The AHEAD Portal: A Gateway to European Historical Earthquake Data

The description of the seismicity of the European region is today fragmented into an increasing number of earthquake archives, databases, and catalogs related to individual countries or even to part of them. Therefore, the compilation of a comprehensive, European earthquake history requires dealing with a puzzle of partially overlapping, only partially public catalogs, the background of which is compiled according to varied schemes. One of the consequences is that earthquakes in the frontier areas are often interpreted in a conflicting way by the catalogs of the bordering countries. In the framework of the European Commission (EC), 2006–2010 Network of Research Infrastructures for European Seismology (NERIES) Project, the task of Networking Activity 4 (NA4) was defined precisely to conceive and develop solutions to bridge over these differences. NA4 promoted the cooperation among existing national online archives, and contributed establishing new regional online archives compiled according to common standards. As a result, a first release of the distributed European archive of historical earthquake data, for the time-window 1000–1899 and for the large earthquakes, was published in 2010. Special attention was devoted to retrieve the earthquake background information, that is, the results of historical earthquake investigation—referenced to as studies in the following -in terms of a paper, a report, a book chapter, a map, etc. As the most useful studies are those supplying a set of macroseismic data points (MDPs)- that is a list of localities (name and coordinates) with a macroseismic intensity assessment and the related macroseismic scale—a dedicated effort was addressed to make such data available. The Archive of Historical Earthquake Data (AHEAD) distributed archive was improved and updated in the frame of the 2010–2012 EC Project Seismic Hazard Harmonization in Europe (SHARE), Task 3.1 European earthquake database, with the contribution of a number of European institutions. For the time window 1000–1899, it was AHEAD (AHEAD Working Group) that supported the compilation of the SHARE European Earthquake Catalog (SHEEC; Stucchi et al., 2013). This paper describes the AHEAD portal (http://www.emidius.eu/AHEAD/; last accessed March 2014), and how it was conceived to network the local components of the distributed archive. Although local historical macroseismic databases usually supply one set of information for each earthquake, at a European scale an earthquake still might be described by several studies, available from different archives. The AHEAD portal inventories and gives access to multiple sets of information concerning each earthquake, and allows users to get comprehensive information about individual earthquakes, providing the answers to the following questions: 1. which sets of earthquake parameters (time, location, magnitude, magnitude type, maximum intensity, etc.) are available for each earthquake? 2. what is the background information, or supporting material, upon which each set of earthquake parameter determination is based

Photoinduced monooxygenation involving NAD(P)H-FAD sequential single-electron transfer

Light-dependent or light-stimulated catalysis provides a multitude of perspectives for implementation in technological or biomedical applications. Despite substantial progress made in the field of photobiocatalysis, the number of usable light-responsive enzymes is still very limited. Flavoproteins have exceptional potential for photocatalytic applications because the name-giving cofactor intrinsically features light-dependent reactivity, undergoing photoreduction with a variety of organic electron donors. However, in the vast majority of these enzymes, photoreactivity of the enzyme-bound flavin is limited or even suppressed. Here, we present a flavoprotein monooxygenase in which catalytic activity is controllable by blue light illumination. The reaction depends on the presence of nicotinamide nucleotide-type electron donors, which do not support the reaction in the absence of light. Employing various experimental approaches, we demonstrate that catalysis depends on a protein-mediated photoreduction of the flavin cofactor, which proceeds via a radical mechanism and a transient semiquinone intermediate

Setting up an earthquake forecast experiment in Italy

We describe the setting up of the first earthquake forecasting experiment for Italy within the Collaboratory for the Study of Earthquake Predictability (CSEP). CSEP conducts rigorous and truly prospective forecast experiments for different tectonic environments in several forecast testing centers around the globe; forecasts are issued for a future period and also tested only against future observations to avoid any possible bias. As such, experiments need to be completely defined. This includes exact definitions of the testing area, of learning data for the forecast models, and of observation data against which forecasts will be tested to evaluate their performance. Here we present the rules, as taken from the Regional Earthquake Likelihood Models experiment and extended or changed for the Italian experiment. We also present characterizations of learning and observational catalogs that describe the completeness of these catalogs and illuminate inhomogeneities of magnitudes between these catalogs. A particular focus lies on the stability of earthquake recordings of the observational network. These catalog investigations provide guidance for CSEP modelers for developing earthquakes forecasts for submission to the forecast experiment in Italy

A WebGIS tool for the dissemination of earthquake data

In 2004 a new seismic hazard map of Italy (MPS Working Group, 2004) has been released by a task force that produced an amount of new or updated data, such as a new version of the earthquake catalogue (CPTI04; CPTI Working Group, 2004) and an updated seismogenic zonation. A set of WebGIS tools has been designed for the data dissemination to the scientific community and the general public. The design of the WebGIS tools focused first on the consultation of the DBM04 macroseismic database (DBM Working Group, 2005), which contains the macroseismic intensity data-points (IDP) of the earthquakes listed in the CPTI04 catalogue. The WebGIS tool design and development process had to fulfill: 1) simplicity, 2) responsiveness and 3) readiness for future extensions. The specific requirements for the macroseismic database consultation interface were: - data access by place and by earthquake; - IDP maps with queryable points; - data download in both tabular and map format; - easily upgradable content; - quick and user friendly interface

Test of structural models for the (4 4) phase formed by oxygen adsorption on the Pt3Sn(1 1 1) surface

Exposure of the Pt3Sn(1 1 1) surface to oxygen at a pressure in the 10-6 mbar range at 800 K leads to the formation of a chemisorbed phase with a (4 × 4) periodicity. In previous works we investigated the structure of the (4 × 4) phase by means of scanning tunneling microscopy (STM) and XPD. STM images show that the (4 × 4) periodicity results from an array of protrusions and holes. XPD data suggest that oxygen adsorption induces the reconstruction of the substrate with the formation of a Sn-O overlayer. In the present work, several structural models compatible with the STM and XPD results were tested by tensor LEED analysis. The best agreement with the experimental I-V curves was obtained for a model similar to that proposed to interpret the STM images of the Ag(1 1 1)(4 × 4)-O phase. According to this structure, the protrusions observed in STM would correspond to tin atoms occupying on-top positions

Seismic hazard in the Po Plain and the 2012 Emilia earthquakes

The Emilia earthquakes of May 20, 2012 (ML 5.9, INGV; MW 6.11, http://www.bo.ingv.it/RCMT/) and May 29, 2012 (ML 5.8, INGV; MW 5.96, http://www.bo.ingv.it/RCMT/) struck an area that in the national reference seismic hazard model [MPS04; http://zonesismiche.mi.ingv.it, and Stucchi et al. 2011] is characterized by expected horizontal peak ground acceleration (PGA) with a 10% probability of exceedance in 50 years that ranges between 0.10 g and 0.15 g (Figure 1), which is a medium level of seismic hazard in Italy. The strong impact of the earthquakes on a region that is not included among the most hazardous areas of Italy, and the ground motion data recorded by accelerometric networks, have given the impression to the population and the media that the current seismic hazard map is not correct, and thus needs to be updated. Since the MPS04 seismic hazard model was adopted by the current Italian building code [Norme Tecniche per le Costruzioni 2008, hereafter termed NTC08; http://www.cslp. it/cslp/] as the basis to define seismic action (the design spectra), any modification to the seismic hazard model would also affect the building code. The aim of this paper is to briefly present the data that support the seismic hazard model in the area, and to perform some comparisons between recorded ground motion with seismic hazard estimates and design spectra. All of the comparisons presented in this study are for the horizontal components only, as the Italian hazard model did not perform any estimates for the vertical component