This work identifies the branch point, which was never explicit in EM treatises, from which came the choice of abandoning the Galilean transformations in favor of the Lorentz covariance, a path that originated the var...This work identifies the branch point, which was never explicit in EM treatises, from which came the choice of abandoning the Galilean transformations in favor of the Lorentz covariance, a path that originated the various relativistic theories. The need arising from the expanding Earth for a hydrodynamic mechanism for Newtonian and Coulomb fields is discussed. This hydrodynamic material mechanism is shown to constitute a completion of the Newton and Maxwell concepts of the fields, which were only a phenomenological description of physical reality. It is shown that the analogy between Maxwell’s equations and hydrodynamics cannot become a perfect correspondence. The lack of coupling of the electromagnetic field to the underlying material “causing field”—which induces hydrodynamical forces and accelerations observed only phenomenologically—gives rise to inaccuracies in the formulation of its equations, which are incorrect for Galilean covariance. But the most serious flaw in the original formulation of electromagnetism is the erroneous identification of the flow velocity of the field (variable as 1/r2) with the speed of light c, with which it was demonstrated that the fields of charges in motion contract in the direction of motion (the Heaviside ellipsoid, 1888, 1889). From this error, historically due to the incomplete development of many hydrodynamics sectors (a situation that persists today), came Fitz Gerald’s contractions and finally, the relativistic theories. Some future research lines are proposed for a return to realistic physics and a possible but still weak form of Galilean covariance.展开更多
Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work...Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work, we present a comprehensive investigation of the performances of two antennas(the u-blox ANN-MB and the TOPGNSS TOP-106) used on a low-cost GNSS receiver known as the u-blox ZED-F9P. The two antennas were installed on two identical and co-located u-blox receivers. Data used from both receivers cover the period from January to June 2022. Results from the study indicate that the signal strengths are dominantly greater for the receiver with the TOPGNSS antenna than for the receiver with the ANN-MB antenna, implying that the TOPGNSS antenna is better than the ANN-MB antenna in terms of providing greater signal strengths. Summarily, the TOPGNSS antenna also performed better in minimizing the occurrence of cycle slips on phase TEC measurements. There are no conspicuous differences between the variances(computed as 5-min standard deviations) of phase TEC measurements for the two antennas, except for a period around May-June when the TOPGNSS gave a better performance in terms of minimizing the variances in phase TEC. Remarkably, the ANN-MB antenna gave a better performance than the TOPGNSS antenna in terms of minimizing the variances in pseudorange TEC for some satellite observations. For precise horizontal(North and East) positioning, the receiver with the TOPGNSS antenna gave better results, while the receiver with the ANN-MB antenna gave better vertical(Up) positioning. The errors for the receivers of both antennas are typically within about 5 m(the monthly mean was usually smaller than 1 m) in the horizontal direction and within about 10 m(the monthly mean was usually smaller than 4 m) in the vertical direction.展开更多
During ancient times,human interest in naturally-occurring gases was religious,while it was scientific in the historical age and industrial in modern times.Gases were also utilized for practical purposes and more than...During ancient times,human interest in naturally-occurring gases was religious,while it was scientific in the historical age and industrial in modern times.Gases were also utilized for practical purposes and more than 3000 years before present day,Chinese populations made use of methane for salt extraction while in the 17th century it was observed that native Americans ignited methane seepages.The development of human thinking on gases followed the fundamental steps that characterized the natural sciences during the 18th century scientific revolution that was based on significant improvements in analytical methods.These improvements are still ongoing while present-day scientific publications evidence the spread of the field of interest and more cooperation with geophysical sciences to solve common interest problems.The existence of proper meetings and dedicated scientific journals confirms that gas geochemistry has ended this pioneering phase to enter a more mature condition.展开更多
