Luciano Telesca

• Italian National Research Council

This study analyzes the temporal dynamics of instrumental seismicity recorded in the Pertusillo reservoir area (Southern Italy) between 2001 and 2018. The Gutenberg–Richter analysis of the frequency–magnitude distribution reveals that the seismic catalog is complete for events with magnitudes M≥1.1. The time-clustering of the sequence is at both gl...

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In this study, the topological properties of the shallow seismicity occurring in the area around the Lai Chau hydropower plant (Vietnam) are investigated by using visibility graph (VG) analysis, a well-known method to convert time series into networks or graphs. The relationship between the seismicity and reservoir water level was analyzed using In...

In this study, we examined how the nonlinearity α of the Langevin equation influences the behavior of extremes in a generated time series. The extremes, defined according to run theory, result in two types of series, run lengths and surplus magnitudes, whose complex structure was investigated using the visibility graph (VG) method. For both types o...

Whenever seismic activity occurs before large earthquakes seismologists refer to such “precursory” events as “foreshocks”. Seismicity tends to take place clustered in space and time regardless of the happening of major events; a vast majority of earthquake clusters is indeed made up of small events; so, it does not flow into a mainshock and the fol...

We perform an analysis to understand what information may be hidden in partial, limited earthquake catalogues only containing mid-size and a few large seismic events (or even no one) about the largest possible ones using clustering properties of recorded events. We consider the local and global coefficients of variation, the scaling exponent of the...

Starting from an initial catalogue of 7833 natural and reservoir-induced seismic events collected in Aswan region (south Egypt) from 1982 to 2016, we investigate the fault structure and triggering mechanisms by determining high-resolution hypocenters for 2562 earthquakes. Despite the complex network of intersecting fractures, highprecision earthqua...

Seismic activity is the mirror of local instability in the brittle crust. Each seismic event occurs as a consequence of stress accumulation at weak interfaces within crustal volumes and static and dynamic perturbations, so that earthquakes tend to be clustered in space and time. So, while on one hand, seismicity trivially provides information about...

Xylella Fastidiosa has been recently detected for the first time in southern Italy, representing a very dangerous phytobacterium capable of inducing severe diseases in many plants. In particular, the disease induced in olive trees is called olive quick decline syndrome (OQDS), which provokes the rapid desiccation and, ultimately, death of the infec...

One of the most intriguing issues in earthquake science concerns the discrimination between foreshocks and swarms. We investigate relocated seismic catalogues in California and Italy and provide a theoretical explanation of our results. Foreshocks and swarms share the same scaling behaviours and are likely generated by the same physical mechanism;...

We perform an analysis to understand what information may be hidden in partial, limited earthquake catalogues only containing mid-size and a few large seismic events (or even no one) about the largest possible ones using clustering properties of recorded events. We consider the local and global coefficients of variation, the scaling exponent of the...

Seismicity occurs because of strain accumulation in the brittle crust due to the action of tectonic forces. However, this background process is just one of numerous ones affecting earthquake occurrence. In the long run it controls the frequency of large events (Neely et al., 2023); conversely, at our time scales it is likely one of the less impactf...

Supplementary Information for the paper "Are foreshocks fore-shocks?"

Plain Language Summary Large earthquakes can be preceded by a wide range of different seismic anomalies. Among these, seismicity has been reported to increase both in magnitude and frequency, but, on the other hand, it can also undergo a short period of reduced intensity before major events. The first pattern corresponds to the occurrence of foresh...

In the context of assessing seismic hazard, accurately predicting ground motion stands out as a crucial task. Achieving precision in ground motion modeling proves valuable in revealing the actual pattern, even when faced with insufficient data on soil structure, provided there is precise information about the seismic source. This study introduces a...

A spectral analysis of the time dynamics of seismicity occurring in the Enguri area of Georgia from 1978 to 2021 is performed by means of Schuster’s spectrum analysis, periodogram analysis, and empirical mode decomposition. The results of our analysis suggest that earthquakes around the reservoir (within a 50 km radius from the center of the dam) m...

The largest earthquakes control large part of the energy budget of seismogenic structures which is progressively accumulated in the adjoining volumes meanwhile the fault system is kept locked. As wide-scale destabilization is approaching, seismic activity may increase, which can produce further instability leading to the mainshock. Foreshocks are t...

Diverse forms of nonlinearity within stochastic equations give rise to varying dynamics in processes, which may influence the behavior of extreme values. This study focuses on two nonlinear models of the discrete Langevin equation: one with a fixed diffusion function (M1) and the other with a fixed marginal distribution (M2), both characterized by...

