1,721,024 research outputs found
Extensional regime in the northern Apennines: Indications from the lithospheric behaviour
No full textThe aim of this work is to assess the conditions leading to extension during the tectonic evolution of the Northern Apennine chain, starting from the reconstruction of the rheological behaviour of the lithosphere underneath the chain. The temperature field and the strength of the lithosphere during the evolution of the belt in different sectors of the Northern Apennines, are calculated. A model, which assumes that the heat is transported by conduction and advection, is used to mimic a thermal perturbation migrating from west to east. The thermal regime is influenced by simultaneous crustal thickening in the easternmost sector and by advection due to extensional processes in the western sector of the chain. Rheological profiles and the strength of the lithosphere for different sectors of the chain at different times are obtained and compared with the difference in potential energy connected to the stress induced by compensated topography. The results show that, for homogeneous crustal thickening, the advection term moving form west to east would increase the tensile deviatoric stress in the area where the transition between the advection and thickening processes is located: in this area the strength is reduced in such a way as to trigger extension. © 2006 - OGS
High resolution DEM from stereopairs: examples from Nili Fossae and Gale crater, Mars
Full text linkIn this work, we present two Digital Elevation Models (DEM) obtained from stereopairs produced by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter (MRO). Target regions are chosen among the most intriguing and studied of Mars and are the western trench of the Nili Fossae and the northern portion of the central peak of the Gale crater. The terrains found in the first have proven to have a significant compositional variability whose spatial distribution is related to their morphology. The canyon found in the Gale crater is important to extend the comprehension of those geologic processes observed by the Curiosity rover, up to a distance and a morphologic context (the wall of the canyon) unreachable by the rover. The high resolution of the HiRISE images (0.25 m/pixel) from which we started allowed us to
produce the DEM with higher resolution and increased detail respect to the topographic model derived from the Mars Orbiter Laser Altimeter (MOLA) data
Le Marche: varietà di paesaggi, percezioni e geomorfologia.
No full textGli autori, dopo alcune riflessioni epistemiche sull’oggetto della geografia, con questo contributo intendono intrecciare e chiarire il dialogo tra natura e società che ha generato nella regione Marche varietà paesaggistiche numerose e diverse, seppure complementari. Tali da costituire un patrimonio, non ancora adeguatamente valorizzato per l’immagine regionale, che nasce dalla storia naturale e da quella sociale. Su tale prospettiva si vuole sollecitare l’attenzione degli studiosi sull’approccio al paesaggio, nella sua materialità e immaterialità, in chiave ambientale e culturale, quali aspetti diversi ma intimamente embricati e inscindibili del sistema paesaggistico
Turismo, dimore rurali e paesaggio geomorfologico della Sardegna: le regioni degli stazzi e delle corti campidanesi a confronto
No full textLa Sardegna presenta da sempre una forte vocazione turistica, specialmente nelle aree costiere. Il turismo balneare in Sardegna rappresenta un’ importante attività economica nella sua duplice veste di fenomeno sia di massa, sia elitario. Il successo di questo turismo, ormai consolidato, risiede principalmente nelle eccezionalità e spettacolarità dei paesaggi costieri, che rispecchiano la grande varietà litologica e geomorfologica dell’Isola. Al contrario le regioni interne, anche se estremamente interessanti e, a volte, anche più singolari, non hanno lo stesso richiamo turistico e sembrano non poter competere con le tradizionali zone turistiche isolane. La nuova domanda, alla ricerca di una fruizione dei paesaggi che sia alternativa a quella esclusivamente balneare e arricchita di contenuti culturali, oltre che diversamente distribuita nel corso dell’anno, ha stimolato anche l’offerta degli spazi interni e rurali dell’Isola, rimasti per troppo tempo lontano dalle attenzioni dei visitatori. Gli esempi di questo coinvolgimento hanno portato alcune regioni della Sardegna, come la Gallura e il Campidano, a riproporre i propri paesaggi rurali valorizzando in modo particolare il loro patrimonio architettonico e culturale, dove le dimore tradizionali, legate all’agricoltura e alla pastorizia, come stazzi e corti campidanesi ritrovano il loro antico splendore per essere fruiti dal turismo. Si vuole qui proporre, da una parte l’analisi dei caratteri storico-geografici dell’insediamento rurale delle due su citate regioni e il loro contesto geomorfologico, dall’altra la verifica di come la ricchezza geografica e culturale dei paesaggi interni possa stimolare nuove occasioni di fruizione turistica e di sviluppo per le comunità locali.Sardinia is mainly known for its high tourist vocation, particularly, in its coastal sector. The success of its consolidated tourist call lies firstly in the peculiarity and spectacularity of its coastal landscape.
