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Neogene post-collisional evolution of the inner Northern Apennines: inferences from the upper Fiora and Albegna valleys, (Mt. Amiata geothermal area, southern Tuscany)
No full textThe southern Tuscany represents the internal portion of the
Northern Apennines. Its geological setting is particularly complicated
due to two main tectonic phases: a first compressional syn-collisional
phase (Late Cretaceous-Early Miocene) that led to nappe
building and km-scale tectonic features; a later extensional post-collisional
phase (Early Miocene-Pleistocene) led to uplift and unroofing
of the thickened crust is linked to the anticlockwise Apennine rotation
and Tyrrhenian Sea opening.
The upper valleys of the Fiora and Albegna rivers in southern
Tuscany represent a key area to reconstruct the post-collisional tectonic
and sedimentary evolution of this sector of the Apennine
chain. This area is characterized by a tectonic nappe stack built during
the syn-collisional phase, unconformably overlain by Miocene-
Pliocene depositional units, referable to a few sedimentary cycles.
The sedimentary-tectonic evolution for the study area, as recognizable
by field data, is the result of a sequence of different deformative
and depositional events. The compressive event (Early Miocene) led
to crust thickening and emplacement of the Ligurian units onto the
Tuscan Nappe. Later on, a first extensional event (Early-Middle
Miocene) developed low-angle normal faults. This event was responsible
of a strong tectonic elision and crustal thinning, forming the
«serie ridotta», characterized by a megaboudinage tectonic setting
and developing structural-morphological depressions, probably seat
of shallow-marine deposition. A second extensional event (Late
Miocene) developed west-dipping listric normal faults, increasing
the megaboudinage depressions. In the study area, the activity of
west-dipping normal faults caused the deformation of the tectonic
nappe stack with the development of regions with steep east-dipping
attitude of bedding. In these regions east-dipping normal faults
affected the steep dipping bedding, so to form structural depressions
in which tectonic delaminated slices, usually Ligurian units, were
emplaced. Moreover, such structural depressions represented also
the basins of the Late Miocene continental-marine sedimentation. A
third extensional episode (Pliocene) developed with high-angle normal
faults which dissected all the previous structures. During this
extensional event graben and half-graben basins formed, and the
Early Pliocene marine transgression with filling of deep elongated
basins parallel to the chain, developed
Physical stratigraphy and facies analysis of an outer carbonate ramp to basinal floor fan turbidite system: the Tertiary "Scaglia Toscana" Fm of the Chianti Mts. (Northern Apennines, Italy)
No full textGeology of the ‘Coltre della Val Marecchia’ (Romagna-Marche Northern Apennines, Italy)
Full text linkA detailed geological map at 1:50,000 scale of the Marecchia Valley and adjoining areas
(Northern Apennines, NA, Italy) is presented here. The Marecchia Valley represents a
geological ‘unicum’ for the NA and it has been the focus of scientific debate for a long time,
due to the occurrence in the area of the ‘Coltre della Val Marecchia (CVM)’, a complex stack
of allochthonous and semi-allochthonous units emplaced in a foredeep basin during the Late
Miocene to Early Pliocene. In order to clarify the geological evolution for this area, the
lithostratigraphic relationships and the tectonic framework have been studied, allowing
better understanding of the complex relationships between tectonics and sedimentation.
The main result has been a new evolutionary framework for this sector of the orogen during
the Late Miocene-Early Pliocene. Several new findings about the geological-structural setting
and stratigraphy, result from the geological map presented here. These are overall supported
by stratigraphic and tectonic evidence, which suggest time and modes of the CVM
allochthonous emplacement within the Messinian-early Pliocene foredeep successions.
Relationships between the allochthonous and autochthonous formations allowed recognition
of two different bodies in the CVM, gravitationally emplaced following different trajectories
and timing
A method for engineering-geological mapping: application to the Arezzo and Lucca provinces (Tuscany, Italy)
No full textLithological and geomechanical characters of outcropping rocks are relevant inputs for those applications involving geological issues. For instance, such information are used to implement spatial planning actions/rules influencing land use and transport infrastructures. The same data may also be used when mapping landslide susceptibility/hazard and preparing for landslide risk management. Many geomechanical classification systems for rock masses have been developed for engineering-geological applications (DEERE, 1963; BIENIAWSKI, 1973; BARTON et alii, 1974; HOEK, 1994). Nevertheless, these are site-specific systems or they are applied for specific engineering works (e.g. tunnels), so they are not fully adequate for continuous representations of engineering-geological properties over wide (map scale) areas. In this work, we describe the implementation of a GIS integrating lithological-geomechanical data collected in the field and laboratory with existing geological database to obtain an engineering-geological map at the scale of 1:10,000 for the provinces of Arezzo and Lucca (Tuscany, Italy). The study area is representative of different structural and lithologic settings within the Northern Apennines
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
Photogrammetry and laser scanning for analyzing slope stability and rock fall runout along the Domodossola–Iselle railway, the Italian Alps
No full textIn Italy, railways crossing the alpine valleys are a vital means of civil and commercial communications with the rest of Europe. The geomorphologic configuration and the climatic conditions, especially in winter and spring, can cause rock fall events resulting in railway service interruptions and damage to infrastructure and, in the worst case, to people. There were rock fall events at a slope adjacent to the Domodossola-Iselle railway, most recently in 2004.
This paper evaluates the stability of a mountain slope and maps rock fall hazards through the modeling of potential runout trajectories. Traditional geological, geomorphological and geo-engineering surveys were combined with data derived from digital terrestrial photogrammetry. Stereo photographic pairs of rocky outcrops in inaccessible areas were acquired from a helicopter. Data from photogrammetry, topographic measurements and laser scanning were then integrated to build a digital model of the slope, to characterize the rock mass and block geometry, and to define possible runout trajectories. The geomatic methods used have yielded oriented stereo-images, orthophotos and precise digital models of rocky wedges. Geometrical and structural characteristics of slopes, such as joint attitude, spacing and persistence, and block volumes, were also derived. The results were used together with a deterministic limit equilibrium method to evaluate slope stability. We assessed the probabilistic distribution of rock fall end points and kinetic energy along the rock falling paths and existing barriers, and created a hazard map based on the spatial distribution of trajectories, rock fall transit density and kinetic energy
Geothematic regional geodatabases for the compilation of geological maps in areas of relevant interest: The Coltre of Marecchia Valley (PU), the Iglesiente region (CA) and the Stazzemese area (LU)
No full textVariations 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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