In this work,an approach is developed to study the seismicity associated with the impoundment and level changes of a water reservoir(reservoir induced seismicity e RIS).The proposed methodology features a combination ...In this work,an approach is developed to study the seismicity associated with the impoundment and level changes of a water reservoir(reservoir induced seismicity e RIS).The proposed methodology features a combination of a semi-analytical poroelastic model with an earthquake nucleation approach based on rate-and-state frictional law.The combined approach was applied to the case of the Pertusillo Lake,located in the Val d’Agri area(Italy),whose large seasonal water level changes are believed to induce protracted micro-seismicity(local magnitude ML<3).Results show that the lake impoundment in 1962 could have produced up to 0.5 bar(1 bar=100 kPa)changes in Coulomb failure stress(DCFS),while the seasonal water level variation is responsible for variation up to 0.05 bar.Modeling results of the seismicity rates in 20012014 show that the observed earthquakes are well correlated with the modeled DCFS.Finally,the reason that the seismicity is only observed at southwest of the Pertusillo Lake is provided,which is likely attributed to different rock lithologies and depletion caused by significant hydrocarbon exploitation in the northeastern sector of the lake.展开更多
Earthquake is a sudden release of energy due to fault motions.The severity of the damages can be minimized by development of a culture of prevention which includes the Seismic Hazard Assessment,microzonation studies a...Earthquake is a sudden release of energy due to fault motions.The severity of the damages can be minimized by development of a culture of prevention which includes the Seismic Hazard Assessment,microzonation studies and appropriate building codes.展开更多
Machine learning is becoming increasingly important in scientific and technological progress,due to its ability to create models that describe complex data and generalize well.The wealth of publicly-available seismic ...Machine learning is becoming increasingly important in scientific and technological progress,due to its ability to create models that describe complex data and generalize well.The wealth of publicly-available seismic data nowadays requires automated,fast,and reliable tools to carry out a multitude of tasks,such as the detection of small,local earthquakes in areas characterized by sparsity of receivers.A similar application of machine learning,however,should be built on a large amount of labeled seismograms,which is neither immediate to obtain nor to compile.In this study we present a large dataset of seismograms recorded along the vertical,north,and east components of 1487 broad-band or very broad-band receivers distributed worldwide;this includes 629,0953-component seismograms generated by 304,878 local earthquakes and labeled as EQ,and 615,847 ones labeled as noise(AN).Application of machine learning to this dataset shows that a simple Convolutional Neural Network of 67,939 parameters allows discriminating between earthquakes and noise single-station recordings,even if applied in regions not represented in the training set.Achieving an accuracy of 96.7,95.3,and 93.2% on training,validation,and test set,respectively,we prove that the large variety of geological and tectonic settings covered by our data supports the generalization capabilities of the algorithm,and makes it applicable to real-time detection of local events.We make the database publicly available,intending to provide the seismological and broader scientific community with a benchmark for time-series to be used as a testing ground in signal processing.展开更多
Earth Science observations and the Borexino and KamLAND geoneutrino experiments provide clues on the role of aether in the evolution of the Earth, planets, and all other universal structures. Analysis of the problem o...Earth Science observations and the Borexino and KamLAND geoneutrino experiments provide clues on the role of aether in the evolution of the Earth, planets, and all other universal structures. Analysis of the problem of storage of aether entering celestial bodies led to a hydrodynamic explanation of gravitation which in turn was found to be closely related to the expanding Earth and to several other phenomena. Variable radius paleogeography provides an approximate assessment of the quantity of ordinary matter added to the planet per time unit, and some inferences about the Earth’s inner energy balance. The aether density, flow rate, and velocity are computed with the help of astrophysics. The origins of cosmological and gravitational redshift are unified under the single cause of gravitation. This is linked to the similar but not interchangeable concept of tired light, which was considered very plausible by cosmologists like Edwin Hubble and Fritz Zwicky. A superluminal speed was calculated for aether at the Earth’s surface. INFN experiments confirm hydrodynamic gravitation and superluminal velocities, and it is possible to identify interrelations of aether parameters with the currently known cosmological parameters H<sub>0</sub>, G, and c. Unification of hydrodynamic gravitation and the expansion of the celestial bodies through the existence of a minor dissipative force, a non-Newtonian concept, involves a revision of the theories of physics and cosmology, in which the currently accepted laws of physics will be only considered good approximations of a more complex reality.展开更多
