Abstract
This final peer-reviewed version of this paper has now been published in Geomechanics and Geophysics for Geo-energy and Geo-resources.
DOI: 10.1007/s40948-024-00895-2
A key element in the assessment of seismic hazard is estimation of the maximum possible earthquake magnitude, Mmax. A great deal of effort has been invested in developing approaches to estimate Mmax for natural (tectonic) earthquakes, especially in regions of relatively low seismicity where it is difficult to associate observed seismicity with known geological faults. In probabilistic seismic hazard analysis, which has become the almost ubiquitous global standard, it is generally found that Mmax exerts at most a very modest influence on the results. This might be part of the reason that rather large values of Mmax are often assigned to seismic source zones, even where there is no evidence for geological structures capable of generating such large earthquakes. For induced seismicity, however, Mmax estimates can have far-reaching implications, both in terms of quantitative assessments of the resulting seismic hazard and risk, and in terms of the public and regulatory perception of this risk. Estimates of Mmax for induced seismicity need to distinguish between driven earthquakes, for which magnitudes are largely controlled by operational parameters, and triggered tectonic earthquakes-and be accompanied by estimates of the likelihood of such triggering. Distributions of Mmax may be limited to smaller magnitudes than distributions for natural seismicity due to the shallow depth of most injection/extraction wells. Mmax estimates for induced seismicity will also be influenced by any traffic light scheme in operation.
