| 11 May 2026
A workflow for the identification of earthquake sources from macroseismic data
Abstract. Macroseismic intensity data are a fundamental source of information for characterising historical earthquakes. This study presents a methodology to constrain the sources of large earthquake through the analysis and modelling of macroseismic intensity data. The proposed workflow consists of three main stages: (1) the identification and removal of outlier intensity data points; (2) the revision of macroseismic earthquake parameters (epicentral location and magnitude); and (3) the construction of three-dimensional (3D) seismogenic sources, simulation of ground shaking including site effects, and a subsequent residual analysis. The application of this workflow to a set of case studies from the parametric catalogue of Italian earthquakes demonstrates that the implemented approach allows the identification of seismogenic sources for large to moderate magnitude events, which are consistent with macroseismic data, geological structures and ground motion data, when available. The results of this study can have direct implications for seismic hazard assessment and shaking scenario modelling. The proposed workflow can be systematically applied to reconstruct the seismogenic sources of the strongest Italian historical earthquakes (Mw ≥ 5.5).
Title: A workflow for the identification of earthquake sources from macroseismic data by Gironelli et al.
The manuscript presents a well-structured and scientifically valuable workflow for reconstructing seismogenic sources using macroseismic intensity data. The integration of pre-processing, source reconstruction, ground-motion simulation, and residual analysis is comprehensive and methodologically sound. The topic is highly relevant for historical seismology and seismic hazard assessment, especially in regions with limited instrumental data but abundant macroseismic observations. The workflow is clearly explained and supported by suitable case studies, including both instrumental and historical earthquakes, thereby strengthening the applicability of the proposed methodology. The manuscript demonstrates a strong use of Italian seismic databases, such as DBMI15, CPTI15, DISS, and ITACA, and effectively integrates multidisciplinary datasets.
- in abstract change “This study presents a methodology to constrain the sources of large earthquakes...”
Additionally, please mention the novelty of integrating residual analysis with outlier detection in the abstract.
- The literature review is extensive; however, it may benefit from a short paragraph emphasizing the limitations of existing approaches and how the proposed workflow addresses them.
-Some long sentences could be simplified for better readability, particularly lines 50–65.
- The explanation of the pre-processing stage and outlier removal using the Gomez-Capera et al. (2024) IPE is scientifically sound.
- The authors may consider discussing the sensitivity of the results to the selected 3σ threshold for outlier identification.
- The methodology would benefit from a small flowchart legend explaining abbreviations such as BE, RMSE, GOM20, and OLI22 for readers unfamiliar with the terminology.
- The choice of Wells and Coppersmith (1994) scaling relations is appropriate, but the limitations of applying these empirical relations to historical earthquakes could be briefly discussed.
- The discussion of the 1990 Potenza earthquake clearly illustrates how outliers can bias epicentral estimation.
- In Tables 3 and 5, it may help readers if the best-performing source configurations are highlighted using bold formatting in addition to the asterisk.
- Some figure captions are very long and may be shortened for improved readability.
- Increase font size in several figures (especially residual maps and legends), as some labels are difficult to read.
- Table formatting could be improved slightly for better alignment of columns and readability.
Corrections
“large earthquake” → “large earthquakes”
“best fits the data is identified” → “best-fitting fault is identified”
“ground shaking including the site effects” → “ground shaking including site effects”