Il presente lavoro analizza lo stato delle conoscienze relative all'evoluzione geologica (str... more Il presente lavoro analizza lo stato delle conoscienze relative all'evoluzione geologica (stratigrafica e tettonica) quaternaria dell'area colpita dal terremoto del 6 Aprile 2009 al momento dell'occorrenza dell'evento sismico. Published 24-29 3.2. Tettonica attiva N/A or not JCR
We present a collection of pictures of the coseismic secondary geological effects produced on the... more We present a collection of pictures of the coseismic secondary geological effects produced on the environment by the 2012 Emilia seismic sequence in northern Italy. The May-June 2012 sequence struck a broad area located in the Po Plain region, causing 26 deaths and hundreds of injured, 15.000 homeless, severe damage of historical centres and industrial areas, and an estimated economic toll of ~2 billion of euros. The sequence included two mainshocks (Figure 1): the first one, with ML 5.9, occurred on May 20 between Finale Emilia, S. Felice sul Panaro and S. Martino Spino; the second one, with ML 5.8, occurred 12 km southwest of the previous mainshock on May 29. Both the mainshocks occurred on about E-W trending, S dipping blind thrust faults; the whole aftershocks area extends in an E-W direction for more than 50 km and includes five ML≥5.0 events and more than 1800 ML>1.5 events. Ground cracks and liquefactions were certainly the most relevant coseismic geological effects observ...
An almost complete salamandrid specimen has recently been discovered from diatomite deposits in t... more An almost complete salamandrid specimen has recently been discovered from diatomite deposits in the Sabatini Volcanic District, at the Fosso di San Martino locality, about 45 km north of Rome (Rignano Flamino, Latium, central Italy). The age of the fossilbearing level is constrained between 488±2 and 457±4 ka based on the presence of well-dated volcanic ash layers at the top and at the bed of the diatomite level where the specimen was embedded. The fossil record of Caudata from the Pleistocene of central Italy is scarce, and this new find adds important data on the presence of the taxon in this area. The specimen, although comprised of a fairly complete and articulated skeleton, shows a sub-optimal preservation of single bony elements, to such an extent that a definite taxonomic assignment is not feasible. Moreover, it probably represents a juvenile individual in somatic terms at the time of the death. The specimen is tentatively referred to Triturus sp. RIASSUNTO-[Un salamandride dal Pleistocene medio del Lazio settentrionale (Fosso di San Martino, Roma, Italia)]-Un esemplare quasi completo di Salamandridae è stato recentemente scoperto nei depositi diatomitici del Distretto Vulcanico Sabatino, presso la località Fosso di San Martino, circa 45 km a nord di Roma (Rignano Flaminio, Lazio, Italia centrale). La presenza di livelli vulcanici al tetto e al letto del livello diatomitico da cui proviene il nuovo esemplare, già datati con metodo 40 Ar/ 39 Ar in precedenti lavori, ha permesso di restringere l'intervallo temporale tra i 488±2 e i 457±4 mila anni fa. Il registro fossile pleistocenico relativo ai Caudata è scarso per l'Italia centrale ed in generale per tutto il territorio italiano. Il ritrovamento di un nuovo esemplare aggiunge quindi dati utili circa la distribuzione degli anfibi in questa area geografica. L'esemplare, benché sufficientemente completo, presenta tuttavia uno stato di conservazione sub-ottimale, in quanto in gran parte preservato come sottile pellicola organica o come modello esterno dello scheletro originale. Il particolare stato di conservazione ha limitato le possibilità di una attribuzione tassonomica a livello di specie. Inoltre, l'esemplare potrebbe non aver raggiunto la maturità somatica al momento della morte. In base ai dati morfometrici derivati dall'analisi dell'esemplare, quest'ultimo è provvisoriamente attribuito al genere Triturus.
Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been... more Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been made in order to develop a procedure for the paleoseismological analysis of bedrock fault scarps. The CF fault has been responsible for the formation of an impressive limestone fault scarp. Geomorphologic work on the CF basin and related fault indicated that the scarp originated from tectonic fault displacements. Three morphologic units have been distinguished along the fault scarp and defined as morphosome M1 (lowest part of the scarp), M2 and M3 (the uppermost part). These units display different karstic features, which are the result of their different duration of exposure to weathering. Micromorphologic analyses focused on the morphosome M1, along which the CF fault plane is exposed for a height ranging between 4 and 7 m. These analyses were aimed at defining differently weathered bands located at various heights, and parallel to the fault scarp top and base. The presence of these bands suggests repeated fault movements. The exposed fault surface displays a low-grade biokarstic weathering due to the action of epilithic and endolithic organisms. The biokarst distribution is, however, inhomogeneous and conditioned by the presence of nourishing elements, moisture and by light intensity. An area preferentially affected by the biokarstic processes develops as a band at the bedrock-soil contact at the base of the scarp. Roughness and colour analyses were made to identify uplifted bands which previously formed at the bedrock-soil contact. The roughness analysis was made using a microroughness-meter along 20-cm long horizontal transects repeated each 20 cm of fault height for the entire morphosome M1, at various sites along the scarp. The roughness variance data, plotted vs. the fault height, failed to identify differently weathered bands of paleoseismological interest. This result is probably due to the complex distribution of biokarst along the investigated fault plane. More reliable results have been obtained by areal analysis of the variation of the colour rendering of the rocks exposed along the fault plane at different sites. Photographic images of large portions of fault surfaces have been processed with standard graphic computer programs. The variations of colour indicated the presence of bands at various heights along the fault plane. Two uplifted bands have been recognised at all the investigated sites suggesting two displacement events (E1 and E2). A preliminary chronological framework for these two events, the youngest of which affected
The time span necessary to define a fault as 'active and capable' can mainly be derived from the ... more The time span necessary to define a fault as 'active and capable' can mainly be derived from the framework of the regulations and the literature produced since the 1970s on risk estimation in engineering planning of strategic buildings. Within this framework, two different lines of thought can be determined, which have mainly developed in the USA. On the one side, there is a tendency to produce 'narrow' chronological definitions. This is particularly evident in the regulatory acts for the planning of nuclear reactors. The much more effective second line of thought anchors the chronological definitions of the terms active' and, therefore 'capable', to the concept of 'seismotectonic domain'. As these domains are different in different regions of the World, the chronological definition cannot be univocal; i.e., different criteria are needed to define fault activity, which will depend on the characteristics of the local tectonic domain and of the related recurrence times of fault activation. Current research on active tectonics indicates that methodological aspects can also condition the chronological choice to define fault activity. Indeed, this practice implies the use of earth science methods, the applications of which can be inherently limited. For example, limits and constraints might be related to the availability of datable sediments and landforms that can be used to define the recent fault kinematic history. For the Italian territory, we consider two main tectonic domains: (a) the compressive domain along the southern margin of the Alpine chain and the northern and northeastern margins of the Apennines, which is characterised by the activity of blind thrusts and reverse faults; and (b) the extensional domain of the Apennines and the Calabria region, which is often manifest through the activity of seismogenic normal and normaloblique faults. In case (a), the general geomorphic and subsurficial evidence of recent activity suggests that a reverse blind fault or a blind thrust should be considered active and potentially capable if showing evidence of activity during the Quaternary (i.e., over the last 2.6 Myr), unless information is available that documents its inactivity since at least the Last Glacial Maximum (LGM) (ca. 20 ka). The choice of the LGM period as the minimum age necessary to define fault
GNGTS (Gruppo Nazionale di Geofisica della Terra Solida) abstract session, 2007
A first detailed investigation of Pantelleria submarine portions was carried out in November 2006... more A first detailed investigation of Pantelleria submarine portions was carried out in November 2006 (aboard R\ V Urania) using a 50 kHz multibeam bathymetry system and collecting seafloor samples by dredging, grabbing, coring. The high resolution bathymetric data, acquired from–50 m down to-1200 m, furnished a digital terrain model with a grid-size of 5 m in shallow water and 10 m in deep water, allowing a detailed morphological reconstruction of the seafloor geological features (Fig. 1).
1). L'analisi sull'evoluzione temporale dello sviluppo della rete, ottenuta confrontando le fines... more 1). L'analisi sull'evoluzione temporale dello sviluppo della rete, ottenuta confrontando le finestre relative a due intervalli temporali strumentalmente omogenei (1995-1999; 2000-2007), ha evidenziato un netto miglioramento delle capacità di rilevazione della rete nel tempo, con un evidente abbassamento del valore di Mp.
