Seismic hazard map for the Italian territory using macroseismic data

A seismic hazard map, in terms of macroseismic intensity, is proposed for the Italian continental territory and Sicily, which has a 10% probability of exceedance in 50 years. The methodology used here was first proposed by Cornell (1968), which requires information about the location and seismicity rates within each of the defined seismogenic zones, as well as an attenuation model. In particular, it is proposed an original macroseismic intensity attenuation model derived from the Italian macroseismic database DBMI04. The seismic hazard map, obtained in terms of intensity, was subsequently transformed into PGA by means of a linear relation between intensity and PGA, in order to compare it with the national seismic hazard map MPS04

Stima della pericolosità sismica in termini di intensità macrosismica in Italia: due metodologie di calcolo a confronto

N/

Inventario de Daños y Efectos Geológicos Co y/o Post-Sísmicos del Sismo Ocurrido el 18 de mayo de 1875, en la Frontera entre Colombia y Venezuela

On the border between Colombia and Venezuela, have occurred seismic events with important records of damage in both countries. In this paper, we study the historical earthquake that took place on May 18, 1875 between 11.15 and 11.30 in the morning (the time was the same for communities in both countries since there was no time zone difference), which is catalogued as a border earthquake due to the report of damages in the cities of both nations. The community of San José de Cúcuta, current capital of the Northern State of Santander, Colombia, registered the greatest number of deaths and damage to buildings. An inventory of the geological damage and co -seismic and postseismic effects was created based on information of previous studies and data obtained from archival primary sources from Colombia and Venezuela. The result is a bi-national database, which includes the summaries of historical descriptions with the effects in the persons and objects, the geological damages and effects observed during the seismic event. These data has led to the creation of a table of MM and EMS-98 intensities, which enables the identification and delimitation of the regions of greater damages. The maximum level intensity is I=10 in the cities of San José de Cúcuta, Villa del Rosario, Pueblo de Cúcuta (San Luis) in Colombia and San Antonio, San Juan de Ureña in Venezuela. Moreover, we formulated a table of intensities using the ESI-2007 INQUA scale, based on the information of geological observations described in historical documents. These data are related to the epicentral zone with an approximate radius of 30 km.Published105-2635T. Sismologia, geofisica e geologia per l'ingegneria sismicaN/A or not JC

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

DETERMINING THE PARAMETERS OF EARTHQUAKE SOURCES IN SOUTH AMERICA FROM MACROSEISMIC INTENSITY DATA (CERESIS DATABASE)

In the past decades many different procedures have been made to handle the historical data for the determination of the earthquake source parameters. This has been only possible dealing with historical data interpreted and compiled as Intensity Data Points (IDP). One of the most interesting tools is the Boxer algorithm, a parameterisation method that computes the parameters of the earthquake source in terms of latitude and longitude of the epicentre, magnitude of the event, length, width and azimuth of the box, which represent the surface projection of the sismogenic source. Applying the Boxer algorithm we have used intensity data points available from the CERESIS database (earthquakes with I0 ≥ 8MM) to obtain a preliminary idea of the possible sources of some historical earthquakes of the South-American region. At a first approach to the South-American historical seismicity we generally can affirm that our results agree fairly well with seismological data and geological background as reported in literature

Consolidated models for attenuation of macroseismic intensity. Progetto INGV-DPC S2, Deliverable D3.2

INGV-MilanoPublished4.2. TTC - Modelli per la stima della pericolosità sismica a scala nazionalereserve

Stima della pericolosità sismica in termini di intensità macrosismica in Italia: due metodologie di calcolo a confronto

N/APublishedTrieste, Italy4.2. TTC - Modelli per la stima della pericolosità sismica a scala nazionaleope

The determination of earthquake location and magnitude from macroseismic data in Europe

This paper describes how the earthquake parameters of historical earthquakes have been determined in Europe from macroseismic data by means of the so-called \u201cBoxer\u201d method, in the frame of the European Commission 2009\u20132012 Project SHARE (Seismic Hazard Harmonization in Europe). The problems related to the assessment of magnitude are described with more detail; the methodological issues are developed with special reference to the \u201cstable continental region\u201d. The paper first describes how the coefficients of the Boxer method are determined in five tectonic regions of the European area from the relevant calibration data sets, and discusses the problems dealt with while performing this task. Then it describes how the results have been checked against data different from those used in the previous phase. Finally, the application of the new coefficients to nearly a thousand of European earthquakes before 1900 is described. Stressing that, for the first time in Europe, homogeneous results have been obtained at such a large scale, the final part of the paper is devoted to analyse such results, with special reference to the general trends and to some case-histories