Seismic data of earthquakes recorded during the last 40 years in southern Calabria have been compared with geological data in order to obtain a seismotectonic picture of the area. We sought for any possible correlatio...Seismic data of earthquakes recorded during the last 40 years in southern Calabria have been compared with geological data in order to obtain a seismotectonic picture of the area. We sought for any possible correlation between the main regional tectonic structures, the distribution of earthquake hypocentres and the focal mechanism of earthquakes with magnitude(Ml)≥3.Studies of historical and recent seismicity and analysis of geological structures allowed to define the main shear strips on a regional scale. More than 2600 earthquakes with 1.5 ≤ Ml ≤ 4.5 have been considered. The focal mechanisms of earthquakes with Ml≥3 have been compared with the kinematics of known faults and used to give insight on the current active stress field. From the analysis carried out it was possible to expand the cognitive framework regarding the activity of the main tectonic structures present in the area. This study also served to identify areas of high seismicity which do not correspond to any evidence of tectonic structures on the surface, and areas where recognized tectonic structures have not shown any seismicity during the last decades. These cases could be the subject of future investigation in order to correctly assess the seismic hazard in Calabria.This task is important in the context of seismic hazard evaluation and mitigation.展开更多
The tectonics and geodynamics of the Calabria region are presented in this study. These are inferred by precise computation of Global Navigation Satellite Systems （GNSS） per~ manent station velocities in a stable Eu...The tectonics and geodynamics of the Calabria region are presented in this study. These are inferred by precise computation of Global Navigation Satellite Systems （GNSS） per~ manent station velocities in a stable Eurasian reference framework. This allowed computation of the coordinates, variance and covariance matrixes, and horizontal and vertical velocities of the 36 permanent sites analyzed, together with the strain rates, and using different techniques. Interesting geodynamic phenomena are presented, including compressional, and deformational fields in the Tyrrhenian coastal sites of Calabria, extensional trends of the Ionian coastal sites, and sliding movement of the Crotone Basin. Conversely, on the northern Tyrrhenian side of the network near the Cilento Park area, the usual extensional tectonic perpendicular to the Apennine chain is observed. The large- scale pattern of the GNSS height velocities is shown, which is characterized by general interesting geodynamic vertical effects that appear to be due to geophysical movement and anthropic activity. Finally, the strain-rate fields computed through three different tech- niques are compared.展开更多
In this article,we present a new data collection that combines information about earthquake damage with seismic shaking.Starting from the Da.D.O.database,which provides information on the damage of individual building...In this article,we present a new data collection that combines information about earthquake damage with seismic shaking.Starting from the Da.D.O.database,which provides information on the damage of individual buildings subjected to sequences of past earthquakes in Italy,we have generated ShakeMaps for all the events with magnitude greater than 5.0 that have contributed to these sequences.The sequences under examination are those of Irpinia 1980,Umbria Marche 1997,Pollino 1998,Molise 2002,L’Aquila 2009 and Emilia 2012.In this way,we were able to combine,for a total of the 117,695 buildings,the engineering parameters included in Da.D.O.,but revised and reprocessed in this application,and the ground shaking data for six different variables(namely,intensity in MCS scale,PGA,PGV,SA at 0.3s,1.0s and 3.0s).The potential applications of this data collection are innumerable:from recalibrating fragility curves to training machine learning models to quantifying earthquake damage.This data collection will be made available within Da.D.O.,a platform of the Italian Department of Civil Protection,developed by EUCENTRE.展开更多
