Gianluca Valensise

National Institute of Geophysics and Volcanology | INGV · Section of Seismology and Tectonophysics

Taking full advantage of good-quality historical earthquake and seismogenic source data available for Italy (Catalogo Parametrico dei Terremoti Italiani [CPTI15] and Database of Individual Seismogenic Sources [DISS] databases), we tested the regional variability of the b-value of the Gutenberg–Richter law, focusing on the dominantly extensional, ne...

Plain Language Summary The Northern Apennines chain is characterized by thrust faults running from the Po Plain to the Adriatic Sea on the northeastern side of peninsular Italy. These thrusts are buried below ≈2,000 m cover of Plio‐Pleistocene deposits. Controversies arose about these thrust faults' activity and earthquake potential based on their...

The Italian historical earthquake record is among the richest worldwide; as such it allows for the development of advanced techniques for retrieving quantitative information by calibration with recent earthquakes. Building on a pilot elaboration of northern Italian earthquakes, we developed a procedure for determining the hypocentral depth of all I...

The development of structurally controlled basins is frequently dominated by inherited geological and tectonic structures, especially when the affected region has undergone multiple tectonic phases. In this study we use physically scaled analog models to analyze the impact of inherited faults on the evolution of a new extensional fault system and i...

All'inizio del 2018 è stata pubblicata una nuova versione del Catalogo dei Forti Terremoti in Italia e nell'area mediterranea, denominata CFTI5Med (Guidoboni et al., 2018). La nuova versione giunge a 11 anni dalla precedente versione (Guidoboni et al., 2007) e ad oltre vent'anni dalla prima uscita (Boschi et al., 1995). Il CFTI, che è basato su una...

We present a review of the assessment of earthquake hazard in Italy, with special reference to the relationships between hazard models and building codes. After early attempts at hazard assessment in the 19th century, the 28 December 1908, Messina Straits earthquake prompted the inception of the first national seismic legislation, passed in early 1...

The Italian historical earthquake record is among the richest worldwide; as such it allows the development of advanced techniques for retrieving quantitative information by calibration with recent earthquakes. Building on a pilot elaboration of northern Italy earthquakes, we developed a procedure for determining the focal depth of all Italian earth...

We investigated the spatial relationships among 18 known seismogenic faults and 1,612 wells drilled for gas exploitation in the main hydrocarbon province of northern-central Italy, a unique dataset worldwide. We adopted a GIS approach and a robust statistical technique, and found a significant anticorrelation between the location of productive well...

In recent years, new approaches for developing earthquake rupture forecasts (ERFs) have been proposed to be used as an input for probabilistic seismic hazard assessment (PSHA). Zone-based approaches with seismicity rates derived from earthquake catalogs are commonly used in many countries as the standard for national seismic hazard models. In Italy...

There is growing interest in how geofluid emissions are released in the atmosphere by the planet’s geodynamic activity, and how much they contribute to the global budget of greenhouse gases. Many workers are addressing this issue with studies conducted at global scale, so as to get the required global-scale answers. The data available at the global...

Large earthquakes occur rather orderly in space and time; hence they can be somehow anticipated, and their effects can be projected into the future. The modern practice of seismic hazard assessment rests on these principles and may rely on them, but also requires a detailed knowledge of the location and characteristics of individual earthquake sour...

Determining the hypocentral depth of pre-instrumental earthquakes is a long-standing geophysical issue that still awaits to be elucidated. Using very well documented recent earthquakes we found that the depth of crustal and upper-mantle events correlates well with the slope of the first 50 km of their intensity attenuation curve, regardless of thei...

A key element for assessing seismic hazard and risk is the availability of a comprehensive dataset on past earthquakes. Here we present the rationale, structure and contents of CFTI5Med ( https://doi.org/10.6092/ingv.it-cfti5 ), the 2018 version of the Catalogue of Strong Earthquakes in Italy: a large multidisciplinary effort including historians,...

We adopted a multidisciplinary approach to investigate the seismotectonic scenario of the 30 October 2016, Mw 6.5, Norcia earthquake, the largest shock of the 2016–2017 central Italy earthquake sequence. First, we used seismological and geodetic data to infer the dip of the main slip patch of the seismogenic fault that turned out to be rather low‐a...

The Catalogo dei Forti Terremoti in ltalia (Catalogue of Strong Italian Earthquakes) is the most important outcome of a well-established collaboration between the Istituto Nazionale di Geofisica (ING; since 2000 Istituto Nazionale di Geofisica e Vulcanologia, INGV), the leading Italian institution for basic and applied research in seismology and so...

Subduction of old Ionian seafloor beneath the Calabrian Arc (southern Italy) is the geological process with the greatest mass flux in the central Mediterranean, yet its seismogenic behavior is largely obscured. No unambiguous evidence of subduction-related earthquakes exists in historical times, and local GPS velocities indicate very low strain rat...

