1,720,961 research outputs found
Measure and modelling of factors controlling the bulk thermal conductivity of sedimentary rocks
No full textMultidisciplinary approach for outcropping and subsurface Permian-Cenozoic deepwater carbonates (Central Sicily): outcome for paleogeography of the Southern Tethyan continental margin
Full text linkAn integrated stratigraphic study of the outcropping and buried Permian-Cenozoic deep-water carbonate successions have been performed. These successions form some of the tectonic units, mostly buried beneath the Late Neogene sedimentary cover, in the fold and thrust belt of Central Sicily.
Three main successions, pertaining to the well known Lercara, Imerese and Sicanian domains, have been reconstructed on the basis of a detailed facies analysis, seismostratigraphic interpretation, biostratigraphy (mostly based on palynological data) and comparison between outcropping and subsurface deep-water sediments.
The main results reveal a continuous sedimentation of the deep-water Southern Tethyan Sicilian succession since the Permian to Cenozoic. In detail:
a) the Permian-Middle Triassic terrigenous and carbonate deep-water successions, outcropping or buried in the Cerda, Lercara-Roccapalumba and Sosio Valley regions, are well comparable to each other and represent the common substrate of the Mesozoic-Paleogene Imerese and Sicanian carbonate successions;
b) the Mesozoic-Paleogene deep-water carbonates, when compared among them, reveal the occurrence of different sedimentary successions (Imerese and Sicanian);
c) the Oligo-Miocene foreland basin terrigenous sediments (Numidian flysch) clearly differ from the coeval foreland hemipelagic to open-shelf carbonates.
The paleogeographic reconstruction envisages:
a) during the Permian-Triassic, a wide subsident continental rifting area, bordered by a shallow-water domain periodically supplying the basin with calciturbiditic to gravity flows sedimentation (rift stage of the Southern Tethyan margin);
b) during the Jurassic-Paleogene, two different deep-water basins developed in a context of a post-rift stage. The different sedimentation reflects the location of the Imerese and Sicanian basins, respectively, along adjacent rimmed shelf and stepped carbonate platform margins;
c) the Oligo-Miocene sedimentation reflects the afore-mentioned different location of the two deep-water domains. Flysch deposits suggest that the Imerese was located near an accretionary prism, differently the Sicanian open-shelf carbonates and marls developed on a still undeformed foreland
Thermal conductivity of sedimentary rocks and appropriate corrections for in-situ conditions
No full textPermian-Cenozoic deep-water carbonate rocks of the Southern Tethyan Domain. The case of Central Sicily
Full text linkWe present an integrated stratigraphy of the outcropping and
buried Permian-Cenozoic deep-water carbonate successions, forming
some of the tectonic units mostly buried beneath the Late Neogene
sedimentary cover in the fold and thrust belt of Central Sicily.
Three main successions, pertaining to the well known Lercara,
Imerese and Sicanian domains, have been reconstructed on the basis
of a detailed facies analysis, seismostratigraphic interpretation, bio -
stratigraphy (mostly based on palynological data) and comparison
between outcropping and subsurface deep-water sediments.
The main results reveal a continuous sedimentation of the deepwater
Southern Tethyan Sicilian succession since the Permian to
Cenozoic. In detail: a) the Permian-Middle Triassic terrigenous and
carbonate deep-water successions, outcropping or buried in the
Cerda, Lercara-Roccapalumba and Sosio Valley regions, are well
comparable to each other and represent the common substrate of
the Mesozoic-Paleogene Imerese and Sicanian carbonate successions;
b) the Mesozoic-Paleogene deep-water carbonates, when compared
among them, reveal the occurrence of different sedimentary
successions (Imerese and Sicanian); c) the Oligo-Miocene foreland
basin terrigenous sediments (Numidian flysch) clearly differ from
the coeval foreland pelagic to open-shelf carbonates.
The paleogeographic reconstruction envisages: a) during the
Permian-Triassic, a wide subsident continental rifting area, bordered
by a shallow-water domain periodically supplying the basin with calciturbiditic
to gravity flows sedimentation (rift stage of the Southern
Tethyan margin); b) during the Jurassic-Paleogene, two different
deep-water basins developed in a context of a post-rift stage. The different
sedimentation reflects the location of the Imerese and Sica -
nian basins, respectively, along adjacent rimmed shelf and stepped
carbonate platform margins
Palynostratigraphy and palynofacies of the Upper Triassic Streppenosa Formation (SE Sicily, Italy) and inference on the main controlling factors in the organic rich shale deposition
No full textThis paper focuses on the Upper Triassic Streppenosa Formation, penetrated by the Pachino 4 on-shore well, (Southern Sicily, Italy) in order to find stratigraphic age constrains and to reconstruct the paleoenvironmental evolution of this basin within the Upper Triassic palaeogeographic scenario of the western Tethys. Pachino 4 is one of the wells drilled by Eni Exploration and Production in the south-eastern Hyblean plateau with the purpose to better define the time and space distribution of reservoirs and source rocks in an area characterised by considerable subsidence and strong tectonic activity, balanced by high sedimentation rate. The Streppenosa Formation depocenter consists of a thick sequence (>2500 m) of organic rich shales, turbiditic limestones and marly limestones, grouped into three members (Lower, Middle and Upper). The well diversified microflora assemblages allow the dating of the upper part of the Lower Member and the Middle Member as Norian and the Upper Member as Rhaetian. The palynofacies variations across the Streppenosa Formation show significative changes in the relative abundances of the organic debris that, associated with the lithological and sedimentological features, allowed a reconstruction of the depositional facies successions and a hypothesis for the forcing mechanisms driving the black shale deposition. We considered that the deposition of the Streppenosa Formation occurred in an epeiric basin, under oxygen-depleted bottom waters, with different depth that varied through time in response to the sedimentation rates, eustatic sea level changes, and basin subsidence. The integration of palynofacies and lithofacies data suggest a crucial role for river runoff, responsible for water stratification and for primary productivity increase in the water column. The process was triggered by warmer and wetter climate conditions as documented in many Upper Triassic successions of the western Tethys realm
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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