The simplest model to describe seismic activity assumes that earthquakes occur because of strain accumulation within the brittle crust to be released along weak frictional interfaces, i.e., faults, whose dynamic behaviour can be described by stability conditions, so that large seismic events would occur almost periodically if faults were perfectly...

The time dynamics of the instrumental seismicity recorded in the area of the Lai Chau reservoir (Vietnam) between 2015 and 2021 were analyzed in this study. The Gutenberg-Richter analysis of the frequency-magnitude distribution has revealed that the seismic catalog is complete for events with magnitudes larger or equal to 0.6. The fractal method of...

Faults are weak, geometrically complex, strongly interacting interfaces of crustal volumes dissipating tectonic stress. Earthquake ruptures propagate throughout them following uneven multiple paths, taking jumps and bends producing spatially heterogeneous slip amounts and stress drops. Nevertheless, routinely implemented dynamic and kinematic simul...

In this paper, we examined the dynamical properties of the fluid-injection microseismicity at the Val d’Agri oil field (southern Italy) by applying different statistical methods to find correlations and common periodicities with injection parameters, such as injected volumes and injection pressure. Two periods of observation were analyzed: (1) from...

New clues for seismic hazard from statistical properties of seismicity, rheology and tectonics -XXVIII IUGG General Assembly -Berlin, Germany S14a -New Advances in Understanding the Earth's Crust Dynamics in the Light of Solving the Problem of Earthquake Forecasting

The purpose of this work was to evaluate the potential of Singular Spectrum Analysis (SSA) and the Fisher–Shannon method to analyse NDVI MODIS time series and to capture and estimate inner vegetation anomalies in forest covers. In particular, the Fisher–Shannon method allows to calculate two quantities, the Fisher Information Measure (FIM) and the...

In this work we analyze the influence of nonlinearity on the behavior of extremal values of time series generated by two discrete Langevin models: fixing the diffusion function in the first (M1), the marginal distribution in the second (M2). The extremes were generated by applying the run theory. A mathematical relationship was found between nonlin...

Xylella fastidiosa is a phytobacterium able to provoke severe diseases in many species. When it infects olive trees, it induces the olive quick decline syndrome that leads the tree to a rapid desiccation and then to the death. This phytobacterium has been recently detected in olive groves in southern Italy, representing an important threat to the o...

The Anatolian region is one of the most seismically active tectonic settings in the world. Here, we perform a clustering analysis of Turkish seismicity using an updated version of the Turkish Homogenized Earthquake Catalogue (TURHEC), which contains the recent developments of the still ongoing Kahramanmaraş seismic sequence. We show that some stati...

The Kahramanmaraş seismic sequence has involved several segments of the East Anatolian fault system in Türkiye Its spatial and temporal evolution showcases strong interactions among different fault patches. We characterize such complexity by focusing on the dynamics of the two largest events and their relationship with early aftershock activity. We...

The aim of the present work is to furnish a detailed picture of the space-time-magnitude statistical properties of the instrumental seismic catalogue of Azerbaijan and surrounding regions from 2003 to 2016. Although Azerbaijan is one of the most seismically active areas in the world, an exhaustive description of the statistical properties of the ti...

The estimation of the maximum expected magnitude is crucial for seismic hazard assessment. It is usually inferred via Bayesian analysis; alternatively, the size of the largest possible event can be roughly obtained from the extent of the seismogenic source and the depth of the brittle-ductile transition. However, the effectiveness of the first appr...

Methods used in the article

Since the dawn of earthquake science, a clear split has risen between theoretical seismology and statistical seismology. While the physics of coseismic rupture can be described by using a classical approach, the statistical patterns of seismicity are described by power laws produced by collective processes generated by many-scales nonlinear coopera...

The main goal of this study was to evaluate the potential of the Fisher-Shannon statistical method applied to the MODIS satellite time series to search for and explore any small multiyear trends and changes (herein also denoted as inner anomalies) in vegetation cover. For the purpose of our investigation, we focused on the vegetation cover of three...

In this work the time dynamics of GPS time series recorded at the Campi Flegrei caldera from 2000 to 2019 was investigated by using the Fisher Information Measure (FIM) and the Shannon entropy power (SEP), two informational methods that allow the detection of changes in the dynamical behavior of a complex system, like the volcanic one, quantifying...

The MODIS Aqua and Terra Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) time series acquired during nearly two decades (2000 to 2020) covering the area burned by the Camp Fire (California) in 2018 is investigated in this study by using the multifractal detrended fluctuation analysis in relation to the recovery pro...

