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Sagaria cilentana gen. et sp. nov. A new Angiosperm Fructification from the Middle Albian of Southern Italy
No full textA single specimen of a new fossil angiosperm, Sagaria cilentana gen. et sp. nov., has been recovered from
limestones of the ‘‘plattenkalk’’ of the Middle Albian at Monti Alburni, near Petina, Campania, Italy.
Associated fossils include Pagiophyllum sp., Podozamites sp. and Zamites sp. The angiosperm has a main
axis approximately 8 cm long with three attached leaves and a distal cyme bearing three fructifications.
The fructifications display divided distal tips indicating three - four lobes. Four cm from the base,
underneath the main axis, there is a lobed structure, presumably a leaf. An unattached leaf near the
specimen is in a position that suggests that it comes from the same plant. The leaf has an elongate
petiole, obtuse base and on the right side of the lamina are three lobes. Affinities are uncertain but show
similarities in overall morphology to basal eudicots, especially Ranunculaceae
A new terrestrial plant-rich Fossil-Lagerstätte from the middle Cenomanian (Late Cretaceous) of the Apennine Carbonate Platform (Magliano Vetere, southern Italy): Depositional and palaeoenvironmental settings
No full textWe describe a new terrestrial, plant-rich Fossil-Lagerstätte discovered at Magliano Vetere (Campania region,
S Italy) in the middle Cenomanian of the Apennine Carbonate Platform. The deposit, 1.42 m thick, is made up
of a thin-bedded interlayering of evenly laminated dolomicrites, lenticular dolorudites and carbonaceous
seams, which contain well-preserved remains of terrestrial plants yielding cuticles and minor fishes. This study
focuses on plant remains, to provide systematical, taphonomical and palaeoenvironmental considerations;
nevertheless, a preliminary analysis carried out on fossil fishes has led to the identification of pycnodontids
and teleosts. The Fossil-Lagerstätte retains sterile foliage-bearing shoots with epidermal features belonging to
the genus Frenelopsis of the extinct conifer family of the Cheirolepidiaceae. Plant remains possibly represent a
stable biotope, as floral composition displays no variation along the deposit. Nevertheless, episodes of harsh
environmental conditions occurred as demonstrated by a fish mortality event and Ca-sulphate evaporite
precipitation. Taphonomical considerations and sedimentological evidence fromthe encasing sediments suggest
a parautochthonous deposition of fossil plants in a supratidal/intertidalmudflat, including a salt-marsh that was
characterised by a restricted sea-water circulation, deposition of primary dolomite and episodical wildfires. The
presence of xeromorphic features in Frenelopsis from Magliano Vetere could represent an adaptation to haline
environmentwhichwas subjected to microtephra supply froma distant, orogenic volcanism. The facies evolution
of the studied Fossil-Lagerstätte records a rapid regressive and a following slower transgressive trend, and
constitutes the lowermost portion of a ~20 m thick interval characterised by several dolomitic plattenkalk,
up to 1.50 m thick, which are separated by cyclically stacked peritidal limestones. We infer that: 1) the ~20 m
thick, Plattenkalk-bearing interval represents a Sequence Boundary Zone in the stratigraphical record of the
middle Cenomanian ApCP; 2) Frenelopsis thrived at the verge of an arid–semiarid climatical phase during a
major pulse of relative sea-level fall
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
Osservazioni geologiche e paleontologiche su di un orizzonte a piante fossili del Cenomaniano di Monte Chianello (Appennino meridionale)
No full textA new calcareous-dolomitic horizon of a platy-dolomite type (sensu BERNIER, 1994), containing the remains of a Cenomanian continental palaeoflora, is reported. The platy-dolomite crops out in the Mount Chianello carbonate ridge (sheet tav. I.G.M. 1:25.000, 198 IT S.W. - Castel San Lorenzo), dominating the village of Magliano Vetere (SA).
This ridge is a deformed part of a Mesozoic-Cenozoic platform (campano-lucana platform in D'ARGENIO et alii, 1973; apenninic platform in MOSTARDINI & MERLINI, 1986).
A 200 m thick interval of the sequence has been sampled in order to date this platy doloinite. On the basis of facies, it has been divided into four intervals which are, from bottom to top:
a) 50 m stromatolitic dolomite and limestones below the platy dolomite, showing the sedimentological features of a restricted lagoonal environment in an inner carbonate platform. Among the microfossils, Sellialveolina viallii COLALONGO, Nezza-zata simplex OMARA, Pseudolituonella reicheli MARIE, Biplanata peneropliformis HAMAOUI & SAINT-MARc and Pseudorhapydionina dubia (DE CASTRO) are present. This fossil assemblage indicates in age ranging from the base of the Cenomanian up to the middle Cenomanian (DE CASTRO, 1991).
b) 70 m thin-bedded dolomite and dolomitic limestones of which the typical platy dolomite facies constitutes 40 m in which sets of millimetre-scale laminae are frequently present and often contain terrestrial floral remains on the laminae surfaces. The fossi-liferous horizon is ascribed to the middle-upper Cenomanian by, the presence of Nezzazata simply OMARA, Biconcava bemori HAMAOUI & SAINT-MARC, Biplanata peneropliformis HAMAOUI & SAINT-MARC Chrysalidina gradata D'ORBIGNY, Pseudorhapydionuna dubia (DE CASTRO), Pseudorhapydionina laurinensis (DE CASTRO). The sedimentological features of the platy-dolomite and fossil flora content suggest deposition in a tidal flat under upper- intertidal-supratidal conditions and, in particular, in an algal-marsh environment often exposed to dessication and storms, located close to a coastal area with primeval Angiosperms and Conifers. The first palaeontolological studies on this continental flora, allow its to ascribe some fossils to Sapindopsis sp..
