The IT framework of the European Archive of Historical Earthquake Data (AHEAD)

The European Archive of Historical EArthquake Data (AHEAD) has been developed in the frame of the EC project NERIES and maintained in the frame of the EC project SHARE.AHEAD makes available on the web the result of a networked historical earthquake data research, formalised in terms of studies (papers, reports, macroseismic data points, etc). It provides an updated wealth of data that are unique for many European events in the time-window 1000-1963.A series of IT solutions have been developed in order to support both the research and the networking activities carried out within the building process of AHEAD. The resulting framework is an equally balanced effort in both the back-end and front-end design and implementation, a key feature in a research approach very much human-centred, where the quantity of data is small if compared to terabytes of instrumental data.AHEAD is composed of five mutually dependent data-components: 1) the “Digital Library”, where all the historical earthquake studies are stored and described by bibliographical metadata, 2) the “Consensus Earthquake Inventory”, where the relevant macroseismic data (event date, epicentral area, number of macroseismic data-point, maximum observed intensity) are extrapolated, the best available information are selected and fake earthquakes are highlighted, 3) the “European Macroseismic Database”, where all the available macroseismic data-points (MDPs) are stored, 4) the “Parameters Laboratory”, where earthquakes parameterisation methods are applied to MDPs in order to obtain epicentral locations and magnitudes and 5) the “European Earthquake Catalogue”.The presentation will demonstrate the adopted IT solutions separately for the back-end and the front-end, both for the access-restricted website and the general-purpose implementation designed to be included in the “Earthquake Data Portal”, developed within the EC project NERIES, which targets a much broader scientific community

The University of Athens Hellenic Macroseismic Database for Historical Earthquakes

During the last decade, a systematic study of historical earthquakes leading to the quantification of earthquake effects in terms of macroseismic datapoints (MDPs) and, consequently, to earthquake parameters, has been carried out in the Laboratory of Seismology of the University of Athens. For each earthquake, the available background information has been evaluated and the corresponding macroseismic intensities assessed in terms of EMS98. A considerable amount of studied earthquakes contributed to the Archive of Historical EArthquake Data (AHEAD) and MDPs are now part of its European Macroseismic Database, via European initiatives (NERIES, SHARE). Based on standards proposed by AHEAD, a local database was designed, incorporating historical earthquakes of the period 1000-1899, mainly from the eastern Aegean area. The database includes 93 events with Ix≥7 (683 MDPs) and 1053 events with Ix<7 (1205 MDPs). The data is accessible on the Internet at http://macroseismology.geol.uoa.gr

Assessing the completeness of Italian historical earthquake data

The assessment of the completeness of historical earthquake data (such as, for instance, parametric earthquake catalogues) has usually been approached in seismology - and mainly in Probabilistic Seismic Hazard Assessment(PSHA) - by means of statistical procedures. Such procedures look «inside» the data set under investigation and compare it to seismicity models, which often require more or less explicitly that seismicity is stationary. They usually end up determining times (Ti), from which on the data set is considered as complete above a given magnitude (Mi); the part of the data set before Ti is considered as incomplete and, for that reason, not suitable for statistical analysis. As a consequence, significant portions of historical data sets are not used for PSHA. Dealing with historical data sets - which are incomplete by nature, although this does not mean that they are of low value - it seems more appropriate to estimate «how much incomplete» the data sets can be and to use them together with such estimates. In other words, it seems more appropriate to assess the completeness looking «outside » the data sets; that is, investigating the way historical records have been produced, preserved and retrieved. This paper presents the results of investigation carried out in Italy, according to historical methods. First, the completeness of eighteen site seismic histories has been investigated; then, from those results, the completeness of areal portions of the catalogue has been assessed and compared with similar results obtained by statistical methods. Finally, the impact of these results on PSHA is described

CALIBRACIÓN Y VALIDACIÓN DEL ALGORITMO DE BAKUN AND WENTWORTH PARA CALCULAR LOCALIZACIÓN Y MAGNITUD DE TERREMOTOS HISTÓRICOS A PARTIR DE DATOS MACROSÍSMICOS EN CUBA ORIENTAL

