1,720,977 research outputs found
Neotettonica dell'area veronese: uno studio integrato fra microrilievo e remote sensing
No full textQuesto lavoro mostra le potenzialità dell'integrazione fra l'interpretazione delle immagini da satellite e del microrilievo per l'individuazione di lineamenti neotettonici in area pedemontana e di pianura. Come area test è stata scelta la porzione di fascia pedemontana veneta compresa fra il Lago di Garda ad ovest e S. Bonifacio a est. L'interpretazione del microrilievo e delle immagini satellitari (Landsat 5 TM) ha messo in evidenza dei sistemi di lineamenti con indizi di attività durante il Quaternario. L'ipotesi di un'unica faglia ai margini meridionali del blocco lessineo (linea di Verona) non sembra confermata dalle analisi effettuate. Si propende piuttosto per un'ampia zona di deformazione costituita da sistemi a diversa orientazione. In particolare è stata dimostrata l'attività recente dei sistemi NNE-SSW (Sistema delBaldo), NNW-SSE (Sistema di Castelvero) e ENE-WSW. Essa legata al basculamento verso sud del blocco lessineo da ricondurre all'effetto del peripheral bulge nell'avampaese della catena appenninica, ad ulteriori raccorciamenti crostali in atto o al roll-back della litosfera Adria in subduzione sotto la catena appenninica stessa
Relationships between biosphere and cryosphere in a climate change frame at Ny-Alesund – CCT
No full textGeomechanical characterisation of Liro and Livo lithologies (northern Lake Como, Italy): the first report
No full textThe geomechanical characterisation of rock masses is an important step in any geological hazard study. In Liro and Livo catchment basins (northern Lake Como, Italy) rock masses are made up of different materials, frequently tectonically disturbed. In fact, the structural setting of the basins is strongly influenced by the presence of the E-W Tonale fault and by its related lineaments that cross the area. In Liro (56 km2) and Livo (47 km2) basins a large number of rock slope instability phenomena and debris flows are present, often involving sheared rock masses. In order to derive more information with respect to the in situ scale rock mass properties and their variance across the shear zones, the Geological
Strength Index (GSI) was estimated on 51 outcrops of limestone, gneiss, granodiorite and schists, and successively, the Hoek-Brown strength parameters were derived. On the same stations a a structural survey (slikenside lineations) was also carried out. Since tectonically disturbed rockmass are the sources of material for
debris flow, rockfalls and rockslides in the study areas, the first approach utilised was a geomechanical characterization of the lithology and a preliminary assessment of its relationship with the main structural feature. In fact, studies examining the eomechanical
properties of such heavily fractured shear zones and fault zones and relating these properties to the local structural setting are rare: in this context it is important to characterize the lithologies to predict their behaviour. Geomechanical data allow to say that the GSI values are not directly influenced by the Tonale fault but only by
its secondary lineaments, that have a direct action in the shape of the basin hydrographic pattern and in the location and evelopment of debris flows
Stability Analysis of a Landslide Scarp by Means of Virtual Outcrops: The Mt. Peron Niche Area (Masiere di Vedana Rock Avalanche, Eastern Southern Alps)
Full text linkWe investigated the Mt. Peron niche area of the Masiere di Vedana rock avalanche (BL), one of the major mass movements that affected the Eastern Southern Alps in historical times. So far, a geomechanical characterization and a stability analysis of the niche area, where potential rockfall sources are present, are lacking. The Mt. Peron niche area is a rocky cliff almost inaccessible to field-based measurements. In order to overcome this issue, we performed a geo-structural characterization of a sector of the cliff by means of a UAV-based photogrammetric survey. From the virtual outcrop, we extracted the orientation of 159 fractures that were divided into sets based on a K-means clustering algorithm and field-checked with some measurements collected along a rappelling descent route down to the cliff. Finally, with the aim of evaluating the stability of the volume under investigation, we performed a stability analysis of three rock pillars included in our survey by means of a distinct element numerical simulation. Our results indicate that two out of the three pillars are characterized by a stable state, under the simulation assumptions, whereas the third is close to failure, and for this reason, its condition needs further investigation
Stability Analysis of a Landslide Scarp by Means of Virtual Outcrops: The Mt. Peron Niche Area (Masiere di Vedana Rock Avalanche, Eastern Southern Alps)
Full text linkWe investigated the Mt. Peron niche area of the Masiere di Vedana rock avalanche (BL), one of the major mass movements that affected the Eastern Southern Alps in historical times. So far, a geomechanical characterization and a stability analysis of the niche area, where potential rockfall sources are present, are lacking. The Mt. Peron niche area is a rocky cliff almost inaccessible to field-based measurements. In order to overcome this issue, we performed a geo-structural characterization of a sector of the cliff by means of a UAV-based photogrammetric survey. From the virtual outcrop, we extracted the orientation of 159 fractures that were divided into sets based on a K-means clustering algorithm and field-checked with some measurements collected along a rappelling descent route down to the cliff. Finally, with the aim of evaluating the stability of the volume under investigation, we performed a stability analysis of three rock pillars included in our survey by means of a distinct element numerical simulation. Our results indicate that two out of the three pillars are characterized by a stable state, under the simulation assumptions, whereas the third is close to failure, and for this reason, its condition needs further investigation
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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