Phlogopite solid-solutions have a wide pressure-temperature(P-T)stability field and are ubiquitous in a wide variety of geological settings,from deep lithosphere magmatic environments to upper crust metamorphic domain...Phlogopite solid-solutions have a wide pressure-temperature(P-T)stability field and are ubiquitous in a wide variety of geological settings,from deep lithosphere magmatic environments to upper crust metamorphic domains.Phlogopite composition represents therefore a valuable physical-chemical archive and may provide important information regarding its crystallization and the petrogenesis of the host-rock.In this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from St.Helier(Island of Jersey,UK).Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning,however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti(average TiO_(2)≈8.5 wt.%)cores enveloped by euhedral low-to mid-amplitude zonation due to oscillatory contents in Ti,Fe and Mg.Thermo-barometry modelling based on biotite-only composition yields relatively high P-T estimates(T≈970±54℃at P≈0.73±0.13 GPa)for cores whereas lower values(T≈790±54℃at P≈0.29±0.13 GPa)are obtained for the outer rims.Comparable temperatures(T≈1075±54℃)but extremely high and anomalous pressure values(P≈1.82±0.13 GPa)are obtained for the yellowish inner rims.The combination of electron micro probe(EMP)analysis and single-crystal infra-red(FTIR)imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution,typical of crystallization and growth processes of HP/HT environments.Raman imaging provides additional insight for this process,confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer rims.Interpretation of thermobaric estimates obtained from the phlogopite compositiononly model,based on the fine-scale compositional evolution,shows that pressure-temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocally related to pressure-temperature variation of the crystallizing environment.Our results demonstrate how a multidisciplinary approach based on the combination of chemical investigations and vibrational spectroscopies could represent a valuable tool to evaluate pressure-temperature estimates from biotite composition-only thermo-barometry models and therefore to correctly unravel HP/HT petrogenetic processes at a very fine scale。展开更多
In May 2012 a seismic sequence occurred in Northern Italy that was characterized by two main shocks with a magnitude range between 5.5 and 6. These shocks represent a good case study by which to quantify the monetary ...In May 2012 a seismic sequence occurred in Northern Italy that was characterized by two main shocks with a magnitude range between 5.5 and 6. These shocks represent a good case study by which to quantify the monetary losses caused by a moderate earthquake in a densely populated and economically well-developed area.The loss estimation accounts for damage to residential buildings, and considers the full effect of all the seismic aftershock events that lasted for nearly a month. The building damage estimation is based on the European Macroseismic Scale(EMS-98) definitions, which depict the effects of an earthquake on built-up areas in terms of observed intensities. Input data sources are the residential building census provided by Istituto Nazionale di Statistica—the Italian National Institute of Statistics(ISTAT)—and the official market value of real estate assets, obtained from the Osservatorio del Mercato Immobiliare—the Real Estate Market Observatory(OMI). These data make it possible to quantify the economic losses due to earthquakes, an economic indicator updated yearly. The proposed multidisciplinary method takes advantage of seismic,engineering, and economic data sets, and is able to provide a reasonable after the event losses scenario. Data are not gathered for each single building and the intensity values are not a simple hazard indicator, but, notwithstanding its coarseness, this method ensures both robust and reproducible results. As the local property value is availablethroughout the Italian territory, the present loss assessment can be effortlessly repeated for any area, and may be quickly reproduced in case of future events, or used for predictive economic estimations.展开更多
文摘This work identifies the branch point, which was never explicit in EM treatises, from which came the choice of abandoning the Galilean transformations in favor of the Lorentz covariance, a path that originated the various relativistic theories. The need arising from the expanding Earth for a hydrodynamic mechanism for Newtonian and Coulomb fields is discussed. This hydrodynamic material mechanism is shown to constitute a completion of the Newton and Maxwell concepts of the fields, which were only a phenomenological description of physical reality. It is shown that the analogy between Maxwell’s equations and hydrodynamics cannot become a perfect correspondence. The lack of coupling of the electromagnetic field to the underlying material “causing field”—which induces hydrodynamical forces and accelerations observed only phenomenologically—gives rise to inaccuracies in the formulation of its equations, which are incorrect for Galilean covariance. But the most serious flaw in the original formulation of electromagnetism is the erroneous identification of the flow velocity of the field (variable as 1/r2) with the speed of light c, with which it was demonstrated that the fields of charges in motion contract in the direction of motion (the Heaviside ellipsoid, 1888, 1889). From this error, historically due to the incomplete development of many hydrodynamics sectors (a situation that persists today), came Fitz Gerald’s contractions and finally, the relativistic theories. Some future research lines are proposed for a return to realistic physics and a possible but still weak form of Galilean covariance.
