1,720,982 research outputs found
New information from "old" seismic lines: An updated geological interpretation from the re-processing of the CROP line M-2A/I (Bonifacio Straits) at shallow depths
No full textThe shallowest part (about 3 sec two-way traveltime) of the CROP line M-2A/I, acquired during 1991 in the Bonifacio Strait (between Corsica and Sardinia), was reprocessed to improve its geological interpretation. The original target of the M-2A/I profile was the entire crust and therefore the shallowest part was only partially interpreted. In this context, the re-processing procedure was carried out to improve the signal-to-noise ratio and the resolution at shallow depth. The geological interpretation of the reprocessed data aimed at the reconstruction of the sedimentary succession and the contact with the underlying Hercynian basement. The M-2A/I seismic profile was interpreted identifying diverse seismic facies, in relation with the geological units outcropping to the north (in Corsica) and to the south (in Sardinia) of the seismic profile. The study supports the existence of a thick Mesozoic succession, onlapping the Hercynian basement, preserved below the Cenozoic succession in the Asinara Gulf, suggesting that the Nurra succession continues northward in the offshore. The Mesozoic succession is bordered by a major, east-dipping normal fault, east of the Asinara Island ridge. The faults recognized in the seismic profile indicate a prevailing strike-slip/transtensional tectonics, questioning the role of compressional tectonics suggested in a previous interpretation. The obtained results also indicate the potential of re-processing of existing seismic profiles, whose interpretation can be significantly updated thanks to the development of new processing procedures and to the continuous upgrade of the regional geological knowledge
Does compaction-induced subsidence control accommodation space at the top of prograding carbonate platforms? Constraints from the numerical modelling of the Triassic Esino Limestone (Southern Alps, Italy)
Full text linkThe demise of the high-relief, steep-slope, prograding Ladinian-Early Carnian carbonate platforms of the
Esino Limestone (Central Southern Alps of Italy) is marked by subaerial exposure of the platform top
associated with different erosional (mainly karst-related), depositional and diagenetic processes (Calcare
Rosso). The exposure-related deposits consist of three major facies associations: 1) residual soils with
thin lenses of conglomerates with black pebbles, and, locally, weathered vulcanites; 2) chaotic breccia
lenses irregularly distributed in the uppermost part of the Esino Limestone carbonate platform, interpreted as collapse breccias in karstic setting: 3) inter-supratidal carbonate cycles with dissolution and
development of paleosols and tepee structures.
Facies distribution follows the sub-environments of the underlying Esino Limestone. Facies 1 and 2
typically characterize the core of the platform, covering the underlying inner platform facies. Facies 3
instead develops toward the edge of the platform, above reef-upper slope facies of the prograding facies
of the Esino Limestone. The thickness of facies 3 decreases toward the core of the platform. Facies distribution reflects differences in the accommodation space and sedimentary processes from the rim
(highest accommodation, favouring the deposition of peritidal-supratidal carbonates) to the core
(reduced accommodation, causing pedogenesis and karstification) of the carbonate system.
The observed thickness changes may be controlled by different factors: 1) syndepositional tectonics, 2)
subsidence induced by magmatic activity or 3) differential subsidence controlled by the stratigraphic
architecture of the Esino Limestone platform and adjoining basins. As evidence of tectonics was not
observed and the presence of volcanic bodies is only documented tens of km away from the study area,
the scenario involving the creation of accommodation space by compaction of the basinal sediments
(resedimented, fine-grained calciturbidites) during the progradation of the carbonate platform is here
investigated. Numerical modelling was performed to verify the compatibility of compaction-induced
subsidence with the observed depositional architecture. The models were built to simulate the architectural evolution of the platform by progressively adding layers from deepest to shallowest, while
compacting the underlying sediments, in order to evaluate compaction-induced subsidence (and accommodation space for the Calcare Rosso) after the deposition of the youngest platform strata. Modelling
results allow us to conclude that the wedge geometry of the Calcare Rosso, deposited on top of the
extinct Esino carbonate platform, can be explained by subsidence controlled by compaction of the basinal
sediments present below the early-cemented, fast prograding platform slope deposits
Fault zone evolution and fluid circulation within active extensional faults in carbonate rocks
No full textStructural and geochemical methods applied to the seismically-active extensional Tre Monti Fault (central Apennines, Italy) were used to develop a conceptual evolutionary model of seismic faulting with fluid involvement for shallow (≤ 3 km depth) extensional faults in carbonate rocks. The relative chronology of these structures was reconstructed through cross-cutting relationships and cathodoluminescence analyses. C- and O-isotope data from different generations of fault-related mineralizations show a shift from marine- to meteoric-derived fluid circulation during exhumation from 3 to ≤1 km depths and concurrent fluid cooling from ~68 to <35 °C. Between ~3 km and ~1 km depths, impermeable barriers within the sedimentary sequence created a semi-closed hydrological system, where marine-derived fluids circulated within the fault zone at temperatures between 60° and 75°C without any mixing with meteoric-derived fluids. During fault zone exhumation at depths ≤ 1 km and temperatures <35 °C, the hydrological circulation became open and meteoric-derived fluids progressively infiltrated and circulated within the fault zone. The presence of low-permeability clayey layers in the sedimentary sequence contributed to control the type of fluids infiltrating into the fault zone. These results can foster the comprehension of fault-related fluid circulation within seismogenic faults at shallow depths in carbonate rocks of other fold-thrust belts involved in post-collisional seismogenic extensional tectonics
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
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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