c) 42 m limestones and bioturbated dolomite which, marks a drastic change in the environmental and sedimentological conditions on the carbonate platform, with heavily bioturbated bioderrital material (namely fragments of Rudists), often in massive lavers, proving a swift transition to deeper open marine conditions. In particular, the first 18 metres of this interval have many traces of Thalassinoid bioturbation. The tracks and burrows give an unmistakable appearance to the rocks and make this an important marker horizon in the whole ridge of Mount Chianello-Mount Vesole. Because of the presence in thin section of Dicyclina sp., Cisalveolina fraasi (GLMBEL) and Pseudorhapydionida casertana (DE CASTRO), a late Cenomanian age is assigned to this interval.
d) 43 m of limestones and dolomite. The sedimentological features indicate an open carbonate platform emironment often with coarse biodetrital elements and in the upper part, a tendency to the emersion. This interval has been assigned to the Turonian by the presence of Murgeina apula (LUPERTO-SINNI). Biconcava bentori HAMAOUI & SAINT MARC and small Moncharmontia apenninica (DE CASTRO).
In conclusion, the above observations show that the sequence including the platy dolomite of Magliano Vetere, ranges in age from the Lower Cenomanian to the Turonian.
The flora of the platy dolomite is Middle Cenomanian in age and reflects an upper intertidal-supratidal environment.
The plant remains ascribed to the genus Sapindopsis constitute the first Italian finding of this type and fit well with a shallow marine environment close to a coast line.
The studied sequence documents peritidal or paralic environments with a restricted water circulation in the Lower Cenomanian, with a strong tendency to stagnation in the Middle Cenomanian (platy dolomite). The restricted conditions change drastically in the Upper Cenomanian with its bioturbated rudist fragment-rich horizons.
As other similar horizons in the Mesozoic carbonatic sequences of the Southern Apennine (BRAVI, 1995), the platy dolomite of Magliano Vetere seems to fit well, due to its age, with a marked eustatic sea level minimum in the Middle Cenomanian; tis minimum is recognizable in the 3degrees order eustatic curve of HAO el alli (1987).
As a final considerations, it could be said that the studied sequence is relevant to two important currents of research:
The analysed stratigraphic imerval, because of its quality and thickness, is particularly appropriate for studies of the enironmental and ecological changes in carbonate shallow water platforms during the global anoxic event at the Cenomanian-Turonian (C/T) boundary, at present the object of important research (ERBA et alii; 2001; FORSTER et alii, 2001: KOLONIC et alii, 2001, WALSWORTH-BELL et alii, 2001). In the succession studied the Cenomanian Turonian boundary is located between the intervals c and d (see fig. 3). This transition represents a short period during which, in the neritic realm, strong environmental change and an important evolutionary overturn are associated.
In the hydrocarbon context, the main source rocks in the Italian sedimentary sequences are constituted by organic-rich intervals deposited in shallow carbonate platform environments or in deep water interplatform basinal settings (KATZ et alii, 2000). Although similar rocks are present in a number of different stratigraphic levels, only those in the Upper Triassic-Lower Triassic (accumulations of Malossa, Rospo and Gela), Middle Triassic (accumulation of Villafortuna) and Upper Cretaceous (Monte Alpi) are at present known to have generated oil. Detailed geochemical studies (KATZ et alii, 2000) indicate that there is a sharp contrast in the stable isotope composition of the organic matter contained in the different Italian carbonate source rocks. The Triassic and Toarcian organic matter is isotopically light (delta C-13(bitumen) <-26%), while that of Cretaceous and Oligo-Miocene age is isotopically heavy (delta C-13(bitumen) heavier than 26%). From this distinction two different oil populations are derived, associated with carbonate source rocks. These are an isotopically light population which includes the oils at Rospo Mare, Malossa and the oil at Maiella; and an isotopically heavier Population, including the oils at Monte Alpi, Bagnolo and the Trarnutola seep (KATZ et alii, 2000).
In this perspective, the deposit studied could constitute a source rock for oil plays in the Southern Apennines, for similar anoxic Middle Cenornanian thin-laininated facies have been frequently observed by one of us (S. Bravi, Carg Project) in other sectors of the chain (eg.: M.te Toberma, province of Salerno)
The Early Cretaceous flora from Profeti, Caserta, Southern Italy
No full textAn examination has been carried out of the floral assemblage from the lower–middle Aptian locality of Profeti village, near Caserta, Campania, Southern Italy. The assemblage consists of vegetative and reproductive remains belonging to conifers and to isolated angiosperm leaves. The genera Brachyphyllum, Araucarites, Nageiopsis, Frenelopsis, and Cupressinocladus? are documented. Macroscopical and cuticular analyses with light and scanning electron microscopes enable the description of a new cheirolepidiacean species: Frenelopsis profetiensis. The assemblage shows the classical features of xeromorphy. Sedimentological analysis together with macroscopical and cuticular features of the studied samples, suggests a subtropical climate, probably under semi-arid or arid conditions. The floristic composition shows close affinities with other coeval Tethyan communities, but no similarity with the Gondwanan flora
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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