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The heterogeneity of the suboceanic mantle source is usually defined based on MORB lateral geochemical variability. However, tackling short-scale variability is partially hampered by the large extent of mixing occurring during melt extraction and magma chamber processes. We identified a singular region of the Mid Atlantic Ridge at the eastern Romanche Ridge-Transform Intersection (Equatorial Atlantic) characterized by an extreme lateral thermal gradient. Cooling of the upwelling mantle is here induced by heat transfer to a ca. 50 Ma old plate fronting the ridge-transform intersection. Cooling of the plate edge affects the upper mantle for the whole range where melting usually occurs (30-80 km bsl). The resulting ridge axis consequently shows a lateral gradient in magma productivity and composition (Bonatti et al., 2001 and references therein). MORBs erupted at the ridge centre give rise to a "normal" 5 km thick magmatic crust. Moving to the axial tip magmatism diminishes in volume till zero and progressively increases its alkaline character along with the compositional variability revealing the short-scale heterogeneity of the mantle source (Ligi et al., 2005). This thermal and tectonic configuration represents a regional scale natural experiment where to test the effect of varying mantle potential temperature on a given mantle source. Melting a heterogeneous mantle has profound implications on the km-scale heat transfer because of the differential onset of melting of variably fertile lithologies (Brunelli et al., 2018). Here, we will present the results of the upcoming French-Italian SMARTIES expedition, taking place in July-August 2019. We will present a new high-resolution bathymetric coverage of the RTI and peculiar tectonic features where magma is nearly absent accompanied by direct submarine observations and sampling from Nautile dives.

The United Nations Environment Program defines as waste all the persistent marine debris deposited or abandoned in the sea (marine litter) and beach (beach litter) environment. Thus including all substances or products abandoned or involuntarily dispersed into the sea or on the coastline. It has been estimated that, all around the world, about 10 million tons of waste coming from domestic, commercial and industrial activities reach the seas every year. Moreover, waste floating adrift in the seas and oceans can be carried very far away, reaching different places from the ones they were originated. Further, damage may result to various human activities and equipment, such as navigation, energy production, aquaculture, tourism. In order to identify interventions aimed at reducing the effects of waste inside the sea, an accurate waste characterization both in terms of quantity and quality (composition) is required. The paper reports the results of a study that aimed at characterize the beach litter in the coast of Cadiz, a city in the south-western of Spain. A multivariate cluster analysis was performed to group observed items in dendrograms - obtained on the basis of the frequency on which each type of litter items was found on the beaches in different periods of the year. Results obtained in this study could be adopted as a support to optimize the solid waste collection services and to identify their appropriate fate (recovery and/or disposal). Furthermore, the prevention of waste production, by means of a better organization of the involved activities, can also be obtained.

Il contributo propone una misura di benessere delle regioni italiane in termini di efficienza, considerando simultaneamente dimensioni economiche, sociali ed ambientali. Utilizzando un approccio integrato dell’analisi in componenti principali e dell’Activity Analysis, lo studio fornisce una misura di benessere in termini economici ed ambientali. L’analisi evidenzia una generalizzata incapacità delle regioni italiane di realizzare una buona performance economica ed ambientale. The study proposes a measure of the well-being of Italian regions in terms of efficiency, considering simultaneously economic, social and environmental aspects. The paper suggests an integrated approach using Principal Components Analysis (PCA) and Activity Analysis (AA) to evaluate the equal and sustainable well-being (ESW) of Italian Regions for the years 2005 and 2010. The AA efficiency scores have been used to evaluate in a separate way the sustainable and economic development of regions. The analysis evidences that Italian regions do not show a suitable balance between economic and sustainable performance of well-being.

