Claudio Satriano

Paris Institute of Earth Physics · Department of Seismology

The 11 April 2012 Mw 8.6 earthquake offshore Sumatra is the largest of the rare great intraplate earthquakes of the instrumental era. This major strike-slip event occurred in the diffuse zone of deformation that accommodates differential rotation between Indian and Australian plates. We perform a back projection analysis – calibrated with well- loc...

Earthquake ruptures stop when they encounter barriers impeding further propagation. These barriers can theoretically originate from changes of geometry or nature of the seismic faults, or from a strong lowering of the tectonic stresses, typically due to the occurrence of a recent major earthquake. We show here that this latter mechanism can be inef...

We investigate the rupture process of the 25 April 2015 Gorkha earthquake (Mw=7.9) using a kinematic joint inversion of teleseismic waves, strong-motion data, high-rate GPS, static GPS and SAR data. The rupture is found to be simple in terms of coseismic slip and even more in terms of rupture velocity, as both inversion results and a complementing...

Plain Language Summary In most models and analyses, small earthquakes (i.e., magnitude less than 4) are considered either point sources or homogeneous “penny‐shaped” surfaces. While these assumptions may be valid, details of earthquake ruptures are more complex. Here we study a magnitude 3 induced earthquake that occurred in the St. Gallen geotherm...

Climate change is increasingly predisposing polar regions to large landslides. Tsunamigenic landslides have occurred recently in Greenland ( Kalaallit Nunaat ), but none have been reported from the eastern fjords. In September 2023, we detected the start of a 9-day-long, global 10.88-millihertz (92-second) monochromatic very-long-period (VLP) seism...

A major aim in the study of crustal fluids is the development of automatic methodologies for monitoring deep‐source, non‐volcanic gas emissions’ spatio‐temporal evolution. Crustal fluids play a significant role in the generation of large earthquakes and the characterization of their emissions on the surface can be essential for better understanding...

Quantifying the effect of external forcings like seismicity or rain on slope destabilization is a long-standing and challenging issue. To investigate the respective roles of these forcings, we analyze an unprecedented 10-year long catalog of rockfalls occurring in the crater of the Piton de la Fournaise volcano (La Reunion Island), using statistica...

Seismic hazard levels used as reference for the French Lesser Antilles are derived from probabilistic seismic hazard assessment studies performed in 2002. However, scientific knowledge has greatly increased over the past 20 years in this area, warranting an update of the seismic hazard models. As part of a project linking the French Ministry of Eco...

The accurate characterization of microearthquake sequences allows seismologists to better understand the physical processes involved in earthquake nucleation and rupture propagation and to gain insights on fault geometry at depth. Standard procedures for seismic sequences analysis are based on manual detection and phase-picking, requiring a huge am...

The seismic crisis that began in May, 2018 off the coast of Mayotte announced the onset of a volcanic eruption that started two months later 50 km southeast of the island. This seismicity has since been taken as an indicator of the volcanic and tectonic activity in the area. In response to this activity, a network of stations was deployed on Mayott...

Seismology is one of the main sciences used to monitor volcanic activity worldwide. Fast, efficient, and accurate seismicity detectors are crucial to assess the activity level of a volcano in near-real time and to issue timely warnings. Traditional real-time seismic processing software uses phase onset pickers followed by a phase association algori...

The retrieval of earthquake finite-fault kinematic parameters after the occurrence of an earthquake is a crucial task in observational seismology. Routinely-used source inversion techniques are challenged by limited data coverage and computational effort, and are subject to a variety of assumptions and constraints that restrict the range of possibl...

In May 2018, a seismically quiet region of the Indian Ocean awoke. More than 130 magnitude 4+ earthquakes were recorded in the first month, including a MW 5.9 event on May 15th, 2018. This seismic activity was later identified as being related to an exceptional underwater volcanic eruption offshore Mayotte Island, which had emitted more than 6.5 km...

The M=8.1, April 1st, 2014 Iquique earthquake, which broke part of the northern Chile seismic gap, was preceded by a strong foreshock sequence starting early January 2014. The reported analysis of the continuous records of the nearby GPS stations from the IPOC North Chili array lead to contradictory results concerning the existence and location of...