Una delle principali attività svolte tra il 2016 e il 2017 nell’ambito delll'Allegato B2 dell’Accordo-Quadro DPC-INGV 2012-2021 ha riguardato il grande patrimonio informativo sugli effetti ambientali sismo-indotti presente nella banca-dati del Catalogo dei Forti Terremoti in Italia (CFTI). Questi dati sono solo in minima parte accessibili nella sua...

La necessità di rendere disponibili i risultati delle attività svolte tra il 2016 e il 2017 nell’ambito della Convenzione B2 INGV-DPC (Obiettivo 1 - Task A) e la scelta di rendere accessibili contenuti nora non pubblici presenti nella banca dati CFTI (Catalogo dei Forti Terremoti in Italia, Guidoboni et al., 2007), hanno reso indispensabile lo svil...

In: C. Monaco, C. Faccenna, B. Orecchio, A. Polonia and L. Torelli (eds.), "Geodinamica attiva e recente dell'Arco Calabro e del complesso di accrezione nel Mar Ionio"

The 2016–2017 Central Italy earthquakes have shown that the local seismic risk is dominated by the extreme vulnerability of the building stock. We attempt to rank the vulnerability of Apennines' settlements based on a combined geological-historical approach. We first discuss the reasons of the apparent paradox caused by the very different seismic r...

On 24 August 2016 a Mw 6.0 earthquake marked the beginning of a severe seismic sequence that struck Central Italy. This shock was followed by a Mw 5.9 on 26 October, by a Mw 6.5 on 30 October, by two Mw 5.4 aftershocks and by over 30,000 smaller shocks. Based on the widespread occurrence of surface breaks the majority of workers agreed that this se...

p> We show and discuss the similarities among the 2016 Amatrice (Mw 6.0), 1997 Colfiorito-Sellano (Mw 6.0-5.6) and 2009 L’Aquila (Mw 6.3) earthquakes. They all occurred along the crest of the central Apennines and were caused by shallow dipping faults between 3 and 10 km depth, as shown by their characteristic InSAR signature. We contend that these...

We use wet-clay analogue models to investigate how pre-existing discontinuities (i.e. structures inherited from previous tectonic phases) affect the evolution of a normal fault at the Earth’s surface. To this end we first perform a series of three reference experiments driven by a 45° dipping master fault unaffected by pre-existing discontinuities...

The vast majority of active faulting studies are performed at the scale of individual, presumably seismogenic faults or fault strands. Most SHA approaches and models, however, require homogeneus information on potential earthquake sources over the entire tectonic domain encompassing the site(s) of interest. Although it is out of question that accur...

The growth of natural faults is controlled by several factors, including the nature of host rocks, the strain rate, the temperature, and the presence of fluids. In this work we focus on the mechanical characteristics of host rocks, and in particular on the role played by thin mechanical discontinuities on the upward propagation of faults and on ass...

The European Database of Seismogenic Faults (EDSF; doi: 10.6092/INGV.IT-SHARE-EDSF) was compiled in the framework of the EU Project SHARE and is now one of the building blocks of the Hazard & Risk pillar of the EU Project EPOS-IP (WP8, TCS Seismology). EDSF includes faults that are deemed to be capable of generating earthquakes of magnitude equal t...

While scientists are paying increasing attention to the seismicity potentially induced by hydrocarbon exploitation, so far, little is known about the reverse problem, i.e. the impact of active faulting and earthquakes on hydrocarbon reservoirs. The 20 and 29 May 2012 earthquakes in Emilia, northern Italy (Mw 6.1 and 6.0), raised concerns among the...

The 2013 European Seismic Hazard Model (ESHM13) results from a community-based probabilistic seismic hazard assessment supported by the EU-FP7 project “Seismic Hazard Harmonization in Europe” (SHARE, 2009–2013). The ESHM13 is a consistent seismic hazard model for Europe and Turkey which overcomes the limitation of national borders and includes a th...

The 2013 European Seismic Hazard Model (ESHM13) results from a community- based probabilistic seismic hazard assessment supported by the EU-FP7 project “Seismic Hazard Harmonization in Europe” (SHARE, 2009–2013). The ESHM13 is a consistent seismic hazard model for Europe and Turkey which overcomes the limitation of national borders and includes a t...

All in all, the article by CC13 appears as the result of a process of crude simplification, something unacceptable from the point of view of historical criticism and hence of historical seismology. In a further oversimplification of complex facts, CC13 discussed only the evidence available for the 22 February 1346 shock, neglecting the hypothesis o...

This version of the Database contains 126 Individual Seismogenic Sources, 167 Composite Seismogenic Sources, 35 Debated Seismogenic Sources, and three subductions. All sources are based on geological/geophysical data and cover the whole Italian territory and portions of all adjacent countries and seas. This version incorporates several updated sour...

