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Main outcomes are reported of the first year of activity of the DPC-INGV-S3 project devoted to explore present situation of earthquake forecasting studies in Italy. The general paradigm beyond the project is that earthquakes are p...
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Main outcomes are reported of the first year of activity of the DPC-INGV-S3 project devoted to explore present situation of earthquake forecasting studies in Italy. The general paradigm beyond the project is that earthquakes are part of a large scale process whose ongoing features can only be detected by considering multi-parametric monitoring of large areas carried on for relatively long time spans. The focus of the first year of activity was on the analysis of the state of the art concerning a number of observables potentially of interest: deep fluids piezometry, seismicity, gaseous ground emissions and temperature, electromagnetic perturbations, short-term geodetic deformation and crustal elastic properties. To evaluate the actual heuristic potential of the above observables as expression of ongoing seismogenic processes, the reappraisal and exploitation of significant data sets collected in the past and relative to these were of main concern. Along these features, deterministic and statistical procedures for medium-term earthquake forecasting were also considered as a tool for detecting areas most interesting for future monitoring activity.
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The aim of this research is to discover a reliable and scientific precursor that is theoretically able to predict all earthquakes, within specified parameters, within a few days, in this case within two days, of the earthquakes - ...
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The aim of this research is to discover a reliable and scientific precursor that is theoretically able to predict all earthquakes, within specified parameters, within a few days, in this case within two days, of the earthquakes - this is more efficient than having a prediction window of months or years. This method has accurately predicted 14 out of 15 earthquakes within specified parameters of location, magnitude and depth, with no false predictions-this is a success rate of 93%. Deviations in the times for a simple pendulum to complete 30 oscillations were analysed and these deviations were used to make earthquake predictions. This is related to plate motion and changes in ‘g’. The parameters of earthquakes predicted include those that occurred in north-eastern Colombia, of magnitude M 4.0 and higher, and depth 100 km or more. Also included in the predictions are earthquakes of similar magnitude, originating at depths of 25 km and more in Antigua and Barbuda, Montserrat and Guadeloupe. Another parameter is that for an earthquake to be accurately predicted it must not occur within 24 hours of the previous one. These earthquakes were predicted within two days of their occurrences. In addition to predicting earthquakes, the data supports the rebound theory, since deviations in times for 30 oscillations return to zero within a day or two after an earthquake-this allows for calculations of rebound velocities. The data also shows that there is a net transfer of lithospheric matter away from the observation point at St. Augustine, Trinidad. This method can be applied anywhere on earth-it is simple to set up, inexpensive, scientific and reliable.
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Recent experiments in ionic crystals reveal that tin the absence of any external electric field) a time-dependent electric polarization arises upon changing the rate of the uniaxial stress or by the indenter penetration into the c...
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Recent experiments in ionic crystals reveal that tin the absence of any external electric field) a time-dependent electric polarization arises upon changing the rate of the uniaxial stress or by the indenter penetration into the crystal surface. The latter experiments lead to activation volumes, which art: order(s) of magnitude smaller than those measured by Lazarus and co-workers [Phys. Rev. B 5, 4935 (1972); Phys. Rev. B 8, 1726 (1973]. We show that this difference is not inconsistent with thermodynamical concepts of point defects. Furthermore, an explanation of the nondetection of the cofracture electric signals at large distances, when the crystal is surrounded by a weakly conducting medium, is suggested. [S0163-1829(99)14801-X]. [References: 14]
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The paper by Taroni et al. (2016) considers results of forward prediction of Italian strong earthquakes by CN algorithm with the declared intent of providing “a careful assessment of CN prediction performances … using standard t...
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The paper by Taroni et al. (2016) considers results of forward prediction of Italian strong earthquakes by CN algorithm with the declared intent of providing “a careful assessment of CN prediction performances … using standard testing procedures.” Given the very limited number of target events within each region, however, the considered situation is non statistical, and a priori it is clear that the standard statistical methods are not effective here. The attempt to replace the standard approaches by Pari-mutuel Gambling Score (PGS) method leads to almost complete loss of information about predicted earthquakes, even for a large sample of target events. Therefore, the conclusions based on PGS, are untenable.?
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This study reports on a possible very low frequency/low frequency (VLF/LF) subionospheric precursor to a recent earthquake in Japan. As the epicenter of this large Japanese earthquake on March 11, 2011, was located just on the gre...
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This study reports on a possible very low frequency/low frequency (VLF/LF) subionospheric precursor to a recent earthquake in Japan. As the epicenter of this large Japanese earthquake on March 11, 2011, was located just on the great-circle path from one of our VLF/LF network stations (Chofu) to the NLK US transmitter, we examined the propagation characteristics mainly associated with the signals from the NLK transmitter, as observed at three of the stations in Japan (Chofu, Kasugai and Kochi). On March 5 and 6, 2011, a remarkable anomaly was found on the path from NLK to Chofu, which is highly likely to have been a precursor to this earthquake. The anomaly in the night-time average amplitude at Chofu was characterized by a serious decrease in the signal that exceeded ?4v (v: standard deviations). The anomaly was found on the same days on the other propagation paths (from NLK to both Kasugai and Kochi), although it was less enhanced. Finally, this propagation anomaly is extensively discussed with respect to the geomagnetic activity, and we also compare this anomaly with the properties related to the former 2004 Sumatra earthquake that had nearly the same magnitude as this March 11, 2011, earthquake. ?
