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Phaistos Project. The linear section on the southeast slope of the Christos Effendi hill and the evolution of Phaistos in the Protopalatial period: a contextual reassessment
No full textDuring ten years of survey on the territory surrounding the palace of Phaestos, the "Project Phaestos", directed by Fausto Longo, under the aegis of the Italian Archaeological School of Athens and in collaboration with the Universities of Padua (Armando De Guio and Andrea Betto), Rome (Alessandro Greco) and Catania (Simona Todaro), has completed the survey (which also included some targeted trial excavations, restoration projects and the study of materials) of the territory surrounding the palace complex. The new data gathered allows the formulation of an updated picture of the 'urban phenomenon' of the settlement and its development from the Neolithic to the Hellenistic phases.
The primary purpose of this paper is to present a case study of particular interest for the understanding of 'urban development' of Protopalatial Phaestos: the linear section that opens along the Phaestos - Matala road on the southeast slopes of Christos Effendi, documenting the presence of an important housing area in situ.
The section will be examined in its topographical context (Alessandro Greco), from an archaeological and stratigraphic point of view (Andrea Betto), while the pottery excavated will also be presented (Simona Todaro and Laura Spampinato).
Our primary aim is to present a study of this strategic part of the “urban area” of Phaestos, to be integrated and compared with other better known “urban areas” of the site, such as Chalara and Haghia Photini, taking into account both the previous literature and the new theoretical models of development of the urban phenomenon in the Minoan Era (possibility of a unitary architectural/urban development project vs random progressive additions; study of the formation processes of the so-called foundation deposits and identification of precise "ritual and technological practices" and the possible application of these models in order to read and understand the urban phenomenon of Phaestos
A Cretaceous carbonate escarpment from Western Sicily (Italy): biostratigraphy and tectono-sedimentary evolution
No full textThe presence of a huge carbonate slope of Cretaceous age is recorded in some imbricated thrust sheets from the Maghrebian fold-and-thrust belt cropping out in northwesternmost Sicily (southern Italy). The sedimentological features of this escarpment, named as the Western Sicily Cretaceous Escarpment (WSCE), have been recently described. The present paper aims to provide a detailed bio- chronostratigraphic characterization of the different facies types that occur in the four lithostrati- graphic units spanning the whole slope depositional system. The detailed biostratigraphic analysis and correlation of a number of well-exposed sections allowed to differentiate eight informal biozones and to place the different studied sections, either from a single tectonic unit or from different ones, in a reliable chronostratigraphic frame. The integration of sedimentological and biostratigraphic data allowed in turn to time-constrain the main tectono-sedimentary events along the WSCE. In particular: i) the abrupt transformation from a carbonate ramp to a tectonically-controlled escarpment during the Berriasian- Valanginian; ii) the peak of tectonic instability leading to the emplacement of thick megabreccia bodies and repeated submarine volcanic emissions during the Aptian- Cenomanian; iii) the almost coeval increase in the skeletal supply in response to highstand shedding occurred during the Albian- Cenomanian; iv) the tectonic backstepping of the carbonate depositional system during the Senonian ending with the definitive shutdown of the carbonate factory in the late Maastrichtian. The acquired biostratigraphic dataset is in large part new for the Cretaceous of Sicily and provides information on the associations that populated a southwestern Tethyan carbonate platform during the Cretaceous
Facies Architecture and Evolution of a Cretaceous, Tectonically-Controlled, Carbonate Slope from Western Sicily (Italy)
No full textThe stratigraphic architecture of a Cretaceous carbonate slope from north western Sicily (Italy) has been reconstructed on the basis of detailed field sections. The wire cut walls of a number of quarries that extract the Cretaceous limestones as ornamental stones allowed the mapping of the stratal architecture and lithologies at various scales.
The vertical and lateral facies relationships in this about 1000 m thick depositional system account for a complex sedimentary dynamics along a carbonate platform escarpment that was strongly influenced by syn-sedimentary transtensional tectonics associated to magmatism. Although the original relationships with the carbonate platform were obscured by the Maghrebian orogeny, the source area of the clastic carbonates can be envisaged in the Panormide Platform, a paleogeographic unit Late Triassic to Eocene in age that crops out in northern Sicily.
The most common facies along the Cretaceous slope are mass transport deposits (MTD) with large (decimetre to metre-scale) elements of rudist limestone in a matrix of skeletal rudstone. They alternate to finer grained gravity flow deposits. Thin intercalations of Scaglia-type calcilutites (background sediments) point to occasional interruptions of the gravity flows.
The onset of the slope sedimentation occured in the Berriasian, as documented by the abrupt overlap of MTD with ellipsactinids/corals extraclasts on calpionellid wackestone. This event points to the conversion of a gentle ramp into a faulted escarpment that has favourded the collapse of the ellipsactinid-bearing extraclasts.
