MetaEvent Web-Service
The MetaEvent database of Seismic Source Parameters collects and disseminates through this web-service seismic source parameters related to earthquakes in Italy. The core data include parameters such as moment magnitude (MW), seismic moment (M0), and radiated energy (ER), corner frequency (fc) and between-event terms (δBe) derived from various types of analyses, encompassing automatic methods for real-time or near real-time estimation of source parameters and offline analyses.
The MetaEvent Database and Web-Service were designed and implemented under the framework of the PNRR-MEET project.
Project Coordinator: Spallarossa D. (Unige, daniele.spallarossa@unige.it)
Data Managers: Spallarossa D. (Unige, activity coordinator), Morasca P. (INGV, activity coordinator), Sgobba S. (INGV), Lanzano G. (INGV), Pacor F. (INGV), Saraò A. (OGS, activity coordinator); Moratto L. (OGS); Costa G. (UniTS, activity coordinator), Fornasari F. (UniTS)
Database and Web Service Managers: Felicetta C. (INGV), Scafidi D. (Unige), Russo E. (INGV)
A complete list of supported options and usage examples of the MetaEvent Web-Service is available in the query-options webpage.
Available URLs
Feature Notes
- The output is provided in GEOJSON format
- Brief description of the analysis:
CCT analysis: Coda Calibration Technique (CCT) uses seismic coda waves to model site and path effects, ensuring stable source spectra across magnitudes and distances (Morasca et al., 2022). In calibrated regions, CCT can generate envelopes, define coda windows, apply the model, and export measurements with uncertainties for future events.
GIT analysis: Generalized Inversion Technique (GIT) separates source, path, and site effects from seismic spectra using non-parametric, least-squares inversion without predefined models. The results are interpreted with standard seismological models and can be applied to future events in the same region (Morasca et al., 2023)
RAMONES analysis: as part of the RAMONES project (Rapid Assessment of MOmeNt and Energy Service, Spallarossa et el., 2021), this techniques have been calibrated to estimate the seismic moment (M0) and radiated energy (ER) from waveform-derived parameters. Specifically, M0 is estimated from the peak displacement (PD), while ER is derived from the integral of the squared velocity (IV2). In regions where these relationships have been calibrated, M0 and ER can be rapidly estimated for future earthquakes.
RESIDUAL analysis: the median event residual or between-event term represents the systematic error in predicting the seismic motion of an event using a reference ground motion model (GMM). It is obtained by decomposing the residuals (logarithmic difference between observation and prediction), removing all the other systematic effects and the aleatory resulting component (Al-Atik et al., 2010). For the MetaEvent database, the residuals (δBe) and the associated aleatory variabilities (τe) are computed between the ordinates of the horizontal and vertical Fourier amplitude spectrum of the ITACAext 2.0 dataset (Lanzano et al., 2024; Lanzano et al., 2025) with respect to the reference GMM (Lanzano et al., 2022).
RT analysis: the seismic moment (M0) and corner frequency (fc) are computed in near-real time from the velocity and displacement spectra (Gallo et al., 2014) and then used to compute the moment magnitude (MW) and equivalent source radius, respectively. Brune’s model of the source, defined upon the M0 and fc estimates, is used to estimate the radiated seismic energy which, in turn, is introduced in the computation of the energy magnitude (Me). The apparent stress drop is derived from the ratio of radiated energy and M0. By computing these parameters station-wise, it is possible to estimate the network mean and standard deviation associated to each quantity for each event.
SA analysis: the MW is estimated from response spectra (SA) computed at selected periods (0.3 s and 1.0 s), using empirical relationships specifically calibrated for Northeastern Italy. These relationships have been developed and validated in previous studies (Moratto et al., 2017; Tarchini et al., 2025).
SS analysis: SourceSpec (SS) method computes seismic source parameters by inverting the P- or S-wave displacement amplitude spectra recorded at each station. The SourceSpec algorithm (Satriano 2024) is utilized in Northeastern Italy to derive the source parameters, using the ω-2 Brune's source spectrum model (Moratto et al., 2026).
- Basic metadata such as magnitude and origin are provided from INGV FDSN event web-service
How to cite
Source Parameters Working Group (2025). MetaEvent database of Seismic Source Parameters. Istituto Nazionale di Geofisica e Vulcanologia (INGV). DOI 10.13127/metaevent
References
- Al‐Atik L., Abrahamson N.A., Bommer J.J., Scherbaum F., Cotton F., Kuehn N. (2010) The variability of ground‐motion prediction models and its components, Seismol. Res. Lett. 81, no. 5, 794–801.
- Gallo A., Costa G., Suhadolc P. (2014). Near real-time automatic moment magnitude estimation. Bull Earthquake Eng 12, 185–202. DOI: 10.1007/s10518-013-9565-x
- Lanzano G., Felicetta C., Pacor F., Spallarossa S., Traversa P. (2022) Generic‐To‐Reference Rock Scaling Factors for Seismic Ground Motion in Italy. Bulletin of the Seismological Society of America 2022;; 112 (3): 1583–1606. DOI: 10.1785/0120210063
- Lanzano G., Vitrano L., Felicetta C., Russo E., D Amico M., Mascandola C., Sgobba S., Brunelli G., Ramadan F., Pacor F., Luzi L. (2024) ITACAext flatfiles: parametric tables of metadata and strong motion intensity measures. Istituto Nazionale di Geofisica e Vulcanologia (INGV). DOI: 10.13127/itaca.4.0/itacaext_flatfile.2.0
- Morasca P., Bindi D., Mayeda K., Roman-Nieves J., Barno J., Walter W. R., Spallarossa D. (2022). Source scaling comparison and validation in central Italy: Data intensive direct s waves versus the sparse data coda envelope methodology. Geophysical Journal International, 231(3), 1573-1590.
- Morasca P., D Amico M., Sgobba S., Lanzano G., Colavitti L., Pacor F., Spallarossa D. (2023). Empirical correlations between an FAS non-ergodic ground motion model and a GIT derived model for Central Italy. Geophysical Journal International, 233(1), 51-68.
- Moratto L., Abdi F., Saraò A. (2026). Seismic source parameters analysis in Southeastern Alps and associated tectonic implications. Tectonophysics 923, 231069. DOI: 10.1016/j.tecto.2026.231069
- Moratto L., Saraò A., Priolo E. (2017) Moment Magnitude (MW) Estimation of Weak Seismicity in Northeastern Italy. Seismological Research Letters 2017; 88 (6): 1455–1464. DOI: 10.1785/0220170063
- Satriano, C. (2022). SourceSpec – Earthquake source parameters from P- or S-wave displacement spectra (v1.6). DOI: 10.5281/zenodo.6954238
- Spallarossa D., Picozzi M., Scafidi D., Morasca P., Turino C., Bindi D. (2021) The RAMONES Service for Rapid Assessment of Seismic Moment and Radiated Energy in Central Italy: Concepts, Capabilities, and Future Perspectives. Seismological Research Letters; 92 (3): 1759–1772. DOI: 10.1785/0220200348
- Tarchini G., Moratto L., Saraò A. (2025). A comprehensive moment magnitude catalog for the Northeastern Italy region. Seismological Research Letters. DOI: 10.1785/0220240303
License
The MetaEvent data is licensed under the terms of the "Creative Commons Attribution 4.0 International (CC BY 4.0)" License. This means that you are free to share (reproduce, distribute, communicate to the public, publicly display, perform and play this material in any medium and format) and adapt (remix and build upon the material for any purpose, even commercially). The licensor cannot revoke these freedoms as long as you follow the license terms. You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
Backend Python software used by this web service was developed and maintained by Felicetta C.