Assessing the stability state of fault interfaces is a task of primary interest not only for seismic hazards, but also for understanding how the earthquake machine works. Nowadays it is well known that a relationship exists between slow and fast earthquakes; moreover, it is more and more evident that such a connection is quite diffuse all over the...

Electrical Resistivity Tomography (ERT) is a robust and well-consolidated method largely applied in near-surface geophysics. Nevertheless, the mapping of the spatial resistivity patterns of the subsurface at a depth greater than 1 km was performed in just a few cases by the ERT method, called deep ERT (DERT). Since, in many cases, the term DERT was...

In this study, the visibility graph analysis of seismicity triggered by Song Tranh 2 hydropower (Vietnam) is performed. The relationship between the seismic (the Gutenberg–Richter b-value) and topological (the k–M slope) parameters of seismicity is analysed. Our findings indicate that the relationship between the Gutenberg–Richter b-value and the k...

Since the dawn of the modern science of earthquakes, a clear split has risen among theoretical and statistical seismology and tectonics. Classical seismology explains what happens during a few seconds of fault slip following rock breakdown, with the consequent radiation of seismic waves, while statistical seismology describes how seismicity occurs...

The stability state of fault systems is mainly controlled by the frictional properties of weak interfaces and the available energy accumulated in the volumes beside them. Heterogeneities, roughness, and topological features play a key role in driving seismic dynamics and tectonic stress dissipation. However, the physics of the processes fostering m...

The reservoir-triggered seismicity at the Song Tranh 2 reservoir in Vietnam is investigated by using Shannon entropy, a well-known informational method used to analyze complexity in time series in terms of disorder and uncertainty. The application of the time-varying Shannon entropy to the time series of the interevent times of seismicity has evide...

Vegetation dynamic processes influenced by fires has represented a scientific topic of great importance because of the environmental impact of fires. The use of satellites to investigate vegetational trends has become quite common for the wide coverage and high spatial resolution of satellite images. In this paper, we study the temporal variability...

Faults become more and more responsive to stress perturbations as instability mounts. We utilize this property in order to identify the different phases of the seismic cycle. Our analysis provides new insights about the features of impending mainshocks, which are proposed to emerge from a large-scale crustal-weakening preparation process whose dura...

The Gutenberg-Richter law and the Omori law are both characterized by a scaling behavior. However, their relation is still an open question. Although several hypotheses have been formulated, a comprehensive geophysical mechanism is still missing to explain the observed variability of the scaling exponents b-value and p-value, e.g., correlating the...

Bayesian inference shows that the distribution of the future event not only depends on the past events (prior), but also depends on the relation between the past and the future events (likelihood). However, the classical Bayesian methods do not consider the important contributions of recent data. In this paper, we propose a new Bayesian inference-b...

Neural networks have been successfully applied for modeling time series. However, the results of long-term prediction are not satisfied. In this paper, the modified Meta-Learning is applied to the neural model. The normal Meta-Learning is modified by time-varying learning rates and adding a momentum term to improve convergence speed and robustness...

Featured Application This article introduces a method to establish the state of mechanical stability of a fault system by analyzing modulations of seismic activity as a function of known perturbations, i.e., tidal stress. In addition to providing useful information about the physics of fault systems, our method can be applied to evaluate how unstab...

The prediction of the magnitude of an earthquake is still a challenge in the studies of seismic processes. The machine learning approaches have been developed recently to predict only the magnitude of next incoming earthquake using historical data. In this study, we combine neural networks with the meta-learning to predict not only the magnitude of...

We are currently far from being able to make an accurate and timely prediction of earthquakes, that can tell us even roughly Where will it occur? When will it occur? What will its magnitude be? And at what depth will it occur? However, this information would be incredibly valuable to avoid loss of lives, damage to constructions, and a great economi...

The time dynamics of the instrumental seismicity (1 ≤ ML ≤ 4.7) recorded in the area of Song Tranh 2 reservoir (Vietnam) between September 2012 and March 2020 was analyzed in this study. The daily maximum of the water level was analyzed by means of the periodogram, while the earthquake sequence was analyzed by using the Schuster spectrum, which is...

Changes in climate, land use, and land management impact the occurrence and severity of wildland fires in many parts of the world. This is particularly evident in Europe, where ongoing changes in land use have strongly modified fire patterns over the last decades. Although satellite data by the European Forest Fire Information System provide large-...