Two subsequent episodes of dissection of the slope are indicated by pillow basalt intercalations. Based on the benthic communities in the overlapping sediments the lava emissions could be constrained to the Aptian and Albian.
As recorded in many others carbonate platform-basin systems, the Cenomanian records a maximun downslope shedding of skeletal debris transported by turbidites and grain flows. A progressive decrease of the clastic supply along slope is recorded from Senonian onward as a consequence of the gradual drowning of the adjacent platform. However, the resedimentation pulses lasted at least up to the Maastrichtian thus indicating the perduration of a shallow water carbonate production in small isolated patches.
The study provides new insights for the understanding of the sedimentary dynamics along Cretaceous escarpments from western Tethys controlled by crustal extensional deformations
A benthic community biodiversity crisis documented on a Rhaetian carbonate succession from western Tethys (Sicily)
Full text linkA biodiversity crisis in the benthic communities was detected on Rhaetian stratigraphic horizons from a western Tethyan carbonate platform. The studied succession consists of a continuous Upper Triassic to Lower Jurassic peritidal limestone organized in shallowing upward cycles cropping out at Mt Sparagio (western Sicily). On the basis of abundance and diversity of the benthic communities in the subtidal facies, the studied section was divided into three informal units. Starting from the base, the Unit A contains very abundant and highly diverse fossiliferous assemblages of corals, very large megalodontoids (up to 40 cm) and large Triasina hantkeni (up to 1 mm) among other benthic foraminifera. Upward, Unit B is characterized by a reduction of biodiversity, abundance and shell size of megalodontoids that reach a dimension up to 15 cm and T. hantkeni is still present. The top of Unit B is recognized by a distinctive oolitic level. Up-section, after a barren interval rich in calcispherae, the absence of the benthic community documented in Units A and B and a bloom of the problematic alga Thaumatoporella parvovesiculifera characterize Unit C. Upward, the occurrence of rare specimens of the benthic foraminifer Siphovalvulina sp. indicates the gradual recovery of the Jurassic benthic community.
The stable isotope analyses (C, O and S) seem to correlate to the biodiversity crisis between Unit A and Unit B. In detail, a negative trend of δ18Ocarb values, corresponding to an increase in temperature, matches with the drastic reduction both in dimension and diversity of the megalodontoid families between Units A and B. Between Unit B and C, across the Triassic/Jurassic boundary, a strong positive peak of both δ18Ocarb and δ34SCAS marks the
biodiversity crises observed at the End Triassic Extinction, highlighting a close relationship between climatic changes and mass extinction events
Carbonate slope re-sedimentation in a tectonically-active setting (Western Sicily Cretaceous Escarpment, Italy)
No full textTectonic processes are widely considered as a mechanism causing carbonate platform margin instabilities leading to the emplacement of mass transport deposits and calciturbidites. However, only few examples establishing a clear link between tectonics and re-sedimentation processes are known from the lit- erature. The two-dimensional and three-dimensional wire-cut walls of hun- dreds of quarries extracting ornamental limestones (for example, Perlato di Sicilia) from the Western Sicily Cretaceous Escarpment in Italy expose a series of mass transport deposits. The depositional architecture, spatial facies distri- bution and sedimentary features of these deposits were studied in detail. Thin section analysis was used to define the microfacies characteristics and to determine the age of the re-sedimented limestones. Eleven facies types grouped into four facies associations were recognized that defined specific depositional processes and environments. The stratigraphic architecture of the slope was reconstructed using four composite facies successions based on the detailed analysis and correlation of the field sections. The palaeoslope orienta- tion was reconstructed based on the analysis of synsedimentary faults, slump scars and pinch-out geometries. The Western Sicily Cretaceous Escarpment was strongly influenced by synsedimentary transtensional tectonics in combi- nation with magmatic processes, as suggested by the presence of tuffites and pillow lava intercalations within the re-sedimented carbonate series. These volcanics point to a major role of crustal shear as a trigger for mass transport deposit emplacement. The facies distribution along the Western Sicily Creta- ceous Escarpment delivers new insights into the deformation processes accompanying the crustal extension of the Cretaceous western Tethys realm
Seismic-stratigraphy of Quaternary lowstand prograding wedges on the western margin of the Adventure Bank (central Mediterranean Sea)
Full text linkOn the shoreline positioning via remote sensing imagery: an isoradiometric approach
No full textEstimating the accurate position of the shoreline over time can be challenging.
We propose a new approach to delimit the shoreline from remotely sensed images
simply and accurately. This approach treats pixels as simultaneous radiometric
measurements and, by examining the distance between iso-radiometry lines,
assumes the shoreline in the position where the radiometric behavior changes more
suddenly. The analyses conducted applying this coastline extraction approach
underscore its significant flexibility. Specifically, the approach yields promising outcomes even if applied to a variety of different and dissimilar types of remotely sensed
products. Indeed, the approach’s intrinsic straightforwardness and low computational load qualify it as a promising tool for time-series production
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
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