1,720,957 research outputs found
African-Eurasian Plate Boundary in the Ionian Sea: shortening and strike slip deformation in the outer Calabrian Arc accretionary wedge
No full textThe Apenninic-Maghrebian Prism of Inner Calabrian Arc as imaged by subsurface data in the Squillace embayment (Calabria, Southern Italy)
No full textL’arco Calabro è stato oggetto di molti studi che hanno messo in luce, tra l’altro, la presenza di un nappe di basamento cristallino ad affinità alpina ed il ruolo importante della tettonica estensionale nonché l’evoluzione tettonicosedimentaria
a partire dal Paleogene. Tuttavia, persistono ancora alcune questioni aperte relativamente a: 1) unità stratigrafiche e tettoniche che costituiscono l’arco Calabro interno; 2) precisa cronologia della deformazione; 3) ammontare e distribuzione spaziale della distensione. Per contribuire a rispondere a questi problemi, ai dati già noti, tra cui tre linee CROP riprocessate, abbiamo integrato i logs di pozzi e linee sismiche della zona D ed F che sono di pubblico dominio ma poco utilizzati in letteratura. L’insieme di questi diversi dati, a diverse scale di osservazione, ha permesso di individuare quattro unità tettoniche che caratterizzano la zona più interna (backstop) dell’arco Calabro interno.
L’unità tettonica più alta è costituita dai basamenti cristallini che, distesi durante l’Oligocene-Miocene inferiore, è stata successivamente traslata a ricoprire parzialmente il prisma Appenninico-Magrebide. Quest’ultimo è suddivisibile in due unità tettoniche le quali, in accordo con la loro posizione e all’età di deformazione, sono nominate: unità tettonica superiore del prisma Appenninico-Magrebide che è sigillata da depositi marini del Miocene medio e superiore; unità tettonica inferiore del prisma Appenninico-Magrebide sigillata da depositi più vecchi (Paleogene?). Al di sotto del prisma Appenninico-Magrebide, si evidenzia una quarta unità tettonica relativamente poco deformata tranne che da sistemi di faglie estensionali pressoché sigillate da depositi presumibilmente profondi e distali di età variabile dal Paleogene al
Miocene. Dal Pliocene sino all’attuale, le unità tettoniche evidenziate sono state riattivate e rimodellate contemporaneamente allo sviluppo di sistemi di strutture trascorrenti orientate ESE-WNW.
I risultati ottenuti nella zona del Golfo di Squillace, oltre a fornire una migliore comprensione dell’evoluzione dell’arco Calabro interno, dovrebbero permettere di meglio prevedere il suo futuro sviluppo in relazione ai rischi
naturali associati ad un cuneo orogenico che si sta formando
Structure and evolution of the Calabrian Arc accretionary Wedge (Ionian Sea) from deep reflection seismic data
No full textThe Apenninic-Maghrebian prism of Inner Calabrian Arc as imaged by subsurface data in the Squillace embayment (Calabria, Southern Italy).
No full textAfrican/Eurasian plate boundary in the Ionian Sea: shortening and strike slip deformation in the outer Calabrian Arc accretionary wedge.
No full textThe Calabrian Arc (CA) subduction system is part of the complex African-Eurasian plate boundary in the central Mediterranean Sea and connects the NW/SE trending Apennine with the E-W trending Magrebian thrust belt. Previous studies have outlined the overall architecture of the subduction complex in the Ionian Sea through the analysis of high penetration seismic lines (Cernobori et al., 1996; Doglioni et al. 1999; Finetti, 2005). None of these studies focuses on the outermost part of the CA system, i.e. the transition between the accretionary wedge and the Ionian abyssal plain, and we believe this is the reason why a major question remains unanswered: “is the CA subduction still active”?
The lack of seismicity along the subduction fault plane (with a characteristic shallow dipping thrust-type focal mechanism) can be explained by one of the following occurrences: 1) subduction has ceased; 2) subduction is active but aseismically, or 3) subduction is active and there is a large locked seismogenic zone. Diverse earthquake scenarios can be envisioned depending on which of these three hypotheses is taken into account. Understanding the present-day tectonics of the CA is thus important to understand the geological risk in central Mediterranean region
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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