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Folding within upper miocene deposists of Calabria Coast Range (Southern Italy)
No full textThe Tyrrhenian margin of northern Calabria is characterised by
discontinuous outcrops of Late Tortonian-Messinian clastic deposits.
These late Miocene successions, constituted by conglomerates,
clays, calcarenites and evaporitic arenites, lie unconformably over
the Calabrian igneous and metamorphic rocks. A detailed structural
study in a sample area, located around the village of Belvedere
Marittimo, allowed us to evaluate the deformation style of these
Upper Miocene deposits. These successions display a double noncoaxial
set of folds. The first compressive deformation shows an
Apenninic axis of shortening (NE-SW), while the second displays a
strike of folds comparable to Calabrian Arc structures (NE-SW).
These two sets of folds represent two distinct structural stages linked
to a progressive incorporation in the Calabrian Arc domain of portions
of the Apenninic Chain
Extensional detachment faulting on the tyrrhenian margin of the Southern Apennines contractional belt (Italy)
No full textThe tectonic evolution of the Campania margin during the late Pliocene–Pleistocene is characterized by extensional deformation coeval with the opening of the Marsili oceanic basin. The initial stages of stretching are represented in the analysed area by the development of low-angle normal faults that extended the belt in the same direction as the direction of spreading recognized for the oceanic basin. Detachment faulting was accompanied by the onset of magmatic activity and by major uplifts that resulted in the accumulation of thick conglomerate successions in the half-grabens that developed in the upper plate of the extensional detachment. Deformation continued during the Mid-Pleistocene with the formation of strike- slip and normal faults trending almost parallel to the spreading direction of the Marsili basin. These faults dissected the extensional detachment and promoted counter-clockwise block rotations about vertical axes, which accommodated the ESE-directed stretching of the Marsili basin and the consequent sinistral shear imposed on the southern Apennine chain. The development of a regional detachment fault along the Tyrrhenian margin of Campania explains the complex patterns of subsidence and uplift that characterize this area during the Pleistocene and fits well within the regional geodynamic framework of the southern Tyrrhenian Sea
Note illustrative della Carta Geologica d’Italia in scala 1:50.000, Foglio geologico n. 405 “Campobasso”
No full textProbabilistic approaches for assessing rainfall thresholds triggering shallow landslides. The study case of the peri-vesuvian area (Southern Italy)
Full text linkAsh-fall pyroclastic soil deposits covering steep carbonate slopes in the peri-Vesuvian area (southern Italy) are periodically involved in shallow landslides (about 700 events were recorded during the last three centuries, as reported by CASCINI et alii, 2008), triggered by intense and/or prolonged rainfall events, which evolve as catastrophic debris flows. In the last decades, many studies have been focused on estimating reliable relationships among the triggering of shallow landslides and the amount and duration of rainfall events, as well as the role played by antecedent soil hydrological conditions. Results of these studies have been expected to give information on temporal hazard to landslide onset to be used for setting a reliable early warning system. In this paper we present probabilistic approaches to assess rainfall thresholds triggering shallow landslides by classical empirical methods and to manage the uncertainties related to biases of data. At this scope, rainfall events related to the occurrence of debris flows along slopes of the Sarno and Lattari Mountains, known from chronicles of the last century, were analyzed by means of the empirical models of Intensity-Duration (I-D) (CAINE, 1980) and rainfall recorded in the day of the landslide occurrence (P) vs the antecedent cumulated rainfall (Pa) (CROZIER & EYLES, 1980). In order to limit and to assess uncertainties related to biases of rainfall data, a comparison with the regional probability model of high intensity rainfall, carried out in the framework of the VAPI Project (ROSSI & VILLANI, 1994) has been carried out. Moreover, rainfall data were processed by a bivariate logistic regression model resulting in the assessment of probability to landslide triggering, given an assumed rainfall event. The I-D empirical rainfall thresholds obtained by Caine model (1980) were compared to rainfall thresholds estimated by deterministic approaches (DE VITA et alii, 2013; NAPOLITANO et alii, 2016) showing a good match
Micropaleontological study on the Miocene Calcareous turbidite deposits of Faeto and Tufillo Formations (eastern sector of the Southern Apennine chain)
No full textIntegrated stratigraphy of Middle-Late Miocene synorogenic deposits of the Eastern Southern Apennine Chain: The San Bartolomeo Flysch
No full textThe present paper deals with the stratigraphic and biostratigraphic study of the middle-late Miocene thrust-top basin deposits of the San Bartolomeo Flysch, exposed north of Matese mountains and analysed during the geological survey of the sheet N° 405 Campobasso of the new Geological Map of Italy, 1:50.000 scale. The integrated study of calcareous nannofossils and planktonic foraminifera, based on the semi-quantitative distribution range of index species, revealed the presence of age-diagnostic assemblages which are comparable with those of different middle-late Miocene deep-marine sedimentary settings of the Mediterranean Basin. The biostratigraphic dataset suggests an early Serravallian – early middle Tortonian age. In terms of calcareous nannofossil biostratigraphy, the studied succession falls between the Last Occurrences of Sphenolithus heteromorphus and the First Occurrence of Discoaster bellus gr., corresponding to the MNN6 – MNN8 zone interval. In terms of planktonic foraminiferal biostratigraphy the studied sediments fall between the Last Occurrence of Globorotalia peripheroronda and the First Regular Occurrence of Neogloboquadrina acostaensis, corresponding to the MM6 p.p. - MMi10 p.p. zone interval. This study documents the applicability of the recent Mediterranean middle –late Miocene biozonations for the biostratigraphic study of siliciclastic synorogenic sediments, and challenges the most recent studies that dated the San Bartolomeo Flysch to the late Tortonian- early Messinian
Note illustrative della Carta Geologica d’Italia in scala 1:50.000, Foglio n. 467, Salerno
No full textIntegrated stratigraphy of Middle-Late Miocene synorogenic deposits of the Eastern Southern Apennine Chain: The San Bartolomeo Flysch.
No full textNote illustrative della Carta Geologica d'Italia in Scala 1:50.000, Foglio n. 431, Caserta est
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