The aim of the study is to analyse the relationship between recession, population structure and consumption behaviour over the life cycle. To this aim, we consider three clusters of non-durable expenditures such as food at home, work-related and core expenditures. The analysis has been performed on micro data on the Household Budgets for the period 1997-2013. Based on life cycle theory, two statistical models has been estimated, viz. a pre-crisis (1997-2007) and a great recession period (2008-2013) model. The study shows that the recession has entailed a reduction of the average expenditure for each category of consumption, and the intensity of the reduction is different among households and generations.

New multichannel seismic reflection profiles were acquired to unravel the structure of a portion of the eastern margin of the Tyrrhenian basin. This extensional feature is part of an Oligocene to Present back-arc basin in the hangingwall of the west directed Apennines subduction system. The basin provides excellent conditions to investigate the early stage processes leading to the development of rifted passive margins and to the emplacement of oceanic crust in an oblique setting. The interpreted post-stack-migrated seismic profiles highlight the geometry and kinematics of the Pontine escarpment that connects the Latium-Campania continental margin to the Vavilov basin. The latter is the main feature of the area, related to the early Pliocene extension of the Tyrrhenian Sea. Several morphological variations are pointed out along strike, mirroring different structural settings of the margin itself: a steeper margin to the north corresponds to high-angle possibly transtensional faults, whereas a smooth slope in the southern portion corresponds to several more distributed listric faults. This work contributes to the understanding of the interplay between extensional and transtensional tectonics along the margins of an oblique back-arc basin.

SUMMARY We discuss theoretical and computational method on plate-driven mantle flow beneath midocean ridges. We consider a steady-state flow induced by motion of overlying rigid plates in an incompressible viscous mantle beneath a generic ridge-transform-ridge plate boundary. No assumption of orthogonal and symmetric spreading at ridge axis is made. Analytical solutions for viscosity flow in a half-space and in a layered viscosity mantle beneath an infinitesimal thickness lithosphere and beneath plates that thicken with increasing age, are presented. Numerical calculations were carried out using a standard fast Fourier transform algorithm. The difficulty of using standard Fourier methods to predict accurately the mantle flow field in the proximity of the plate boundaries is overcome by applying the Gegenbauer reconstruction post-processing technique to the Fourier pseudo-spectral solutions. Finally, we present some examples of flow computations. We consider, for both models, two different ridge-transformridge geometries consisting of 100 and 1000 km offsets of two ridge segments spreading at 15 mm/yr half rate. We found a significant difference in the flow structure between the two flow models close to ridge axis and ridge-transform intersections. The proposed model and methods are useful for fast mantle flow calculations to investigate melting processes beneath spreading centres, and to predict the relationship between mantle temperature, crustal thickness and geochemistry of the oceanic crust.

New high-resolution bathymetric and magnetic data from the western Aeolian sector, southern Tyrrhenian Sea, provide insights into structural and volcanic development of the area, suggesting a strong interaction between volcanism and tectonics. The analysis of these data combined with relocated earthquake distribution, focal plane solutions and strain rate evaluation indicates that the dextral strike-slip Sisifo-Alicudi shear zone is a complex and wide area of active deformation, representing the superficial expression of the deep seated lithospheric tear fault separating the subduction slab below Sicily and Calabria. Most of the observed volcanic features are aligned along a NW-SE trend, such as the Filicudi island-Alicudi North Seamount and Eolo-Enarete alignments, and are dissected by hundred-metre-high scarps along conjugate NNE-SSW trending fault systems. The magnetic field pattern matches the main trends of volcanic features. Spectral analysis and Euler deconvolution of magnetic anomalies show the existence of both deep and shallow sources. High-amplitude, high-frequency anomalies due to shallow sources are dominant close to the volcanic edifices of Alicudi and Filicudi, while the main contribution on the surrounding Eolo, Enarete, Alicudi North and Filicudi North seamounts is given by low-amplitude anomalies and/or deeper magnetic sources. This is probably related to different ages of the volcanic rocks, although hydrothermal processes may have played an important role in blanketing magnetic anomalies, in particular at Enarete and Eolo seamounts. Relative chronology of the eruptive centres and the inferred deformation pattern outline the Quaternary evolution of the western Aeolian Arc: Sisifo, Alicudi North and Filicudi North seamounts might have developed in an early stage, following the Late Pliocene-Early Pleistocene SE-ward migration of arc-related volcanism due to the Ionian subduction hinge retreat; Eolo, Enarete and Filicudi represent later manifestations that led volcanoes to develop during Mid-Late Pleistocene, when the stress regime in the area changed, due to the SSE-ward propagation of the subduction slab tear fault and the consequent reorientation and decrease of trench migration velocity. Finally, volcanic activity occurred in a very short time span at Alicudi, where an almost conical volcanic edifice emerged, suggesting negligible interactions with regional fault systems.