Instrumental catalogues of earthquakes in the subduction zone of the Lesser Antilles are produced by local observatories and the International Seismological Centre. But none of these catalogues merge all arrival times of the first regional phases available; in addition, they have a magnitude of completeness relatively high for the entire Lesser Ant...

Volcanic eruptions shape Earth’s surface and provide a window into deep Earth processes. How the primary asthenospheric melts form, pond and ascend through the lithosphere is, however, still poorly understood. Since 10 May 2018, magmatic activity has occurred offshore eastern Mayotte (North Mozambique channel), associated with large surface displac...

The brutal onset of seismicity offshore Mayotte island North of the Mozambique Channel, Indian Ocean, that occurred in May 2018 caught the population, authorities, and scientific community off guard. Around 20 potentially felt earthquakes were recorded in the first 5 days, up to magnitude Mw 5.9. The scientific community had little pre-existing kno...

The retrieval of earthquake finite-fault kinematic parameters after the occurrence of an earthquake is a crucial task in observational seismology. Routinely-used source inversion techniques are challenged by limited data coverage and computational effort, and are subject to a variety of assumptions and constraints that restrict the range of possibl...

The eastern offshore of Martinique is one of the active areas of the Lesser Antilles Subduction Zone (LASZ). Although its seismicity is moderate compared to other subduction zones, LASZ is capable of generating a M 7+ interplate earthquake and recent studies and historical events, such as the M8 1839 and M 7-7.5 1946 earthquakes, confirm this possi...

The Résif project, which started in 2008, aims at gathering under a common research infrastructure the French seismological, Global Navigation Satellite Systems and gravimeter permanent networks, as well as the mobile instrument pools. A central part of Résif is its seismological information system, Système d'Information de Résif (Résif-SI) (starte...

Since May 2018, a major volcano-seismic crisis has been happening offshore Mayotte Island, in the Comoros archipelago. With 5.8 km 3 of magma emitted from a deep reservoir, intense seismic activity and deformation that hasn't stopped after more than 2 years, this crisis is unprecedented and represent the largest basaltic eruption in erupted volume...

On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to...

On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to...

Human activity causes vibrations that propagate into the ground as high-frequency seismic waves. Measures to mitigate the COVID-19 pandemic caused widespread changes in human activity, leading to a months-long reduction in seismic noise of up to 50%. The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic...

The 2014 Iquique seismic crisis in Chile, culminating with a Mw 8.1 earthquake on 1 April, highlights a complex unlocking of the Northern Chilean subduction that has been considered a seismic gap since 1877. During the year preceding this event, at least three clusters of seismic activity have been reported: in July 2013 and January and March 2014....

Low-frequency earthquakes are a particular class of slow earthquakes that provide a unique source of information on the physical processes along a subduction zone during the preparation of large earthquakes. Despite increasing detection of these events in recent years, their source mechanisms are still poorly characterised, and the relation between...

The High Agri Valley is a tectonically active area in southern Italy characterized by high seismic hazard related to fault systems capable of generating up to M=7 earthquakes (i.e. the 1857 Mw=7 Basilicata earthquake). In addition to the natural seismicity, two different clusters of induced microseismicity were recognized to be caused by industrial...

The High Agri Valley is a NW-SE trending quaternary basin located in the axial zone of the southern Apennines (Italy). The area is characterized by natural and anthropogenic seismicity and, therefore, it can be considered as a laboratory to deepen the understanding of driving processes of both natural and anthropogenic earthquakes and to develop or...

PUBLISHED : https://www.nature.com/articles/s41598-020-63584-6 Low-frequency earthquakes are a particular class of slow earthquakes that provide a unique source of information on the mechanical properties of a subduction zone during the preparation of large earthquakes. Despite increasing detection of these events in recent years, their source mec...

The High Agri Valley is a tectonically active area in southern Italy characterized by high seismic hazard related to fault systems capable of generating up to M=7 earthquakes (i.e., the 1857 Mw 7 Basilicata earthquake). In addition to the natural seismicity, two different clusters of induced microseismicity were recognized to be caused by industria...

High-frequency (HF) seismic radiation is associated with abrupt changes of rupture velocity and slip-rate during earthquake faulting. Many studies have attempted to illuminate rupture heterogeneities of large earthquakes through the use of coherent imaging techniques such as the back-projection (BP) [e.g. Satriano et al. (2014), Lay et al. (2012)]....

