Enhanced Seismicity Monitoring in the Rapid Scientific Response to the 2025 Santorini Crisis - Earthquake Catalogues

This dataset accompanies the article: Segou, M., Dervisi, F., Tan, X., Choudhary, R., Martínez-Garzón, P., Scotto di Uccio, F., Beroza, G., Giacomuzzi, G., Chiarabba, C., Shelley, W., Prejean, S., Pesicek, J., Wellik, J. J., Bohnhoff, M., Pyle, D., Synolakis, C., Parsons, T., Ganas, A., Ellsworth, W., Baptie, B., Festa, G., Poli, P., and Marzocchi, W., “Enhanced Seismicity Monitoring in the Rapid Scientific Response to the 2025 Santorini Crisis” We provide three seismicity catalogues for the Santorini region covering the 2025 crisis: an initial DL catalogue generated via QuakeFlow, an enhanced DL catalogue extended by template matching, and a relocated catalogue. DL catalogue (DL_catalogue_Santorini_2025.csv): This catalogue was generated with the QuakeFlow deep learning workflow, which uses PhaseNet for phase picking and GaMMA for event association. event_index Unique event identifier time Event time (UTC) magnitude Event magnitude longitude Event longitude latitude Event latitude depth_km Event depth (km) sigma_time Standard deviation of phase time residuals (s) sigma_amp Standard deviation of amplitude residuals (in log scale) cov_time_amp Covariance between phase time and amplitude residuals gamma_score Sum of the posterior probabilities of all picks associated with the event (indicates association confidence) Enhanced DL catalogue (enhanced_DL_catalogue_Santorini_2025.csv): This catalogue was produced with the EQCorrscan template matching technique using the initial deep learning detections as templates to scan continuous waveforms. Locations and magnitudes are assigned to newly detected events based on their cross-correlation similarity and amplitude ratios relative to the template events. time Event time (UTC) ml Local magnitude ml_est_type Local magnitude estimation type (AR or GAMMA)* latitude Event latitude** longitude Event longitude** depth_km Event depth (km)** * For events detected by QuakeFlow, the magnitude was taken from the DL catalogue (GAMMA). For new events detected by template matching, the magnitude was derived through amplitude ratio with the most similar template (AR). ** For new events introduced by template matching, the location attributed is that of the most similar template. Relocated catalogue (relocated_catalogue_Santorini_2025.csv): This is the relocated catalogue that was created using TomoDD, incorporating a 1D velocity model inverted with VELEST. ID Unique event identifier LAT Relocated latitude (decimal degrees) LON Relocated longitude (decimal degrees) DEPTH Relocated depth (km) X East-west location (m) relative to cluster centroid Y North-south location (m) relative to cluster centroid Z Depth location (m) relative to cluster centroid EX East-west error (m) EY North-south error (m) EZ Depth error (m) NCCP Number of cross-correlated P-wave data NCCS Number of cross-correlated S-wave data NCTP Number of catalogue P-wave data NCTS Number of catalogue S-wave data RCC RMS residual for cross-correlated data RCT RMS residual for catalogue data time Event time (UTC) x(km) 2D Euclidean coordinate (Easting) based on (25.50E, 36.50N) y(km) 2D Euclidean coordinate (Northing) based on (25.50E, 36.50N) year_noa Year from NOA catalogue month_noa Month from NOA catalogue date_noa Date from NOA catalogue hour_noa Hour from NOA catalogue min_noa Minute from NOA catalogue sec_noa Second from NOA catalogue lat_noa Latitude from NOA catalogue lon_noa Longitude from NOA catalogue depth_noa Depth from NOA catalogue ml_noa Local magnitude from NOA catalogue x(km)_noa 2D Euclidean coordinate (Easting) based on (25.50E, 36.50N) from NOA catalogue y(km)_noa 2D Euclidean coordinate (Northing) based on (25.50E, 36.50N) from NOA catalogue ml Calculated local magnitude fi Calculated Frequency Index Further information can be found in the user guide of HypoDD (pages 21-22): https://www.ldeo.columbia.edu/~felixw/hypoDD.html NCCP, NCCS, NCTP and NCTS can be used for quality control. Higher values (any individual, especially NCCP and NCCS, or the sum of four ($\geq 200$)) indicate a good constraint of the location. Event info from NOA catalogue is provided if an earthquake could be associated with one from NOA catalogue based on a $\pm 1.5s$ time criterion.