In this paper, the methodology of fuzzy set is used to analyse the italian Households Budgets of 1992. Two fuzzy-cluster methods are used: the first one, for searching those variables (the budgets expenses) more representative of the households welfare level and more connected with their social and demographics characteristics; the second one, for clustering the original data in some homogeneous groups of consumption behavior, The results can be related to those of other studies that utilize the standard econometric method of analysis: in particular, a welfare index is identified to form five homogeneous groups of households., Statistica; Vol 55, No 4 (1995)

The aim of this paper is to propose a simple novel framework for Economic Statistics. This proposed program is founded on the "core" of the discipline as defined by Zellner: "learning from data and solving practical problems". The program is divided into several arguments referred to the definitions of the macro-aggregates and the interrelations among them, the classification of the economic data and their quality, the use of economic data. For this section it needs referring to real object of Economic Statistics that deals with specific ways of ordering data and testing hypotheses., Statistica; Vol 55, No 1 (1995)

A consumption function at the regional level is proposed and estimated on the basis of data of Sicily in the period 1951-85. The proposed function contains as specific variables both the regional income and the current transfers. An error correction model was used to account for short and long run effects as well as to get estimates in agreeement with the theory. The results are quite encouraging and allow us to draw some interesting conclusions, with respect to the role of current transfers in sustaining both the regional income and the aggregate consumption in the Sicilian economy., Statistica; Vol 50, No 1 (1990)

Rend. Online Soc. Geol. It., Vol. 21 (2012), p. 918. The 'Pietra di Finale' allows to analyse the evolution of Mediterranean during the Chattian to Serravallian interval. The 'Pietra di Finale' deposits unconformably overlies the Alpine substrate. Three main stratigraphic units may be recognized in the sedimentary succession of the Finale area. The first unit is represented by metamorphic and dolostone conglomerates and sandstone that may be interpreted as a fan delta deposits and are Chattian to Aquitanian in age. This deposits pass upward to marls and marly limestone with some sandstone intercalation. This unit, Aquitanian to Burdigalian in age, is known as Torre di Bastia unit and it is overlain with a sharp contact by mixed terrigenouscarbonate deposits. Clasts of terrigenous fraction were mostly derived from the Alpine orogenic wedge, whereas sandstone lithic fragments have a more varied provenance. To reconstruct the paleolatitude position of the Finale succession we made plate kinematic reconstructions of the main blocks in the western and central Mediterranean area, during a time interval t=25 Ma. We explored tectonic evolution in the Eurasia-fixed reference frame, and the hotspot framework, testing both the present-day Atlantic/Indian hotspots and the present--day Pacific hotspots, for the definitions of the reference system. All the cases studied do not provide any significant variation of block positions, resulting in a range of displacements of few degrees of latitude. The carbonate fraction mixed siliciclastic-carbonate unit is dominated by Halimeda. Halimeda is restricted to tropical and subtropical marine environments where they grow either on unconsolidated sediments or on the reef itself. Halimeda green algae tolerate a range of hydrodynamic regimes, flourishing from the back-reef lagoon to the forereef slope, at depths ranging from