基金Centre for Atmospheric Research,Nigeria,for providing the research grant required to conduct this study。
文摘Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work, we present a comprehensive investigation of the performances of two antennas(the u-blox ANN-MB and the TOPGNSS TOP-106) used on a low-cost GNSS receiver known as the u-blox ZED-F9P. The two antennas were installed on two identical and co-located u-blox receivers. Data used from both receivers cover the period from January to June 2022. Results from the study indicate that the signal strengths are dominantly greater for the receiver with the TOPGNSS antenna than for the receiver with the ANN-MB antenna, implying that the TOPGNSS antenna is better than the ANN-MB antenna in terms of providing greater signal strengths. Summarily, the TOPGNSS antenna also performed better in minimizing the occurrence of cycle slips on phase TEC measurements. There are no conspicuous differences between the variances(computed as 5-min standard deviations) of phase TEC measurements for the two antennas, except for a period around May-June when the TOPGNSS gave a better performance in terms of minimizing the variances in phase TEC. Remarkably, the ANN-MB antenna gave a better performance than the TOPGNSS antenna in terms of minimizing the variances in pseudorange TEC for some satellite observations. For precise horizontal(North and East) positioning, the receiver with the TOPGNSS antenna gave better results, while the receiver with the ANN-MB antenna gave better vertical(Up) positioning. The errors for the receivers of both antennas are typically within about 5 m(the monthly mean was usually smaller than 1 m) in the horizontal direction and within about 10 m(the monthly mean was usually smaller than 4 m) in the vertical direction.
基金supported partially by the National Science and Technology Major Project of the Ministry of Science and Technology of China(Nos.2021YFA0719003,2019YFA0708501)funds from Chinese Academy of Sciences as a visiting professorship for senior international scientists(No.2018VMA0007)。
文摘During ancient times,human interest in naturally-occurring gases was religious,while it was scientific in the historical age and industrial in modern times.Gases were also utilized for practical purposes and more than 3000 years before present day,Chinese populations made use of methane for salt extraction while in the 17th century it was observed that native Americans ignited methane seepages.The development of human thinking on gases followed the fundamental steps that characterized the natural sciences during the 18th century scientific revolution that was based on significant improvements in analytical methods.These improvements are still ongoing while present-day scientific publications evidence the spread of the field of interest and more cooperation with geophysical sciences to solve common interest problems.The existence of proper meetings and dedicated scientific journals confirms that gas geochemistry has ended this pioneering phase to enter a more mature condition.
基金funded by a research agreement between the Swiss Seismological Service(SED)and the Istituto Nazionale di Geofisica e Vulcanologiathe RISE project under the European Union’s Horizon 2020 research and innovation programme(Grant No.821115)financed by a SNSF Ambizione Energy grant(PZENP2160555)。
文摘In this work,an approach is developed to study the seismicity associated with the impoundment and level changes of a water reservoir(reservoir induced seismicity e RIS).The proposed methodology features a combination of a semi-analytical poroelastic model with an earthquake nucleation approach based on rate-and-state frictional law.The combined approach was applied to the case of the Pertusillo Lake,located in the Val d’Agri area(Italy),whose large seasonal water level changes are believed to induce protracted micro-seismicity(local magnitude ML<3).Results show that the lake impoundment in 1962 could have produced up to 0.5 bar(1 bar=100 kPa)changes in Coulomb failure stress(DCFS),while the seasonal water level variation is responsible for variation up to 0.05 bar.Modeling results of the seismicity rates in 20012014 show that the observed earthquakes are well correlated with the modeled DCFS.Finally,the reason that the seismicity is only observed at southwest of the Pertusillo Lake is provided,which is likely attributed to different rock lithologies and depletion caused by significant hydrocarbon exploitation in the northeastern sector of the lake.
基金partially supported by the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists(2018VMA0007)
文摘Earthquake is a sudden release of energy due to fault motions.The severity of the damages can be minimized by development of a culture of prevention which includes the Seismic Hazard Assessment,microzonation studies and appropriate building codes.