The Mayotte island (Indian Ocean, Comoros archipelago) is undergoing an exceptional offshore volcano-tectonic seismic crisis which started May 10th, 2018, peaked with a magnitude Mw5.9 on the 15th of the same month, and has produced more than two thousand M4+ events to date (Bertil 2019). To monitor this crisis, since February 2019, several French...

Volcanic eruptions are foundational events shaping the Earth's surface and providing a window into deep Earth processes and composition. Most eruptions occur on established volcanoes, exploiting longstanding magma reservoirs and pathways. Those creating new volcanoes are rare and usually too small or too remote to be well monitored, particularly in...

The objective of this work is to interpret the relation between the heterogeneities of the rupture process and the high-frequency (HF) seismic radiation by using the back-projection (BP) imaging technique. Understanding the nature of HF emissions becomes crucial not only in the study of earthquake rupture mechanism, by revealing its complexity, but...

We have analysed the impact of different forcings, such as rain and seismicity, on slope instabilites on an active volcano. For this, we compiled a catalog of the locations and volumes of rockfalls in the Piton de la Fournaise crater using seismic records. We validated it by comparing the locations and volumes to those deduced from photogrammetric...

In this study, we demonstrate the capability of an automatic network-based detection and location method to extract and analyse different components of tectonic tremor activity by analysing a 9-day energetic tectonic tremor sequence occurring at the down-dip extension of the subducting slab insouthwestern Japan. The applied method exploits the cohe...

The Valparaiso 2017 sequence occurred in the Central Chile mega-thrust, an active zone where the last mega-earthquake occurred in 1730. Intense seismicity started 2 days before the Mw 6.9 main-shock, a slow trench-ward movement was observed in the coastal GPS antennas and was accompanied by foreshocks and repeater-type seismicity. To characterize t...

We present a new methodology for detection and space-time location of seismic sources based on multiscale, frequency-selective coherence of the wave field recorded by dense large-scale seismic networks and local antennas.The method is designed to enhance coherence of the signal statistical features across the array of sensors and consists of three...

The 2014 Iquique seismic crisis, culminating with the main Mw 8.2 Iquique earthquake (Chile), 1st of April 2014, and the largest Mw 7.7 aftershock, 3rd of April, highlighted a complex unlocking of the North Chile subduction interface. Indeed, during many months preceding this event, at least three large seismic clusters have been observed, in July...

The issue of earthquake source scaling continues to draw considerable debate within the seismological community: observation supporting and refuting that systematic differences between the source processes of small and large earthquakes are still discussed. This motivates the study of how source parameters, such as seismic moment and corner frequen...

Since the collapse of the Dolomieu crater floor at Piton de la Fournaise Volcano (la Réunion) in 2007, hundreds of seismic signals generated by rockfalls have been recorded daily at the Observatoire Volcanologique du Piton de la Fournaise (OVPF). To study rockfall activity over a long period of time, automated methods are required to process the av...

We present a 1-D velocity model of the Earth's crust in Campania–Lucania region obtained by solving the coupled hypocentre–velocity inverse problem for 1312 local earthquakes recorded at a dense regional network. The model is constructed using the VELEST program, which calculates 1-D ‘minimum’ velocity model from body wave traveltimes, together wit...

The improvements in high-density, high-dynamics and broadband seismic observation make it possible to investigate the proprieties of microearthquake source parameters at very small scales, in order to better understand the earthquake process similarity over a broad magnitude range. The issue of earthquake source scaling continues to draw considerab...

Due to the increment in local and regional seismological and geodesy networks, new technics for imaging extended sources have been developed and open up new ways to understand the source dynamic. One of those technics uses the coherent interferometry of the wave radiation emitted during the ruptured propagation at dense arrays; producing imaging of...

The analysis of similar earthquakes, such as events in a seismic sequence, is an effective tool with which to monitor and study source processes and to understand the mechanical and dynamic states of active fault systems. We are observing seismicity that is primarily concentrated in very limited regions along the 1980 Irpinia earthquake fault zone...