Temperature and composition at fumaroles are controlled by several volcanic and exogenous processes that operate on various time-space scales. Here, we analyze fluctuations of temperature and chemical composition recorded at fumarolic vents in Solfatara (Campi Flegrei caldera, Italy) from December 1997 to December 2015, in order to better understan...

The seismo-electrical coupling is critical to understand the mechanism of geoelectrical precursors to earthquakes. A novel seismo-electrical model, called Chen–Ouillon–Sornette (COS) model, has been developed by combining the Burridge–Knopoff spring-block system with the mechanisms of stress-activated charge carriers (i.e., electrons and holes) and...

Atmospheric pollution in Mexico City Metropolitan Area (MCMA) represents a serious social and economic concern due to the very high population density. The most important industrial activities are the main responsible of the production of particulate matter PM10 that can damage seriously the human respiratory system. In the present study we investi...

High frequency data from the city of Petrolina, Northeast Brazil, are used to find the wind speed projection series at different angles, which are then analyzed by using several statistical tools: detrended fluctuation analysis (DFA), multifractal detrended fluctuation analysis (MFDFA) and Fisher–Shannon analysis (FSA). It is found that α, the DFA...

Considerable amount of surface water in Lebanon is stored behind dams, and the Qaraaoun Reservoir (QR) is a typical example. It is the largest surface water body in Lebanon where it irrigates 27,500 ha and generates 22% of Lebanon’s electricity. The reservoir is fed directly from the Litani River which receives water from several springs and from g...

A Bayesian approach has been applied to estimate the distribution of magnitudes, interevent distances and times of earthquakes occurred in 2017 in central Italy by using a small amount of random samples drawn from the distribution of the same seismic parameters for the earthquakes occurred in 2014-2016. We applied the method to the whole and afters...

The temporal variations of the instrumental seismicity (0.5 ≤ML ≤ 3.5) recorded in the Mingechevir area (Azerbaijan) between January 2010 to December 2018 and its relationship with the level variation of the water reservoir was analysed in this study. The monthly number of events was analysed by using the correlogram-based periodogram, the singular...

The intraplate and interplate seismic catalogues of Iquique (Chile) area were investigated by using seismological (b value of the Gutenberg–Richter law), fractal (Allan Factor and detrended fluctuation analysis) and topological (Horizontal Visibility Graph) methods. The two catalogues show different stress state indicated by the different b value,...

We applied the informational approach of the Fisher‐Shannon method to study the time series of Standardized Precipitation Index (SPI) derived from monthly rainfall data at 133 gauging stations in Northeast (NE) Brazil. The climate in the study region ranges from tropical humid in the coastal area Zona de Mata to tropical semiarid inland Sertão, pas...

This study investigates the relationship between the b value of the Gutenberg–Richter law and the so-called k–M slope, a topological parameters, derived from the visibility graph analysis, that recently has been gaining great attention in describing the time dynamics of seismicity. The relationship has been already found to be nearly linear for sev...

An improved pattern informatics (PI) method, inspired by the soup-of-groups model, is developed in this study. This improved method reveals its potential in reducing the noise that, when the classical PI is applied, can yield misleading conclusions about the existence of “hotspots” in the vicinity of the epicenter of a strong earthquake. The applic...

In this study, we investigate the relationship between topological and seismological parameters of earthquake sequences generated by the Olami–Feder–Christensen (OFC) [Olami et al., Phys. Rev. Lett. 68(8), 1244 (1992)] spring-block model and converted in undirected graphs by using the visibility graph method [Lacasa et al., Proc. Natl. Acad. Sci. U...

We analyze the time clustering phenomenon in sequences of extremes of time series generated by the fractional Ornstein-Uhlenbeck (fO-U) equation as the source of long-term correlation. We used the percentile-based definition of extremes based on the crossing theory or run theory, where a run is a sequence of L contiguous values above a given percen...

In this paper seismic hazard for the sourthern slope of the Greater Caucasus (Azerbaijan) was assessed by using five major parameters: moment magnitude, simulated peak ground acceleration (PGA) from four target earthquakes, intensity scenario, amplification factor and b value. The deterministic scenario-based seismic hazard assessment method was ap...

Azerbaijan is characterized by a strong level of seismicity with earthquakes concentrated within several active areas. In this study, we calculated the source mechanism of earthquakes occurring in the northeastern part of Azerbaijan, by using the digital waveform data recorded by the Republican Seismic Survey Center (RSSC) at the Azerbaijan Nationa...