文摘Machine learning is becoming increasingly important in scientific and technological progress,due to its ability to create models that describe complex data and generalize well.The wealth of publicly-available seismic data nowadays requires automated,fast,and reliable tools to carry out a multitude of tasks,such as the detection of small,local earthquakes in areas characterized by sparsity of receivers.A similar application of machine learning,however,should be built on a large amount of labeled seismograms,which is neither immediate to obtain nor to compile.In this study we present a large dataset of seismograms recorded along the vertical,north,and east components of 1487 broad-band or very broad-band receivers distributed worldwide;this includes 629,0953-component seismograms generated by 304,878 local earthquakes and labeled as EQ,and 615,847 ones labeled as noise(AN).Application of machine learning to this dataset shows that a simple Convolutional Neural Network of 67,939 parameters allows discriminating between earthquakes and noise single-station recordings,even if applied in regions not represented in the training set.Achieving an accuracy of 96.7,95.3,and 93.2% on training,validation,and test set,respectively,we prove that the large variety of geological and tectonic settings covered by our data supports the generalization capabilities of the algorithm,and makes it applicable to real-time detection of local events.We make the database publicly available,intending to provide the seismological and broader scientific community with a benchmark for time-series to be used as a testing ground in signal processing.
文摘Earth Science observations and the Borexino and KamLAND geoneutrino experiments provide clues on the role of aether in the evolution of the Earth, planets, and all other universal structures. Analysis of the problem of storage of aether entering celestial bodies led to a hydrodynamic explanation of gravitation which in turn was found to be closely related to the expanding Earth and to several other phenomena. Variable radius paleogeography provides an approximate assessment of the quantity of ordinary matter added to the planet per time unit, and some inferences about the Earth’s inner energy balance. The aether density, flow rate, and velocity are computed with the help of astrophysics. The origins of cosmological and gravitational redshift are unified under the single cause of gravitation. This is linked to the similar but not interchangeable concept of tired light, which was considered very plausible by cosmologists like Edwin Hubble and Fritz Zwicky. A superluminal speed was calculated for aether at the Earth’s surface. INFN experiments confirm hydrodynamic gravitation and superluminal velocities, and it is possible to identify interrelations of aether parameters with the currently known cosmological parameters H<sub>0</sub>, G, and c. Unification of hydrodynamic gravitation and the expansion of the celestial bodies through the existence of a minor dissipative force, a non-Newtonian concept, involves a revision of the theories of physics and cosmology, in which the currently accepted laws of physics will be only considered good approximations of a more complex reality.
文摘Seismic data of earthquakes recorded during the last 40 years in southern Calabria have been compared with geological data in order to obtain a seismotectonic picture of the area. We sought for any possible correlation between the main regional tectonic structures, the distribution of earthquake hypocentres and the focal mechanism of earthquakes with magnitude(Ml)≥3.Studies of historical and recent seismicity and analysis of geological structures allowed to define the main shear strips on a regional scale. More than 2600 earthquakes with 1.5 ≤ Ml ≤ 4.5 have been considered. The focal mechanisms of earthquakes with Ml≥3 have been compared with the kinematics of known faults and used to give insight on the current active stress field. From the analysis carried out it was possible to expand the cognitive framework regarding the activity of the main tectonic structures present in the area. This study also served to identify areas of high seismicity which do not correspond to any evidence of tectonic structures on the surface, and areas where recognized tectonic structures have not shown any seismicity during the last decades. These cases could be the subject of future investigation in order to correctly assess the seismic hazard in Calabria.This task is important in the context of seismic hazard evaluation and mitigation.
文摘The tectonics and geodynamics of the Calabria region are presented in this study. These are inferred by precise computation of Global Navigation Satellite Systems （GNSS） per~ manent station velocities in a stable Eurasian reference framework. This allowed computation of the coordinates, variance and covariance matrixes, and horizontal and vertical velocities of the 36 permanent sites analyzed, together with the strain rates, and using different techniques. Interesting geodynamic phenomena are presented, including compressional, and deformational fields in the Tyrrhenian coastal sites of Calabria, extensional trends of the Ionian coastal sites, and sliding movement of the Crotone Basin. Conversely, on the northern Tyrrhenian side of the network near the Cilento Park area, the usual extensional tectonic perpendicular to the Apennine chain is observed. The large- scale pattern of the GNSS height velocities is shown, which is characterized by general interesting geodynamic vertical effects that appear to be due to geophysical movement and anthropic activity. Finally, the strain-rate fields computed through three different tech- niques are compared.
