1,720,976 research outputs found
New constraints on Neogene counter-clockwise rotation of Adria relative to Europe
Get PDFThe Adriatic microplate (Adria) is a key player in the geodynamics of Alpine-Mediterranean belts because of its
location between two converging plates, Europe and Africa. Most of Adria has been subducted and is presently
surrounded by deformed margins comprising the Alps, Apennines, Dinarides and the Calabrian Arc. The Alps-
Apennines and Alps-Dinarides junctions are marked by switches in subduction polarity, with Adria being the
indenting upper plate in the Alps and the lower plate in the Apennines and Dinarides. Reconstructing Neogene
motion and rotation of Adria is therefore key to understanding how such contrasting orogenic styles develop within
a similar convergent tectonic regime.
We propose a new kinematic reconstruction that balances shortening and extension in the northern Apennines; it
reveals that Adria rotated counter-clockwise as it subducted beneath the European Plate to the west and to the east,
while indenting the Alps to the north
One microplate - three orogens: Alps, Dinarides, Apennines and the role of the Adriatic plate
Get PDFThe motion of the Adriatic microplate with respect to the Eurasian and African plates is responsible for the
Mesozoic to present tectonic evolution of the Alps, Carpathians, the Dinarides and Hellenides as well as the
Apennines. The classical approach for reconstructing plate motions is to assume that tectonic plates are rigid,
then apply Euler’s theorem to describe their rotation on an ideally spherical Earth by stepwise restorations of
magnetic anomalies and fracture zones in oceanic basins. However, this approach is inadequate for reconstructing
the motion of Mediterranean microplates like Adria, which, at present, is surrounded by convergent margins and
whose oceanic portions have by now been entirely subducted. Most constraints on the motion of the Adriatic
microplate come either from palaeomagnetics or from shortening estimates in the Alps, i.e. its northern margin.
This approach renders plate tectonic reconstructions prone to numerous errors, yielding inadmissible misfits in the
Ionian Sea between southern Italy and northern Greece. At the same time, Adria’s western and eastern margins
in the Apennines and in the Dinarides have hitherto not been appropriately considered for improving constraints
on the motion of Adria. This presentation presents new results of ongoing collaborative research that aims at
improving the relative motion path for the Adriatic microplate for the Cenozoic by additionally quantifying and
restoring the amount of shortening and extension in a set of geophysical-geological transects from the Tyrrhenian
Sea, the Apennines and the Dinarides. Already now, our approach yields an improved motion path for the Adriatic
microplate for the last 20 Ma, which minimizes misfits in previous reconstructions.
The currently largest challenge in our reconstructions is to reconcile amount and age of shortening in the Dinarides
fold-and-thrust belt. For one thing, we see good agreement between the cross-sectional length of subducted
material (c. 135 km, estimated from p-wave tomographic models) and shortening in the external carbonate
platform of the Dinarides thrust belt (c. 127 km, from balanced cross sections). However, most of the thrust belt
shortening is of Palaeogene age, which is difficult to bring into agreement with the fact that most of the subduction
observed in tomographic models is most likely of Neogene age. This suggests that a substantial amount of
Neogene crustal shortening must have been accommodated in the internal parts of the Dinarides fold-and-thrust
belt rather than along its front. More field studies are therefore badly needed to obtain a better understanding
of the timing of individual faults and their role during the Neogene evolution of the NE margin of the Adriatic plate
Faulting, basin formation and orogenic arcuation at the Dinaric–Hellenic junction (northern Albania and Kosovo)
Get PDFThe Dinaric–Hellenic mountain belt bends where two fault systems transect the orogen: (1) the dextral Shkoder-Peja Transfer Zone (SPTZ), active sometime between the Late Cretaceous and middle Eocene; (2) the Shkoder-Peja Normal Fault (SPNF), which accommodated NW–SE directed orogen-parallel extension. The SPTZ dextrally offsets the Dinaric–Hellenic nappes by ~ 75 km, a displacement attributed to reactivation of an Early Mesozoic rift transfer zone in the Adriatic margin during Paleogene subduction of the Pindos Ocean. This subduction involved an initial counter-clockwise rotation of the Hellenides with respect to the Dinarides around a pole at the NW end of the Budva–Krasta–Cukali–Pindos Basin. The SPNF overprints the SPTZ and is a composite structure comprising five fault segments: four of them (Cukali–Tropoja, Decani, Rožaje, Istog) were active under ductile-to-brittle conditions. They downthrow the West Vardar Ophiolite in the hanging wall. The Cukali–Tropoja and Decani segments exhume domes with anchizonal-to-greenschist-facies metamorphism in their footwalls. These structures formed during a first-phase of extension and clockwise rotation, whose Paleocene age is constrained by cross-cutting relationships. A second extensional phase was accommodated mainly by the fifth (Dukagjini) segment of the SPNF, a subsurface normal fault bordering syn-rift, mid-late Miocene clastic and lacustrine sediments in the Dukagjini Basin (DB) that are sealed by Plio-Pleistocene strata. This later phase involved subsidence of Neogene basins at the Dinaric–Hellenic junction coupled with accelerated clockwise oroclinal bending. The driving force for clockwise rotation is thought to be bending and rollback of the untorn part of the Adriatic slab beneath the Hellenides
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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