The analysis of vegetation dynamics affected by wildfires contributes to the understanding of ecological changes under disturbances. The use of the Normalized Difference Vegetation Index (NDVI) of satellite time series can effectively contribute to this investigation. In this paper, we employed the methods of multifractal detrended fluctuation anal...

In this paper, the time series of contact force among pedestrians in two different crowding conditions is analysed by using the correlogram-based periodogram and the Fisher–Shannon method to investigate their spectral and informational properties, respectively. The overcrowding was simulated by controlled experiments carried out at University of Sc...

Geoelectric self‐potential (SP) signals are sensitive to natural and anthropogenic factors. The SP spectral characteristics under the different factors in Taiwan were investigated, and the SP spectral scalings were correlated with urbanization level, seismicity, and crustal deformation. The ambient SP noise models were first established by estimati...

In this paper, we analyze the informational properties of time series of slip velocity generated by the Langevin equation of friction in two different frictional regimes: viscous and Coulombian. Representing the generated time series in the Fisher-Shannon plane (where the coordinate axes are the Fisher Information Measure and the Shannon entropy po...

This study aims at investigating several dynamical parameters of the monthly variability of eight streamflow time series, recorded at different stations along the major courses and springs of the Litani River (Lebanon). The contribution of the annual periodicity to the total variance of the series depends on the geomorphological characteristics of...

The 10-min average wind speed series recorded at 130 stations distributed rather homogeneously in the territory of Switzerland are investigated. Fixing a percentile-based threshold of the wind speed distribution, a wind extreme is defined as the duration of the sequence of consecutive wind values above the threshold. This definition allows to analy...

Seismological research importance around the globe is very clear, therefore new tools and algorithms are needed in order to predict magnitude, time and geographic location, as well as found out relationships that allow us to understand better this phenomenon and thus be able tosave countless human lives. However, given the highly random nature of t...

Bayesian statistical procedures are well known for estimating the probability distribution of the occurrence of an event. In this study, we applied the Bayesian statistical method to estimate the distribution of magnitudes of earthquakes that occurred in central Italy in two different time periods. Using the Monte Carlo sampling method, we recovere...

In this study, the 10-min average wind speed series recorded at 132 stations distributed rather homogeneously over the territory of Switzerland were investigated, focusing on the challenging problem of the analysis and modelling of wind extreme events. Wind extremes are defined as a sequence of consecutive values above a percentile-based threshold...

Water scarcity has been well pronounced in the Middle East Region; however, Lebanon is still characterized by wet climate and sufficient water resources. It is a paradox that Lebanon is now under water stress, and many contradictory studies on the climate of Lebanon attributed water stress to the changing climate. Most of these studies were applied...

Complex networks are gaining popularity in describing the cooperative behavior within a complex system involving relationships among its constituent units. A network can easily present a wind speed-monitoring system, by considering the measuring stations as nodes and the links by a linear or non-linear metric. This work presents two applications o...

The safety hazard and the additional costs on transportation due to road accidents invite the necessity to minimize their impact. In this paper, we study the spatial-clustering behavior and hazard vulnerability of car accidents that occurred in Lebanon between 2015 and 2018. Assessment of spatial clustering of accidents and hot spots densities were...

High frequency wind time series measured at different heights from the ground (from 1.5 to 25.5 meters) in an urban area were investigated by using the variance of the coefficients of their wavelet transform. Two ranges of scales were identified, sensitive to two different dynamical behavior of the wind speed: the lower anemometers show higher wave...

A mutual information-based weighted network representation of a wide wind speed-monitoring system in Switzerland was analyzed in order to detect communities. Two communities have been revealed, corresponding to two clusters of sensors situated, respectively, on the Alps and on the Jura-Plateau that define the two major climatic zones of Switzerland...

In this paper, high frequency wind time series measured at different heights from the ground (from 5.5 to 25.5 m) in an urban area were investigated. The spectrum of each series is characterized by a power-law behaviour at low frequency range, with a mean spectral exponent of about 1.5, which is rather consistent with the Kolmogorov spectrum of atm...

In this paper, the time dynamics of the daily means of wind speed measured in complex mountainous regions are investigated. For 293 measuring stations distributed over all Switzerland, the Fisher information measure and the Shannon entropy power are calculated. The results reveal a clear relationship between the computed measures and both the eleva...

Lebanon, with its geographic location facing the Mediterranean Sea and dominant rugged topography, is characterized by a strong climatic variability even between zones located few kilometres apart. The investigation of the climatic indices is necessary to delineate such diverse climatic situation over Lebanon. In this context, this paper investigat...