In Italy, research in historical seismology has resulted over time in a wealth of studies and data on the seismic history of the country and neighbouring areas.
Such information, although often synthesized and homogenized as macroseismic intensities (i.e. the effects at a given place of a given earthquake evaluated according to a certain macroseismic scale), is actually contained in a variety of studies and presented b different ways, quantities and formats.
With the aim of compiling the Italian Macroseismic Database (Database Macrosismico Italiano - DBMI) and the Italian Parametric Earthquake Catalogue (Catalogo Parametrico dei Terremoti Italiani - CPTI) the identification of the reference study among those available for each earthquake is necessary, in order to derive from it robust parameters through appropriate procedures. Such a selection is the result of a careful comparison of the many datasets available that include their identification and comparative analysis.
With this purpose, over the years both the studies used for the compilation of DBMI and CPTI and their alternatives have been inventoried and collected in a database called Italian Historical Macroseismic Archive (ASMI - Archivio Storico Macrosismico Italiano).
The ASMI website grants direct and integrated access to data and information related to 5894 earthquakes occurred in the Italian area from 461 B.C. to 2014, as provided by 365 studies, such as macroseismic studies, on either one or many earthquakes, bulletins, macroseismic field investigations, macroseismic databases, parametric and instrumental catalogues.
ASMI considers all the earthquakes listed in CPTI15 and DBMI15, those below the energy thresholds of CPTI15 and DBMI15 (intensity 5 and/or magnitude 4), and contains information about earthquakes considered as fakes and some traces of earthquakes occurred before the year 1000. ASMI differentiates from CPTI15/DBMI15 mainly because it contains and makes available one or more studies on each earthquake, providing a panorama of the multiplicity of the existing information, whereas DBMI15 and CPTI15 propose the results of the analysis, selection, and elaboration of such a multiplicity by means of a single record for each earthquake. As another main difference, CPTI and DBMI are updated on a multi-annual base, while ASMI is continuously updated whenever a new study is made available.
Scheme representing the data workflow and the relation among ASMI, DBMI and CPTI.
ASMI is accessible either by earthquake or by study.
The query by earthquake makes the selection of a single earthquake possible either from a list - which can be filtered by year or time span, number of intensity data (if available), or by magnitude classes - or from a map - by selecting the symbol for the epicentre or by defining a circular or polygonal area. The query by earthquake gives access to the information derived from the archived studies. In the window that opens selecting an earthquake, the “Catalogue” tab shows the parameters as defined in CPTI15 (if it lists the earthquake) and many other alternative and/or previous catalogues. The bibliographical reference of each catalogue is presented together with the main parameters; the epicentres defined by each catalogue can be visualized, individually or together with those from other catalogues on the map, selecting the corresponding symbol.
The tab “Studies” lists all the studies archived in ASMI and dealing with the selected earthquake; the study contributing data to DBMI15 is highlighted. The bibliographic reference of each study is shown together with the number of intensity data points (if available), which can be displayed in the map to the left, and their maximum intensity. ASMI presents the content of each study in different ways according to its own characteristics. Most of the studies are available as downloadable PDF files or as a link to an external webpage. Downloadable PDF files consist of either the entire study or parts related to single earthquakes when they are complete and freestanding from the point of view of the earthquake information. The content of many studies, mostly recent ones structured as short descriptive texts on individual earthquakes is directly presented in the webpage, and downloading the PDF files is not necessary (although they are available). The number of studies presented in such a way will progressively increase. On the contrary, studies published in copyrighted journals or books cannot be made available. In such cases, together with the full reference of the study, as in all the other cases, the link to the study’s webpage is provided, if existing. In addition, according to each study’s own characteristics and availability, abstracts of scientific papers and tables of content of books are always provided.
The tab “Seismicity” shows, both on a map and in a time-magnitude chart, the earthquakes located in a definable area around the selected earthquake. To simplify the search through the archive, the earthquakes in both the map and the chart are all selectable.
The query by study is possible through the bibliographic list (which can be filtered by author and/or by year of publication) of the archived studies. The selection of a study gives access to a window from which it is possible, when allowed, to download the study itself as a PDF file or to open the original webpage through its link. The window of the study also shows the earthquakes contained in ASMI and derived from the selected study, both as a map and a list. Through the map and the list it is possible to select an earthquake and to have access to the same information obtained from the query by earthquake. The list shows the main earthquake parameters, indicates whether the study is the one selected for the compilation of CPTI15, and gives access to the portion of the study that deals with the listed earthquake, if possible.
ASMI is part of the portal European Archive of Historical Earthquake Data (AHEAD), the European node for the collection and distribution of historical earthquake data in the framework of the European Plate Observing System (EPOS) initiative.