We present the results of a calibration analysis performed on eastern Cuba seismicity datasets of the approach proposed by Bakun and Wentworth (1997) to bound earthquakes epicentral area and magnitude from MSK macroseismic data only. The calibration is required as the algorithm derives an intensity magnitude (equal in the mean to moment magnitude Mw) from macroseismic observations by using a regionally suitable attenuation relationship of intensity as a function of Mw and source distance. To this purpose, a training set of 8 Post-900 earthquakes occurred in eastern Cuba was selected, for which a large number of intensity observations and reliable instrumental determinations of Mw and epicentral location are available. The model is given by: IMSK = (3.11±0.40)+(1.40±0.09)*Mw-(0.0017±0.00027)*R-(3.17±0.20)*LogR where R is the hypocentral distance in kilometres, the model is calibrated for earthquakes in the range of 5.22≥Mw≥6.81, hypocentral distances less than 400km and fixed depth at 10km. The model is validated using the 1947, 1976 and 1998 earthquakes, which were not used in the calibration process and also have instrumental data. The validation of the algorithm demonstrates reliability and applicability of the method for the analysis of historical earthquakes that have no records of instrumental parameters. An overall agreement is found for both the location and magnitude of these events with magnitude uncertainties between 0.23 and 0.35 equivalent to two standard deviations. However the MDPs distributions are partially azimuthal for those 11 analyzed earthquakes, the model can reproduce offshore epicentres within acceptable uncertainties ranges. A first application is made to a historical earthquake occurred on June 6, 1766 causing severe damage to the city of Santiago de Cuba. keywords: Macroseismic Data Points (MDPs), Macroseismic intensity attenuation, earthquake parameters, CubaSe presentan los resultados de un análisis de calibración, a partir de bases de datos de sismicidad del oriente de Cuba, del algoritmo de Bakun y Wentworth (1997) para delimitar área epicentral y magnitud a partir de solo datos de intensidad macrosísmica en escala MSK. La calibración es necesaria debido a que el algoritmo calcula una magnitud a partir de puntos de intensidad macrosísmica mediante el uso de un modelo regional de atenuación de la intensidad macrosísmica en función de Mw y de la distancia a la fuente. Para este propósito, se seleccionaron ocho terremotos del post-900, para los cuales se dispone de 486 observaciones de intensidad macrosísmica y determinaciones instrumentales confiables de magnitud de momento sísmico (Mw) y epicentro. El modelo obtenido es: IMSK = (3.11±0.40)+(1.40±0.09)*Mw-(0.0017±0.00027)*R-(3.17±0.20)*LogR donde R es la distancia hipocentral en kilómetros, calibrado para sismos en el rango de 5.22≥Mw≥6.81, distancias hipocentrales menores de 400 km y profundidad fija a 10 km. El modelo de atenuación es validado utilizando tres eventos ocurridos en 1947, 1976 y 1998 los cuales no fueron utilizados en el proceso de calibración y además cuentan con datos instrumentales. Las magnitudes calculadas con nuestro modelo son comparables con las instrumentales para los ocho terremotos utilizados para la calibración como también para los tres sismos usados en el proceso de validación con incertidumbres entre 0.23 y 0.35 equivalentes a dos desviaciones estándar. No obstante ser la distribución de puntos de intensidad parcialmente azimutal para los 11 terremotos analizados, el modelo logra reproducir epicentros de carácter costa afuera dentro de rangos de incertidumbres aceptables. La validación del algoritmo demuestra confiabilidad y aplicabilidad del método para el análisis de terremotos históricos que no tienen registros de parámetros instrumentales. Una primera aplicación es realizada a un terremoto histórico ocurrido el 6 de junio del 1766 que ocasionó graves daños a la ciudad de Santiago de Cuba. palabras clave:&nbsp;Puntos de intensidad macrosísmica, Atenuación de la Intensidad, macrosísmica, parámetros del terremoto, Cuba. &nbsp; &nbsp

The 2013 European Seismic Hazard Model: key components and results

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 through quantification of the uncertainties. It is the first completed regional effort contributing to the “Global Earthquake Model” initiative. It might serve as a reference model for various applications, from earthquake preparedness to earthquake risk mitigation strategies, including the update of the European seismic regulations for building design (Eurocode 8), and thus it is useful for future safety assessment and improvement of private and public buildings. Although its results constitute a reference for Europe, they do not replace the existing national design regulations that are in place for seismic design and construction of buildings. The ESHM13 represents a significant improvement compared to previous efforts as it is based on (1) the compilation of updated and harmonised versions of the databases required for probabilistic seismic hazard assessment, (2) the adoption of standard procedures and robust methods, especially for expert elicitation and consensus building among hundreds of European experts, (3) the multi-disciplinary input from all branches of earthquake science and engineering, (4) the direct involvement of the CEN/TC250/SC8 committee in defining output specifications relevant for Eurocode 8 and (5) the accounting for epistemic uncertainties of model components and hazard results. Furthermore, enormous effort was devoted to transparently document and ensure open availability of all data, results and methods through the European Facility for Earthquake Hazard and Risk (www.​efehr.​org)

Archivo online de datos macrosísmicos de la península Ibérica

An application has been adopted to visualize macroseismic data of the Iberian Peninsula. Three institutions, Institut Geològic de Catalunya (IGC), Instituto Geográfico Nacional (IGN), from Spain and Instituto de Meteorologia from Portugal have already implemented in their web sites with information on the most important earthquakes. A computer programe (MIDOP, Macroseismic Intensity Data Online Publisher) was created by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in order to easily allow theobtention of Earthquake listing and geographical distribution of intensity data points through a web page

The 2016–2017 earthquake sequence in Central Italy: macroseismic survey and damage scenario through the EMS-98 intensity assessment