Il presente lavoro analizza lo stato delle conoscienze relative all'evoluzione geologica (str... more Il presente lavoro analizza lo stato delle conoscienze relative all'evoluzione geologica (stratigrafica e tettonica) quaternaria dell'area colpita dal terremoto del 6 Aprile 2009 al momento dell'occorrenza dell'evento sismico. Published 24-29 3.2. Tettonica attiva N/A or not JCR
We present a collection of pictures of the coseismic secondary geological effects produced on the... more We present a collection of pictures of the coseismic secondary geological effects produced on the environment by the 2012 Emilia seismic sequence in northern Italy. The May-June 2012 sequence struck a broad area located in the Po Plain region, causing 26 deaths and hundreds of injured, 15.000 homeless, severe damage of historical centres and industrial areas, and an estimated economic toll of ~2 billion of euros. The sequence included two mainshocks (Figure 1): the first one, with ML 5.9, occurred on May 20 between Finale Emilia, S. Felice sul Panaro and S. Martino Spino; the second one, with ML 5.8, occurred 12 km southwest of the previous mainshock on May 29. Both the mainshocks occurred on about E-W trending, S dipping blind thrust faults; the whole aftershocks area extends in an E-W direction for more than 50 km and includes five ML≥5.0 events and more than 1800 ML>1.5 events. Ground cracks and liquefactions were certainly the most relevant coseismic geological effects observ...
An almost complete salamandrid specimen has recently been discovered from diatomite deposits in t... more An almost complete salamandrid specimen has recently been discovered from diatomite deposits in the Sabatini Volcanic District, at the Fosso di San Martino locality, about 45 km north of Rome (Rignano Flamino, Latium, central Italy). The age of the fossilbearing level is constrained between 488±2 and 457±4 ka based on the presence of well-dated volcanic ash layers at the top and at the bed of the diatomite level where the specimen was embedded. The fossil record of Caudata from the Pleistocene of central Italy is scarce, and this new find adds important data on the presence of the taxon in this area. The specimen, although comprised of a fairly complete and articulated skeleton, shows a sub-optimal preservation of single bony elements, to such an extent that a definite taxonomic assignment is not feasible. Moreover, it probably represents a juvenile individual in somatic terms at the time of the death. The specimen is tentatively referred to Triturus sp. RIASSUNTO-[Un salamandride dal Pleistocene medio del Lazio settentrionale (Fosso di San Martino, Roma, Italia)]-Un esemplare quasi completo di Salamandridae è stato recentemente scoperto nei depositi diatomitici del Distretto Vulcanico Sabatino, presso la località Fosso di San Martino, circa 45 km a nord di Roma (Rignano Flaminio, Lazio, Italia centrale). La presenza di livelli vulcanici al tetto e al letto del livello diatomitico da cui proviene il nuovo esemplare, già datati con metodo 40 Ar/ 39 Ar in precedenti lavori, ha permesso di restringere l'intervallo temporale tra i 488±2 e i 457±4 mila anni fa. Il registro fossile pleistocenico relativo ai Caudata è scarso per l'Italia centrale ed in generale per tutto il territorio italiano. Il ritrovamento di un nuovo esemplare aggiunge quindi dati utili circa la distribuzione degli anfibi in questa area geografica. L'esemplare, benché sufficientemente completo, presenta tuttavia uno stato di conservazione sub-ottimale, in quanto in gran parte preservato come sottile pellicola organica o come modello esterno dello scheletro originale. Il particolare stato di conservazione ha limitato le possibilità di una attribuzione tassonomica a livello di specie. Inoltre, l'esemplare potrebbe non aver raggiunto la maturità somatica al momento della morte. In base ai dati morfometrici derivati dall'analisi dell'esemplare, quest'ultimo è provvisoriamente attribuito al genere Triturus.
Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been... more Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been made in order to develop a procedure for the paleoseismological analysis of bedrock fault scarps. The CF fault has been responsible for the formation of an impressive limestone fault scarp. Geomorphologic work on the CF basin and related fault indicated that the scarp originated from tectonic fault displacements. Three morphologic units have been distinguished along the fault scarp and defined as morphosome M1 (lowest part of the scarp), M2 and M3 (the uppermost part). These units display different karstic features, which are the result of their different duration of exposure to weathering. Micromorphologic analyses focused on the morphosome M1, along which the CF fault plane is exposed for a height ranging between 4 and 7 m. These analyses were aimed at defining differently weathered bands located at various heights, and parallel to the fault scarp top and base. The presence of these bands suggests repeated fault movements. The exposed fault surface displays a low-grade biokarstic weathering due to the action of epilithic and endolithic organisms. The biokarst distribution is, however, inhomogeneous and conditioned by the presence of nourishing elements, moisture and by light intensity. An area preferentially affected by the biokarstic processes develops as a band at the bedrock-soil contact at the base of the scarp. Roughness and colour analyses were made to identify uplifted bands which previously formed at the bedrock-soil contact. The roughness analysis was made using a microroughness-meter along 20-cm long horizontal transects repeated each 20 cm of fault height for the entire morphosome M1, at various sites along the scarp. The roughness variance data, plotted vs. the fault height, failed to identify differently weathered bands of paleoseismological interest. This result is probably due to the complex distribution of biokarst along the investigated fault plane. More reliable results have been obtained by areal analysis of the variation of the colour rendering of the rocks exposed along the fault plane at different sites. Photographic images of large portions of fault surfaces have been processed with standard graphic computer programs. The variations of colour indicated the presence of bands at various heights along the fault plane. Two uplifted bands have been recognised at all the investigated sites suggesting two displacement events (E1 and E2). A preliminary chronological framework for these two events, the youngest of which affected
The time span necessary to define a fault as 'active and capable' can mainly be derived from the ... more The time span necessary to define a fault as 'active and capable' can mainly be derived from the framework of the regulations and the literature produced since the 1970s on risk estimation in engineering planning of strategic buildings. Within this framework, two different lines of thought can be determined, which have mainly developed in the USA. On the one side, there is a tendency to produce 'narrow' chronological definitions. This is particularly evident in the regulatory acts for the planning of nuclear reactors. The much more effective second line of thought anchors the chronological definitions of the terms active' and, therefore 'capable', to the concept of 'seismotectonic domain'. As these domains are different in different regions of the World, the chronological definition cannot be univocal; i.e., different criteria are needed to define fault activity, which will depend on the characteristics of the local tectonic domain and of the related recurrence times of fault activation. Current research on active tectonics indicates that methodological aspects can also condition the chronological choice to define fault activity. Indeed, this practice implies the use of earth science methods, the applications of which can be inherently limited. For example, limits and constraints might be related to the availability of datable sediments and landforms that can be used to define the recent fault kinematic history. For the Italian territory, we consider two main tectonic domains: (a) the compressive domain along the southern margin of the Alpine chain and the northern and northeastern margins of the Apennines, which is characterised by the activity of blind thrusts and reverse faults; and (b) the extensional domain of the Apennines and the Calabria region, which is often manifest through the activity of seismogenic normal and normaloblique faults. In case (a), the general geomorphic and subsurficial evidence of recent activity suggests that a reverse blind fault or a blind thrust should be considered active and potentially capable if showing evidence of activity during the Quaternary (i.e., over the last 2.6 Myr), unless information is available that documents its inactivity since at least the Last Glacial Maximum (LGM) (ca. 20 ka). The choice of the LGM period as the minimum age necessary to define fault
GNGTS (Gruppo Nazionale di Geofisica della Terra Solida) abstract session, 2007
A first detailed investigation of Pantelleria submarine portions was carried out in November 2006... more A first detailed investigation of Pantelleria submarine portions was carried out in November 2006 (aboard R\ V Urania) using a 50 kHz multibeam bathymetry system and collecting seafloor samples by dredging, grabbing, coring. The high resolution bathymetric data, acquired from–50 m down to-1200 m, furnished a digital terrain model with a grid-size of 5 m in shallow water and 10 m in deep water, allowing a detailed morphological reconstruction of the seafloor geological features (Fig. 1).
1). L'analisi sull'evoluzione temporale dello sviluppo della rete, ottenuta confrontando le fines... more 1). L'analisi sull'evoluzione temporale dello sviluppo della rete, ottenuta confrontando le finestre relative a due intervalli temporali strumentalmente omogenei (1995-1999; 2000-2007), ha evidenziato un netto miglioramento delle capacità di rilevazione della rete nel tempo, con un evidente abbassamento del valore di Mp.
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