TY - JOUR
T1 - Probabilistic seismic hazard analysis in low-seismicity regions
T2 - An investigation of sensitivity with a focus on Finland
AU - Fülöp, Ludovic
AU - Mäntyniemi, Päivi
AU - Malm, Marianne
AU - Toro, Gabriel
AU - Crespo, María J.
AU - Schmitt, Timo
AU - Burck, Simon
AU - Välikangas, Pekka
N1 - Funding Information:
The nuclear licensees Fortum Power and Heat Oy, Teollisuuden Voima Oyj, and Fennovoima Oy are acknowledged for their sponsorship of the SENSEI project and for providing documentation of their preexisting PSHA studies. STUK is acknowledged for contributing both financially and by providing the logistic framework for the project. The project meetings were forums of fruitful discussions and provided the fundaments for carrying out this work. Thanks to Kati Oinonen from the Institute of Seismology, University of Helsinki, for preparing Figure . Thanks to Cathryn Primrose-Mathisen who provided professional English language assistance during the preparation of this article. She was not responsible for reviewing the final version. Three anonymous reviewers are thanked for their thorough review and constructive suggestions that significantly improved the original manuscript. Editor-in-Chief John J. Clague is thanked for his assistance.
Publisher Copyright:
© 2022, The Author(s).
PY - 2023/3
Y1 - 2023/3
N2 - We investigate probabilistic seismic hazard analysis (PSHA) in low-seismicity regions in which epistemic uncertainties are largely due to the sparsity of data, with a focus on Finland, northern Europe. We investigate the sensitivity of site-specific PSHA outcomes to different choices of basic input parameters, starting from preexisting PSHA models of the nuclear licensees in the country, without producing a final hazard curve. The outcome shows that the parameters and models needed to estimate future seismicity rates from actual observations, in particular the b value, seismicity rates, and the largest possible magnitude, Mmax, as well as the median ground-motion prediction equation, play significant roles. The sensitivity also depends on the spectral frequency; for example, the effect of Mmax is significant especially for a low-frequency hazard at annual frequency of exceedance 10−5 but more moderate for peak ground acceleration. The delineation of seismic source zones (SSZs) remains ambiguous in regions of low seismicity. This, combined with the dominance of the host SSZ and its seismicity parameters, may have a substantial impact on the outcome. Our results are quantitatively applicable to Finland, but may also be of relevance to other low-seismicity regions in Europe and elsewhere. For future work we recommend the exploration of PSHA sensitivity with focus on the host SSZ with its immediate vicinity and the b value around the site of interest.
AB - We investigate probabilistic seismic hazard analysis (PSHA) in low-seismicity regions in which epistemic uncertainties are largely due to the sparsity of data, with a focus on Finland, northern Europe. We investigate the sensitivity of site-specific PSHA outcomes to different choices of basic input parameters, starting from preexisting PSHA models of the nuclear licensees in the country, without producing a final hazard curve. The outcome shows that the parameters and models needed to estimate future seismicity rates from actual observations, in particular the b value, seismicity rates, and the largest possible magnitude, Mmax, as well as the median ground-motion prediction equation, play significant roles. The sensitivity also depends on the spectral frequency; for example, the effect of Mmax is significant especially for a low-frequency hazard at annual frequency of exceedance 10−5 but more moderate for peak ground acceleration. The delineation of seismic source zones (SSZs) remains ambiguous in regions of low seismicity. This, combined with the dominance of the host SSZ and its seismicity parameters, may have a substantial impact on the outcome. Our results are quantitatively applicable to Finland, but may also be of relevance to other low-seismicity regions in Europe and elsewhere. For future work we recommend the exploration of PSHA sensitivity with focus on the host SSZ with its immediate vicinity and the b value around the site of interest.
KW - Finland
KW - Low-seismicity regions
KW - Nuclear power plant
KW - Probabilistic seismic hazard analysis
KW - Sensitivity investigation
UR - http://www.scopus.com/inward/record.url?scp=85140221994&partnerID=8YFLogxK
U2 - 10.1007/s11069-022-05666-4
DO - 10.1007/s11069-022-05666-4
M3 - Article
AN - SCOPUS:85140221994
SN - 0921-030X
VL - 116
SP - 111
EP - 132
JO - Natural Hazards
JF - Natural Hazards
IS - 1
ER -