Supplementary Information of: Stabile, T. A., Satriano, C., Orefice, A., Festa, G., and Zollo, A. (2012). “Anatomy of a microearthquake sequence on an active normal fault”, Scientific reports, 2, Art. N. 410. doi: 10.1038/srep00410

Anatomy of a microearthquake sequence on an active normal fault - Supplementary Information

In this paper we introduce an optimization scheme for choosing the most appropriate set of parameters for a picking algorithm by using real picks and data acquired by a specific seismic network. The optimal model is chosen through searching in the global parameter space of the maximum of an objective function that depends on the comparison between...

We introduce a general purpose, broadband phase detector and picker algorithm (FilterPicker) that is applicable to real-time seismic monitoring and earthquake early warning. This algorithm is loosely based on the Baer and Kradolfer (1987) picker and on the Allen picker (Allen 1978, 1982). The FilterPicker algorithm is designed so that it operates s...

In recent years the seismic observation has made a huge leap forward in terms of coverage and density of recording stations. This instrumental effort has fostered the development of new approaches to the study of the seismic rupture, which can potentially support and complement the classical finite source kinematic modeling. The availability of d...

In recent years a new approach to earthquake rupture imaging has emerged, based on the exploitation of the coherency of the seismic signal recorded at modern seismic networks. A dense station deployment can be used as an antenna to track the energy radiated by the propagating rupture along the fault. This energy, coherently recorded at the stations...

The great 11 March 2011 Off the Pacific Coast of Tohoku earthquake (Mw 9.1) ruptured a ~ 200 km wide mega-thrust fault, with average displacement of ~15-20 m. The earthquake triggered a large devastating tsunami as well as strong ground motion along the east Honshu coastline. Seismic activity in this area is characterized by a number of large earth...

Simplified one-dimensional velocity models are generally used both for monitoring and for research purposes in geologically complex seismogenic areas. In these situations the use of 1D models to represent the true three- dimensional velocity distribution can lead to systematic errors in the estimated earthquake locations and focal mechanisms. This...

Modern technology allows real-time seismic monitoring facilities to evolve into earthquake early warning (EEW) systems, capable of reducing deaths, injuries, and economic losses, as well as of speeding up rescue response and damage recovery. The objective of an EEW system is to estimate in a fast and reliable way the earthquake’s damage potential,...

PRESTo (PRobabilistic and Evolutionary early warning SysTem) is a software platform for regional earthquake early warning that integrates recently developed algorithms for real-time earthquake location and magnitude estimation into a highly configurable and easily portable package. The system is under active experimentation in Southern Italy on the...

We investigated the rupture process of the 2010 Mw 8.8 Maule earthquake by back projecting teleseismic body waves energy recorded at several worldwide seismic stations and arrays. This approach, being a signal-processing technique, does not require any a-priori knowledge or assumption on the source (hypocentral location, origin time, rupture veloci...

The Mw 8.8 earthquake in central Chile ruptured more than 400 km along the subduction bound between the Nazca and the South American plates. The aftershock distribution clearly shows that this earthquake filled a well-known seismic gap, corresponding to rupture extension of the 1835 earthquake. The triggered post-seismic activity extends farther no...

The Campi Flegrei caldera (southern Italy) is one of the most hazardous areas in the World as several hundred thousand people live there and where important socio-economic activities have developed. The caldera includes the western-most part of the city of Naples and extends into the Gulf of Pozzuoli (eastern Tyrrhenian basin; Fig. 1). The main fea...

The Irpinia Seismic Network (ISNet) is deployed in Southern Apennines along the active fault system responsible for the 1980, November 23, M s 6.9 Campania–Lucania earthquake. It is set up by 28 stations and covers an area of about 100 × 70 km2. Each site is equipped with a 1-g full-scale accelerometer and a short-period velocimeter. Due to its des...

This work concerns the high-resolution study of Irpinia region through the refined estimates of micro-earthquake source parameters in the magnitude range 1<M<3 and the determination of appropriate velocity models. Using accurate manual picks we first located about 900 events using a non-linear global approach and after we refined locations consider...

S5 project was aimed at supporting and integrating the ongoing research on three selected Italian test sites (the Alto Tiberina Fault (ATF), the Messina Strait and the Irpinia fault system) where advanced multi-parametric monitoring infrastructures are available. A new site (L’Aquila) has been added to the S5 project in September 2009 after the occ...

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