We present a systematic and updated overview of a seismotectonic model for the Po Plain (northern Italy). This flat and apparently quiet tectonic domain is, in fact, rather active as it comprises the shortened foreland and foredeep of both the Southern Alps and the Northern Apennines. Assessing its seismic hazard is crucial due to the concentration...

Several mountainous regions are currently affected by syn- or post-orogenic active extension. We investigate how a newly-formed normal fault interacts with structures inherited from a previous contractional phase. To this end, we use analog models that adopt an innovative technique for performing a precut that mimics such inherited structures into...

Most damaging earthquakes come as complex sequences characterized by strong aftershocks, sometimes by foreshocks and often by multiple mainshocks. Complex earthquake sequences have enormous seismic hazard, engineering and societal implications as their impact on buildings and infrastructures may be much more severe at the end of the sequence than j...

While scientists are paying increasing attention to the seismicity potentially induced by hydrocarbon exploitation, little is known about the reverse problem, i.e. the impact of active faulting and earthquakes on hydrocarbon reservoirs. The recent 2012 earthquakes in Emilia, Italy, raised concerns among the public for being possibly human-induced,...

Over the past few years the assessment of the earthquake potential of large continental faults has increasingly relied on field investigations. State-of-the-art seismic hazard models are progressively complementing the information derived from earthquake catalogs with geological observations of active faulting. Using these observations, however, re...

Over the past few years the assessment of the earthquake potential of large continental faults has increasingly relied on field investigations. State-of-the-art seismic hazard models are progressively complementing the information derived from earthquake catalogues with geological observations of active faulting. Using these observations, however,...

The catastrophic 28 December 1908, Mw 7.1, Messina Straits earthquake was generated by a large, low-angle, SE-dipping, blind normal fault. A number of shallow, high-angle normal faults arranged in a graben-like fashion occur in the same area both on land and offshore, reaching the surface and in some instances affecting recent deposits. These fault...

We present an overview of the seismogenic source model of the Adriatic domain included in the latest version of the DISS database (http://diss.rm.ingv.it/diss/) and in the European SHARE database (http:// diss.rm.ingv.it/SHARE/). The model consists of Composite and Individual Seismogenic Sources located inside and along the margins of the Adria pla...

Understanding the relationship between seismogenic slip at depth and surface defor- mation is fundamental in any seismic hazard analysis because the assessment of the earthquake potential of large continental faults relies largely on field investigations. The well-documented 6 April 2009, Mw 6.3, L’Aquila earthquake affords a unique opportunity to...

The European Database of Seismogenic Faults (EDSF) was compiled in the framework of the EU Project SHARE, Work Package 3, Task 3.2. EDSF includes only faults that are deemed to be capable of generating earthquakes of magnitude equal to or larger than 5.5 and aims at ensuring a homogenous input for use in ground-shaking hazard assessment in the Euro...

This work aims at providing an updated and augmented view of present-day tectonics and seismogenic sources of the Abruzzi Apennines, focusing on its extensional domain. This paper was spurred by the 6 April 2009, L'Aquila earthquake (M-w 6.3), an event from which geologists learned important lessons-including rather surprising ones. Although the ea...

For decades, alluvial plains have been the areas of the fastest population growth over most of the globe. Modern societies demand growing extensions of flat and easily accessible land to accommodate the swelling urban areas, booming industrial districts, large power plants, and multi-runway airports. But how can we tell if such flat areas hide larg...

On May 20 and 29, 2012, two earthquakes of magnitudes 5.9 and 5.8 (Mw), respectively, and their aftershock sequences hit the central Po Plain (Italy), about 40 km north of Bologna. More than 2,000 sizable aftershocks were recorded by the Isti-tuto Nazionale di Geofisica e Vulcanologia (INGV; National Institute of Geophysics and Volcanology) Nationa...

We present a strategy for obtaining fault-based maximum observable shaking (MOS) maps, which represent an innovative concept for assessing deterministic seismic ground motion at a regional scale. Our approach uses the fault sources supplied for Italy by the Database of Individual Seismogenic Sources, and particularly by its composite seismogenic so...

The EC-funded project SHARE (Seismic Hazard Harmonization in Europe) aims at delivering a new model of seismic hazard assessment that is both highly innovative in terms of procedures and input data and fully harmonized across national boundaries. One of the most significant innovations brought about by SHARE is the creation of an authoritative comm...

Historical earthquakes of the Gargano Promontory, an uplifted foreland sector in southeastern Italy, have been usually regarded as generated by inland faults. Some have been associated with activity of the Mattinata fault, a section of a regional east-west shear zone. The 10 August 1893 M-w 5.4 event is one such earthquake, but its current onshore...