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One of the possible ways of evaluation of the earthquake prediction efficiency is a posterior count of successful predictions compared with the number of all issued predictions and the number of all events which should be predicte...
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One of the possible ways of evaluation of the earthquake prediction efficiency is a posterior count of successful predictions compared with the number of all issued predictions and the number of all events which should be predicted. Two efficiency parameters are in general use: the success rate defined as a percentage of the successful predictions in the total number of issued predictions and the alarm rate defined as a percentage of the successful predictions in the total number of events which should be predicted.
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We treat the earth crust and mantle as large scale discrete matters based on the principles of granular physics and existing experimental observations. Main outcomes are: A granular model of the structure and movement of the earth...
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We treat the earth crust and mantle as large scale discrete matters based on the principles of granular physics and existing experimental observations. Main outcomes are: A granular model of the structure and movement of the earth crust and mantle is established. The formation mechanism of the tectonic forces, which causes the earthquake, and a model of propagation for precursory information are proposed. Properties of the seismic precursory information and its relevance with the earthquake occurrence are illustrated, and principle of ways to detect the effective seismic precursor is elaborated. The mechanism of deep-focus earthquake is also explained by the jamming unjamming transition of the granular flow. Some earthquake phenomena which were previously difficult to understand are explained, and the predictability of the earthquake is discussed. Due to the discrete nature of the earth crust and mantle, the continuum theory no longer applies during the quasi-static seismological process. In this paper, based on the principles of granular physics, we study the causes of earthquakes, earthquake precursors and predictions, and a new understanding, different from the traditional seismological viewpoint, is obtained.
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Rigorous predictability experimentation requires a statistical characterization of the performance metric used to evaluate the participating models. We explore the properties of the area skill score measure and consider issues rel...
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Rigorous predictability experimentation requires a statistical characterization of the performance metric used to evaluate the participating models. We explore the properties of the area skill score measure and consider issues related to experimental discretization. For the case of continuous alarm functions and continuous observations, we present exact analytical solutions that describe the distribution of the area skill score for unskilled predictors, and we also describe how a Gaussian distribution with known mean and variance can be used to approximate the area skill score distribution. We quantify the deviation of the exact distribution from the Gaussian approximation by specifying the kurtosis excess as a function of the number of observed target earthquakes. For numerical earthquake predictability experiments that involve discretization of the study region and observations, we explore simulation procedures for estimating the area skill score distribution, and we present efficient algorithms for various experimental scenarios. When more than one target earthquake occurs within a given space/time/magnitude bin, the probabilities of predicting individual events are not independent, and this requires special consideration. Having presented the statistical properties of the area skill score, we describe and illustrate a preliminary procedure for comparing earthquake prediction strategies based on alarm functions.
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摘要 :
Rigorous predictability experimentation requires a statistical characterization of the performance metric used to evaluate the participating models. We explore the properties of the area skill score measure and consider issues rel...
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Rigorous predictability experimentation requires a statistical characterization of the performance metric used to evaluate the participating models. We explore the properties of the area skill score measure and consider issues related to experimental discretization. For the case of continuous alarm functions and continuous observations, we present exact analytical solutions that describe the distribution of the area skill score for unskilled predictors, and we also describe how a Gaussian distribution with known mean and variance can be used to approximate the area skill score distribution. We quantify the deviation of the exact distribution from the Gaussian approximation by specifying the kurtosis excess as a function of the number of observed target earthquakes. For numerical earthquake predictability experiments that involve discretization of the study region and observations, we explore simulation procedures for estimating the area skill score distribution, and we present efficient algorithms for various experimental scenarios. When more than one target earthquake occurs within a given space/time/magnitude bin, the probabilities of predicting individual events are not independent, and this requires special consideration. Having presented the statistical properties of the area skill score, we describe and illustrate a preliminary procedure for comparing earthquake prediction strategies based on alarm functions.
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After a brief (incomplete) review of pre-seismic (strain-producing) phenomena, we describe our findings about the pre-seismic phase of the the April 6, 2009 L'Aquila earthquake, giving a few more details with respect to previous p...
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After a brief (incomplete) review of pre-seismic (strain-producing) phenomena, we describe our findings about the pre-seismic phase of the the April 6, 2009 L'Aquila earthquake, giving a few more details with respect to previous papers. Most past observations of crustal strain did not detect any pre-seismic deformation and have been used to constrain the size and strength of the source of possible pre-seismic phenomena. With respect to these, we performed a rather more sophisticated approach to the physics of the model; limited the volume of the possible earthquake preparation zone to less than 100 km~3; showed some evidence of dilatancy of saturated rock over the earthquake causative fault (maybe related to the foreshocks) and constrained the prerupture nucleation slip in the hypocentral region to a moment less than 0.00005% of the main shock seismic moment (lowering the previous thresholds).
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