Nevertheless, the inland areas and landscapes, even if extremely interesting from a scientific point of view and sometimes even more spectacular, cannot yet be considered as a real tourist call and cannot compete to the main tourist flux, traditionally located along the coast.
The aim of a tourist fruition of the region alternative to the traditional one and the research of a cultural enrichment, stimulated the tourist offer also of the inland and rural landscapes of the island.
Some examples of this trend are carried out in some Sardinian areas like Gallura (north-eastern Sardinia) and Campidano (south-western Sardinia): here projects of improvement of rural and inland landscapes are proposed, mainly through the offer and improvement of the rich cultural and architectonic heritage, highly represented by the traditional rural homes, like the stazzi and corti, brought back to their original beauty.
With this work we want to describe the great richness of these two areas, both from a geographical and geomorphological point of view and from the historical characters of the rural culture and settlement. The great geographical and cultural heritage of inland areas can be an important chance in tourist fruition and for new planning and management strategies directly involving local communities
La stratificazione culturale del sito del Castello Aragonese di Taranto nella ricostruzione del paesaggio
No full text3D GPR imaging for paleoseismology in Central Appennines (Italy)
No full textThe knowledge of spatial position and geologic characteristics of active faults is fundamental to locate these elements on geologic maps and better define the potential seismological hazard of an area. A Quaternary fault in the “Piano di Castelluccio” basin, in Central Italy, has been already studied through paleoseismological analysis, provided stratigraphic data on sedimentary units and highlighted evidences of “recent” faulting related to past strong earthquakes. This fault has been defined “silent”, because events were not included in the current seismic catalogues, retaining uncertainties in the definition of the seismic hazard of that area. 2D/3D GPR surveys were done to image the fault zone and to provide new complementary data on the shallow sediments. The 3D data provides continuity of information over the investigation site, characterizing the structure in a total non-invasive way, whilst long 2D profiles were used to extend the study on a wider area. Final images show a characteristic GPR signature of a tectonic structure and faulted units: data reveal its position and continuity in space and highlight clear geometric features, providing useful qualitative and quantitative complementary data. Keywords - 2D/3D GPR, normal faults, paleoseismology, attributes analysis
2D and 3D Ground Penetrating Radar (GPR) can improve paleoseismological researches: an example from the Mt. Vettore Fault (Central Appennines, Italy)
No full textThe ScanMars experiment in Amadee18 Mars simulation: GPR images of subsurface geologic structures from the Dhofar desert (Sultanate of Oman)
No full textThe characterization of buried geologic structures can be considered one of the most important goals of the
planetary subsurface exploration. Such valuable information can be provided by the geophysical techniques not
only on the Earth, but even on planets like Mars. Ground-penetrating radar (GPR) is a geophysical method
widely used in many applications. Future landing vehicles like EXOMARS - 2020 NASA ROVER will also bring
a GPR aiming to obtain high-resolution subsurface images. Recently, “AMADEE18 Mars Analogue Simulation”
has included the “ScanMars” experiment, during which analogue astronauts collected 24 GPR profiles across
the study site in the Dhofar Region (Sultanate of Oman). About 1400 meters of profiles, a total of 70’000 radar
echoes were recorded in four sites with different geological characteristics. The processed data show a good
quality and a max penetration depth of about 5 meters. “ScanMars” data display dipping horizons, strong
reflections, sectors with differential signal strength/attenuation and reflectors geometries showing features
typical of dried Wadi riverbed environments. Our experiment confirms the GPR is a valuable tool for planetary
exploration, allowing to extend in depth the surface observation and pursuing the main objective of studying
water-related subsurface geologic features
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