In this paper we describe the macroseismic effects produced by the long and destructive seismic sequence that hit Central Italy from 24 August 2016 to January 2017. Starting from the procedure adopted in the complex field survey, we discuss the characteristics of the building stock and its classification in terms of EMS-98 as well as the issues associated with the intensity assessment due to the evolution of damage caused by multiple shocks. As a result, macroseismic intensity for about 300 localities has been determined; however, most of the intensities assessed for the earthquakes following the first strong shock on 24 August 2016, represent the cumulative effect of damage during the sequence. The earthquake parameters computed from the macroseismic datasets are compared with the instrumental determinations in order to highlight critical issues related to the assessment of macroseismic parameters of strong earthquakes during a seismic sequence. The results also provide indications on how location and magnitude computation can be strongly biased when dealing with historical seismic sequences.Presidenza del Consiglio dei Ministri - Dipartimento della Protezione Civile (DPC)Published2407–24314T. Sismicità dell'Italia1SR TERREMOTI - Sorveglianza Sismica e Allerta Tsunami2SR TERREMOTI - Gestione delle emergenze sismiche e da maremoto5SR TERREMOTI - Convenzioni derivanti dall'Accordo Quadro decennale INGV-DPCJCR Journa

Catálogo de terremotos de América del Sur homogéneo en Mw para el periodo pre-1964

On the frame of The South America Risk Assessment (SARA) project, an earthquake catalogue was compiled for South America, in terms of the moment magnitude (Mw), with data from the Centro Regional de Sismología para América del Sur (CERESIS), recent national and international studies, and from the analysis conducted during the project. In particular, it is included the latest versions of catalogue CERESIS-91 prepared by CERESIS and published by the National Council of Science and Technology CONCYTEC of Peru, the determination of parameters by recent studies, including those proposed by the ISC-GEM catalogue, and where available, the national catalogues that meet the criteria of transparency required by the project. The results presented in this work correspond to the pre-1964 time window. The first phase of the study is the development of a critical inventory of all public studies related to earthquakes in South America. Studies for the same event have been associated with each other from the comparison of the time, of the epicentre coordinates and the size of the earthquake (magnitude or maximum seismic intensity). For each event, a set of parameters considered reliable has been preliminarily selected. The main problem of the catalogue is the need to express the values of magnitude in terms of moment magnitude (Mw). Currently, few studies on historical earthquakes provide this value for the study region. For many events, values in terms of Ms and mb are available; although for most cases, because of the time of occurrence of these events, the magnitude values were calculated from macroseismic data. For these earthquakes we have used empirical conversion relationships published in literature for Ms and mb to Mw. There are also events for which only a value of maximum intensity (Imax or Io) is available. For these events, regional relationships Imax to Mw have been determined, using the most reliable and recent data of Mw and Imax values. In a second phase, for some events that have a sufficient number of macroseismic data, the source parameters have (including location, Mw and uncertainties) been determined using the method of Bakun and Wentworth (1997), regionally calibrated, based on what already has been obtained for Ecuador, Venezuela in literature and Colombia in the present project. In this way, the magnitude Mw was evaluated for 2564 earthquakes in South America. The lower threshold is defined in Mw = 5 for the Andean region. For Brazil, a lower threshold was not applied.Published6T. Studi di pericolosità sismica e da maremotoN/A or not JC

The 2014 Earthquake Model of the Middle East: seismogenic sources

The Earthquake Model of Middle East (EMME) project was carried out between 2010 and 2014 to provide a harmonized seismic hazard assessment without country border limitations. The result covers eleven countries: Afghanistan, Armenia, Azerbaijan, Cyprus, Georgia, Iran, Jordan, Lebanon, Pakistan, Syria and Turkey, which span one of the seismically most active regions on Earth in response to complex interactions between four major tectonic plates i.e. Africa, Arabia, India and Eurasia. Destructive earthquakes with great loss of life and property are frequent within this region, as exemplified by the recent events of Izmit (Turkey, 1999), Bam (Iran, 2003), Kashmir (Pakistan, 2005), Van (Turkey, 2011), and Hindu Kush (Afghanistan, 2015). We summarize multidisciplinary data (seismicity, geology, and tectonics) compiled and used to characterize the spatial and temporal distribution of earthquakes over the investigated region. We describe the development process of the model including the delineation of seismogenic sources and the description of methods and parameters of earthquake recurrence models, all representing the current state of knowledge and practice in seismic hazard assessment. The resulting seismogenic source model includes seismic sources defined by geological evidence and active tectonic findings correlated with measured seismicity patterns. A total of 234 area sources fully cross-border-harmonized are combined with 778 seismically active faults along with background-smoothed seismicity. Recorded seismicity (both historical and instrumental) provides the input to estimate rates of earthquakes for area sources and background seismicity while geologic slip-rates are used to characterize fault-specific earthquake recurrences. Ultimately, alternative models of intrinsic uncertainties of data, procedures and models are considered when used for calculation of the seismic hazard. At variance to previous models of the EMME region, we provide a homogeneous seismic source model representing a consistent basis for the next generation of seismic hazard models within the region.Published3465-34966T. Studi di pericolosità sismica e da maremotoJCR Journa