文摘In this article,we present a new data collection that combines information about earthquake damage with seismic shaking.Starting from the Da.D.O.database,which provides information on the damage of individual buildings subjected to sequences of past earthquakes in Italy,we have generated ShakeMaps for all the events with magnitude greater than 5.0 that have contributed to these sequences.The sequences under examination are those of Irpinia 1980,Umbria Marche 1997,Pollino 1998,Molise 2002,L’Aquila 2009 and Emilia 2012.In this way,we were able to combine,for a total of the 117,695 buildings,the engineering parameters included in Da.D.O.,but revised and reprocessed in this application,and the ground shaking data for six different variables(namely,intensity in MCS scale,PGA,PGV,SA at 0.3s,1.0s and 3.0s).The potential applications of this data collection are innumerable:from recalibrating fragility curves to training machine learning models to quantifying earthquake damage.This data collection will be made available within Da.D.O.,a platform of the Italian Department of Civil Protection,developed by EUCENTRE.
基金the grant to Department of Science,Roma Tre University(MIUR-Italy Dipartimenti di Eccellenza,ARTICOLO 1,COMMI 314-337 LEGGE 232/2016)。
文摘Phlogopite solid-solutions have a wide pressure-temperature(P-T)stability field and are ubiquitous in a wide variety of geological settings,from deep lithosphere magmatic environments to upper crust metamorphic domains.Phlogopite composition represents therefore a valuable physical-chemical archive and may provide important information regarding its crystallization and the petrogenesis of the host-rock.In this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from St.Helier(Island of Jersey,UK).Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning,however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti(average TiO_(2)≈8.5 wt.%)cores enveloped by euhedral low-to mid-amplitude zonation due to oscillatory contents in Ti,Fe and Mg.Thermo-barometry modelling based on biotite-only composition yields relatively high P-T estimates(T≈970±54℃at P≈0.73±0.13 GPa)for cores whereas lower values(T≈790±54℃at P≈0.29±0.13 GPa)are obtained for the outer rims.Comparable temperatures(T≈1075±54℃)but extremely high and anomalous pressure values(P≈1.82±0.13 GPa)are obtained for the yellowish inner rims.The combination of electron micro probe(EMP)analysis and single-crystal infra-red(FTIR)imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution,typical of crystallization and growth processes of HP/HT environments.Raman imaging provides additional insight for this process,confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer rims.Interpretation of thermobaric estimates obtained from the phlogopite compositiononly model,based on the fine-scale compositional evolution,shows that pressure-temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocally related to pressure-temperature variation of the crystallizing environment.Our results demonstrate how a multidisciplinary approach based on the combination of chemical investigations and vibrational spectroscopies could represent a valuable tool to evaluate pressure-temperature estimates from biotite composition-only thermo-barometry models and therefore to correctly unravel HP/HT petrogenetic processes at a very fine scale。
基金the project ‘‘The Economic Assessment of Natural Disasters in Italy’’ (La valutazione economica dei disastri naturali in Italia, in Italian) funded by Fondazione Generali from 2013 to 2017
文摘In May 2012 a seismic sequence occurred in Northern Italy that was characterized by two main shocks with a magnitude range between 5.5 and 6. These shocks represent a good case study by which to quantify the monetary losses caused by a moderate earthquake in a densely populated and economically well-developed area.The loss estimation accounts for damage to residential buildings, and considers the full effect of all the seismic aftershock events that lasted for nearly a month. The building damage estimation is based on the European Macroseismic Scale(EMS-98) definitions, which depict the effects of an earthquake on built-up areas in terms of observed intensities. Input data sources are the residential building census provided by Istituto Nazionale di Statistica—the Italian National Institute of Statistics(ISTAT)—and the official market value of real estate assets, obtained from the Osservatorio del Mercato Immobiliare—the Real Estate Market Observatory(OMI). These data make it possible to quantify the economic losses due to earthquakes, an economic indicator updated yearly. The proposed multidisciplinary method takes advantage of seismic,engineering, and economic data sets, and is able to provide a reasonable after the event losses scenario. Data are not gathered for each single building and the intensity values are not a simple hazard indicator, but, notwithstanding its coarseness, this method ensures both robust and reproducible results. As the local property value is availablethroughout the Italian territory, the present loss assessment can be effortlessly repeated for any area, and may be quickly reproduced in case of future events, or used for predictive economic estimations.