As part of the GEM initiative, the EU Project SHARE (http://www.share-eu.org/) has recently completed a task (Task 3.2) devoted to compiling a database of seismogenic sources for the Euro-Mediterranean area. The final release of the database includes about one thousand records of fully parameterized crustal fault sources for a total mapped length o...

A reliable Probabilistic Tsunami Hazard Assessment (PTHA) requires an enormous computational effort. We are developing an approach for limiting the computational burden while trying to preserve the variability of the tsunamigenic seismic sources. We split the PTHA into two stages: linear PTHA and nonlinear PTHA. In the first stage, we explore a lar...

Terra Nova, 23, 108–115, 2011 We analysed a broad region around L'’Aquila in search of seismogenic faults similar to that responsible for the 6 April 2009 earthquake (Mw 6.3). Having in mind the lessons learned from this earthquake, we focused on adjacent areas displaying similar morphotectonic, geological and structural features. The basin running...

We find that the genesis of San Clemente Island and its surrounding submarine platform is consistent with progressive slip on two, southeast-striking, southwest-dipping, blind thrust fault segments. Since their inception 2 to 5 Ma, 3 km of compression normal to the N150°E fault strike has been accommodated with 1700 m of domal uplift of the San Cle...

Terra Nova, 23, 421–423, 2011 AbstractWe reply to a comment by Messina et al., who strongly criticized our article on the San Pio Fault, by showing that in areas of complex geology such as the central Apennines, where the current tectonic setting results from the superposition of different tectonic regimes, the equation: `most visible active fault...

We investigate the role of the Africa-Eurasia convergence in the recent tectonic evolution of the central Mediterranean. To this end we focused on two sectors of the Adriatic-Hyblean foreland of the Apennine-Maghrebian chain as they allow tectonic evidence for relative plate motions to be analyzed aside from the masking effect of other more local t...

We present series of 2Danalogue and numerical models reproducing the tectonic evolution of a low angle (30°), blind, normal fault. The experiments investigate both newly formed structures and strain distribution in the hangingwall of the modelled fault, to identify and discuss a general mechanism underlying this setup. Our case study is represented...

We present our latest achievements in the making of a seismogenic source model for the Euro-Mediterranean area to be used in P SHA. Data incorporated into the model are stored in a database that is being made available to the public through a web-based GIS application. This effort is being driven by the EU P roject SHARE (http://www.share-eu.org/)...

We present preliminary results of a Probabilistic Tsunami Hazard Analysis (PTHA) for the coast of eastern Sicily. We only consider earthquake-generated tsunamis. We focus on important cities such as Messina, Catania, and Augusta. We consider different potentially tsunamigenic Source Zones (SZ) in the Mediterranean basin, basing on geological and se...

In the Catalogue of Strong Italian Earthquakes, all testimonies relating to effects on the environment have been systematically analysed, geo-referenced and filed. This complex work of research and organisation has been conducted according to two main perspectives: the historical and the geological point of view. As regards the historical point of...

Annals of Geophysics, 43, 4, 609-868 (with database on CD-ROM)

Some earthquakes, particularly the strongest ones, can re-occur within hundreds or thousands of years. Therefore, the areas whose "seismic history" seems to be totally lacking in information are indeed a problem. In the past, these "silences" were interpreted in the simplest way, as an indicator of a low degree of seismicity. More recently, the res...

The Gubbio Basin is a 22 km long, 4 km wide depression located within the North-Central Apennines fold-andthrust belt. The basin is bounded to the east by the Gubbio Fault, a W-dipping, normal fault dissecting a large Jurassic-Oligocene anticline. Although located along one of the main seismogenic zones of the Peninsula, both historical and instrum...

The Po Plain is a low-relief area characterised by active shortening accommodated by blind thrust faulting. In this almost flat region depositional rates are similar to tectonic rates and deformation is seldom expressed by noticeable surface anticlines. We adopted a geomorphological approach based on the detailed analysis of the drainage network to...

We present a marine palaeoseismology analysis of a dense network of very high resolution seismic profiles along the Gondola Fault Zone (GFZ), a right-lateral, E–W-striking, active fault system in the Adriatic foreland. This case-study aims to show how time and space variations in the activity of a dominantly right-lateral fault system can be assess...

The outermost, NE-verging fronts of the Northern Apennines (Italy) are overlain by a thick syntectonic sedimentary wedge filling up the basin beneath the Po Plain. Due to fast sedimentation rates and comparatively low tectonic rates, the fronts are generally buried. Evidence for their activity includes scattered historical and instrumental earthqua...

The elevation changes, the seismographic recordings and the damage distribution associated with the disastrous 28 December 1908, Messina Straits, Southern Italy earthquake (Mw 7.1) have been used jointly by seismologists to derive a robust model of the seismogenic source. It consists of a 40 km-long, 30°SE-dipping normal fault extending between 3 a...