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Vegetational history across the middle Pleistocene Transition in the central Mediterranean (Crotone Basin, Calabria, Southern Italy). Geophysical Research Abstract,
No full textVegetational history across the middle Pleistocene Transition in the central Mediterranean (Crotone Basin, Calabria, Southern Italy). Abstract, in: Early/Middle Pleistocene Transitions: the Land/Ocean evidence, Cambridge, 2003
No full textA revision of the stratigraphy and geology of the south-western part of the Crotone Basin (South Italy)
No full textThe Crotone Basin, located on a stack of nappes piled up during the late Paleogene-Neogene, formed in the late Neogene to Quaternary as a forearc basin of the Ionian arc-trench system. The process of slab rollback caused rapid trench migration, resulting in an extensional- transtensional regime persisting most of the time in the forearc area. The late Neogene tectonic evolution was strongly influenced by a NW-directed fault system, interpreted as basement wrench faults leading to partitioning of the basin into separate sub-basins subject to differential subsidence and mutual displacements. Major sequences identified in the area are regarded as tectono-strati- graphic sequences (TSS). The first of them was laid down in the late Serravallian (?) – Tortonian – early Messinian, during the basin opening stage and is bounded at the top by an erosional unconfor- mity, which may be correlated with the well-known intra-Messinian event of the Mediterranean Salinity Crisis. The second TSS, of mid- dle to late Messinian age, is characterized by strongly syntectonic deposits mostly derived from cannibalization of the lower Messinian succession, first infilling extensional troughs, then involved in an episode of sinistral transpression along the NW-trending fault sys- tem, which generated local overthrusts, sealed by a late Messinian erosional unconformity. The Messinian tectonics probably reflects the interplay between the processes linked to the kinematics of the Calabria block and those triggered by the Salinity Crisis. The ero- sional unconformity is overlain by widespread coarse fluvial con- glomerates, which are the first onlapping term of the third TSS, rep- resented by uppermost Messinian to lower Zanclean deposits, laid down in an extensional-transtensional regime. This TSS was closed by an important late Zanclean episode of dextral transpression along the NW-trending fault system, leading to inversion of the former basins, and limited SW-verging thrusts on fault-restraining bends. The unconformity sealing the structures has a clear expression in the northern, marginal part of the Crotone Basin and correlates down- basin with a conformable surface. The fourth TSS is characterized by a long-lasting phase dominated by extension-transtension, lead- ing to high subsidence rate during the latest Zanclean to Early Plei- stocene, and accommodating a thick succession of slope mudstones including clusters of diatomaceous bands mostly in the D. tamalis and D. brouweri Zones. In the northern part of the Crotone Basin two phases of drowning separated by an uplift pulse at ca. 2.55 Ma can be recognized, the second of which was a dramatic collapse, between 2.3 and 2.1 Ma. The fifth TSS is bounded at the base by an unconformity at the transition between «large» and «small» Gephy- rocapsa Zones, i.e. at around 1.1-1.2 Ma, correlating basinwards with a conformable surface. The unconformity is erosional and locally angular in the marginal part of the basin, where it seals struc- tures generated by a contractional event documented also elsewhere in the Calabria block. This event, which is accompanied by a strike- slip component, is inferred to be coeval to the Lower Pleistocene important transpressional episode along the Pollino shear system, which led to release of the Calabria block from the southern Apennines. The fifth TSS is characterized by resumed dextral transten- sion in the Middle Pleistocene along right-stepping NW-trending faults. This episode generated minor pull-apart sub-basins, showing spectacular growth structures in their infilling successions, which developed with shoaling trend up to inferred Marine Isotope Stages 9-8. The onset of shoaling trend was diachronous, being remarkably younger in the southern sub-basin. In the late Middle Pleistocene to Recent times extensional tectonics was dominating, accompanied by local gravity gliding towards the Ionian Sea, arguably triggered by increase in topographic gradient following hinterland uplift, and implying the activation of a linked, thin-skinned extensional and contractional NE- to NNE-directed fault system, with detachment surface possibly soling into Messinian evaporitic-mudstone deposits. It is concluded that the geologic evolution of the investigated forearc area was characterized by an alternation of long-lived stages of extension-transtension expressed by prolonged subsidence preceded by uplift pulses, and short-lived episodes of contraction-transpres- sion. Major drowning episodes in the forearc area are thought to be coeval to the main phases of spreading in the Tyrrhenian basin
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
Chronology of the Middle-Upper Pliocene succession in the Strongoli area: constraints on the geological evolution of the Crotone Basin (Southern Italy).
