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Reply to the comment on 'Sea-level control on facies architecture in the Cenomanian-Coniacian Apulian margin (Western Tethys): A record of glacio-eustatic fluctuations during the Cretaceous greenhouse?' by S. Galeotti, G. Rusciadelli, M. Sprovieri, L. Lanci, A. Gaudio and S. Pekar [Palaeogeography, Palaeoclimatology, Palaeoecology 276 (2009) 196-205]
No full textOrbitally modulated black shale deposition in the upper Albian Amadeus Segment (central Italy): a multi-proxy reconstruction
No full textOrbital tuning of a lower Cretaceous composite record (Maiolica Formation, central Italy)
Full text linkGlobal and regional factors responsible for the drowning of the Central Apennine Chattian carbonate platforms
No full textTwo stratigraphic sections of Central Apennine have been analyzed to interpret the factors responsible for the
Oligocene-Miocene drowning of the carbonate platforms. The Mt. La Serra section, representing the Northern sector of
the Latium-Abruzzi carbonate platform and the Opi section, representing the Eastern sector of the same domain have
been investigated for facies and stable isotope characteristics (Brandano et al., in press).
Important positive δ13C shifts have been recorded at the Oligocene-Miocene boundary in both sections. These shifts
range from -0.34‰ 1 m below the top of the Chattian to +0.85‰ in the Aquitanian spongolitic marls in the Mt. La Serra
section, and from +0.05‰ to +0.60‰ in the Aquitanian spongolitic interval of the Opi section. These facies and Cisotope
variations reflect an increased productivity of surface seawater and correspond to changes from a middle
carbonate ramp to outer ramp depositional environment. This drowning event is recorded not only in Apennine
platforms, but also in other Mediterranean platforms such as in southern Apulia, Sicily and Malta, and outside the
Mediterranean Basin, (e.g., the Carribbean area).
We propose two possible major factors responsible for this drowning event: the Mi-1 event, and the volcanic activity
peak developed in the Central-Western Mediterranean during the Chattian-Burdigalian interval. The Mi-1 glacial
maximum (~24-23.5 Ma) may have had a strong influence on the drowning event on a global scale, as it triggered a
weathering and continental runoff increase, which sustained eutrophic conditions and water turbidity. The development
of a widespread subduction-related igneous activity in the Western Mediterranean during the Latest Oligocene-Early
Miocene may have had even a stronger effect on the carbonate production of the Apennine platforms. Arrival of
volcanic material such as airborne ash can have increased water turbidity, reducing light penetration and, above all,
producing a huge fertilization effect of the euphotic marine environments, bringing micro- and macronutrients to the
surface waters. A second consequence is an increase of the SiO2 seawater content, thus favouring siliceous organisms.
Last not least, it has to be mentioned that the propellants for explosive volcanism are CO2, H2O and sulphur. A raise of
both atmospheric and marine CO2 concentration could have led to a greenhouse effect and, thus, to an additional
increase of weathering and runoff, and also to a decrease of seawater pH and a reduction of carbonate ions
concentration, favouring calcite-dominated skeletal assemblages (heterozoans) and, above all, siliceous productio
Perturbation at the sea floor during the Paleocene-Eocene Thermal Maximum: Evidence from benthic foraminifera at Contessa Road, Italy.
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ODP Leg 160, Site 936/A tephra layers: new geochemical and chronological data of Quaternary explosive volcanic events.
No full textGoing 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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