Portugal earthquake dataset
87263 earthquakes in mainland Portugal, the Azores and Madeira from 1909-04-23 to 2026-11-11, including offshore areas.
Sources and methodology
IPMA, ISC Bulletin, EMSC, USGS.
Reports from different sources are matched within 30 seconds and 100 km. Before 1964, the thresholds are 60 seconds and 250 km. Origin time and epicentre use the first available source in the order IPMA, ISC, EMSC and USGS. Magnitude uses IPMA’s measurement when available, then moment magnitude (Mw), then the preferred source’s measurement.
Agencies revise their records. Before the 1960s, monitoring mainly captured large earthquakes. Many older records lack a magnitude and measurements use different scales. Counts depend on monitoring coverage.
Licence and attribution
The compilation is licensed under CC BY-NC 4.0. Non-commercial reuse requires attribution to the project and to the sources listed for each record. Each source’s terms also apply. Documentation and source terms.