Jouve B. D., Marsan D., Socquet A., Beauval Céline. (2024). Assessing the adequacy of earthquake catalog sampling for long-term seismicity in low-to-moderate seismic regions : a geodetic perspective. Seismological Research Letters, 95 (6), 3494-3506. ISSN 0895-0695.
Titre du document
Assessing the adequacy of earthquake catalog sampling for long-term seismicity in low-to-moderate seismic regions : a geodetic perspective
Jouve B. D., Marsan D., Socquet A., Beauval Céline
Source
Seismological Research Letters, 2024,
95 (6), 3494-3506 ISSN 0895-0695
Seismic hazard assessment in low-to-moderate seismicity regions can benefit from theknowledge of surface deformation rates to better constrain earthquake recurrence mod-els. This, however, amounts to assuming that the known seismicity rate, generallyobserved over historical times (i.e., up to a few centuries in Europe), provides a represen-tative sample of the underlying long-term activity. We here investigate how this limitedsampling can affect the estimated seismic hazard and whether it can explain the disagree-ment between the seismic moment loading rate as seen by nowadays Global NavigationSatellite Systems (GNSS) measurements and the seismic moment release rate by pastearthquakes, as is sometimes observed in regions with limited activity. We approach thisissue by running simulations of earthquake time series over very long timescales thataccount for temporal clustering and the known magnitude-frequency distribution in suchregions, and that those are constrained to a seismic moment rate balance between geo-detic and seismicity estimates at very long timescales. We show that, in the example ofsoutheastern Switzerland, taken here as a case study, this sampling issue can indeedexplain this disagreement, although it is likely that other phenomena, including aseismicdeformation and changes in strain rate due to erosional and/or glacial rebound, may alsoplay a significant role in this mismatch