No full textThe aim of this study is to reconstruct the evolution of the Strongoli area, a critical sector of the Crotone Basin (Calabria, Southern Italy), where a thick Middle-Upper Pliocene marine succession is present. The Strongoli succession shows prominent changes in the sedimentary environment that are partly forced by tectonics. Major tectonostratigraphic events have been recognized that might correlate with spreading pulses in the back-arc Tyrrhenian Sea. In particular, we demonstrate that a dramatic basinal collapse at c. 2.3 Ma correlates with the so-called 'Calabrian transgression' Auctorum and is close in age to the oceanization of the Marsili Basin
A revision of the stratigraphy and geology of the south-western part of the Crotone Basin (South Italy)
No full textThe Crotone Basin, located on a stack of nappes piled up during
the late Paleogene-Neogene, formed in the late Neogene to Quaternary
as a forearc basin of the Ionian arc-trench system. The process of slab
rollback caused rapid trench migration, resulting in an extensional-transtensional
regime persisting most of the time in the forearc area.
The late Neogene tectonic evolution was strongly influenced by a NW-directed fault system, interpreted as basement wrench faults
leading to partitioning of the basin into separate sub-basins subject
to differential subsidence and mutual displacements. Major
sequences identified in the area are regarded as tectono-stratigraphic
sequences (TSS). The first of them was laid down in the late
Serravallian (?) – Tortonian – early Messinian, during the basin
opening stage and is bounded at the top by an erosional unconformity,
which may be correlated with the well-known intra-Messinian
event of the Mediterranean Salinity Crisis. The second TSS, of middle
to late Messinian age, is characterized by strongly syntectonic
deposits mostly derived from cannibalization of the lower Messinian
succession, first infilling extensional troughs, then involved in an
episode of sinistral transpression along the NW-trending fault system,
which generated local overthrusts, sealed by a late Messinian
erosional unconformity. The Messinian tectonics probably reflects
the interplay between the processes linked to the kinematics of the
Calabria block and those triggered by the Salinity Crisis. The erosional
unconformity is overlain by widespread coarse fluvial conglomerates,
which are the first onlapping term of the third TSS, represented
by uppermost Messinian to lower Zanclean deposits, laid
down in an extensional-transtensional regime. This TSS was closed
by an important late Zanclean episode of dextral transpression along
the NW-trending fault system, leading to inversion of the former
basins, and limited SW-verging thrusts on fault-restraining bends.
The unconformity sealing the structures has a clear expression in the
northern, marginal part of the Crotone Basin and correlates downbasin
with a conformable surface. The fourth TSS is characterized
by a long-lasting phase dominated by extension-transtension, leading
to high subsidence rate during the latest Zanclean to Early Plei -
stocene, and accommodating a thick succession of slope mudstones
including clusters of diatomaceous bands mostly in the D. tamalis
and D. brouweri Zones. In the northern part of the Crotone Basin
two phases of drowning separated by an uplift pulse at ca. 2.55 Ma
can be recognized, the second of which was a dramatic collapse,
between 2.3 and 2.1 Ma. The fifth TSS is bounded at the base by an
unconformity at the transition between «large» and «small» Gephyrocapsa
Zones, i.e. at around 1.1-1.2 Ma, correlating basinwards
with a conformable surface. The unconformity is erosional and
locally angular in the marginal part of the basin, where it seals structures
generated by a contractional event documented also elsewhere
in the Calabria block. This event, which is accompanied by a strikeslip
component, is inferred to be coeval to the Lower Pleistocene
important transpressional episode along the Pollino shear system,
which led to release of the Calabria block from the southern Apennines.
The fifth TSS is characterized by resumed dextral transtension
in the Middle Pleistocene along right-stepping NW-trending
faults. This episode generated minor pull-apart sub-basins, showing
spectacular growth structures in their infilling successions, which
developed with shoaling trend up to inferred Marine Isotope Stages
9-8. The onset of shoaling trend was diachronous, being remarkably
younger in the southern sub-basin. In the late Middle Pleistocene to
Recent times extensional tectonics was dominating, accompanied by
local gravity gliding towards the Ionian Sea, arguably triggered by
increase in topographic gradient following hinterland uplift, and
implying the activation of a linked, thin-skinned extensional and
contractional NE- to NNE-directed fault system, with detachment
surface possibly soling into Messinian evaporitic-mudstone deposits.
It is concluded that the geologic evolution of the investigated forearc
area was characterized by an alternation of long-lived stages of
extension-transtension expressed by prolonged subsidence preceded
by uplift pulses, and short-lived episodes of contraction-transpression.
Major drowning episodes in the forearc area are thought to be
coeval to the main phases of spreading in the Tyrrhenian basi
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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