenvironmental frame. Its original aspect consists in documenting for the first time the location and characterization of the Magellan Fault along the westernmost arm of the Strait.
This result fills the gap with the central-eastern tract of the fault for which a number of works have been issued in the last years. Another aspect concerns the sedimentological data from core analyses that constrain the environmental evolution of the Pacific mouth of the Strait about the last 21 000 years
Seismostratigraphy and recent sedimentary evolution of an asymmetric extensional basin at the Western arm of the Magallanes-Fagnano transform system
No full textIn 1995, in the frame of the PNRA (Progetto Nazionale di Ricerche in Antartide) the Dipartimento di Scienze Geologiche, Ambientaie e Marine (DISGAM – University of Trieste) performed a marine geological survey within the Pacific entrance of the Magellan Strait with the aim a) to verify the occurrence and effects of the Magellan Fault along the western part of the South America-Scotia plate boundary; and b) to investigate the sedimentary architecture of the sequences of this sector of the Strait, with particular interest to those recording the Pleistocene glacial events. The survey consisted of 290km of intermediate resolution multichannel seismic reflection profiles and three gravity cores. These data were acquired in a marine enlargement of the Magellan Strait north of Isla Desolacion, between Cabo Pilar and Isla Tamar with the R/V OGS Explora (Fig. 1).
The analysed data were integrated by a high-resolution seismic line acquired all along the sStrait in 1991 and by other three cores collected during different surveys in 1991 and 1995. The present work summarize the previous report of Bartole et al. (2000) and provide new results obtained by recent analyses of the seismic and sampling data
The Pacific Entrance of the Magellan Strait: Preliminary Results of a Seismic and Sampling Survey.
No full textIndagini Side Scan Sonar nell’area delle Bocche di Bonifacio. Arcipelago di La Maddalena (Sardegna, Italia)
No full textIl settore pacifico dello Stretto di Magellano: primi risultati di un’indagine sismica a riflessione
No full text
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
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