Modeled and observed magnitude-frequency distribution, Oklahoma-Kansas potential induced earthquake catalog, 2016-2017

The b-value for the earthquake catalog from the Oklahoma-Kansas potentially induced earthquake zone is computed with the maximum likelihood method (MLE) (Aki, 1965). We use the minimum magnitude of completeness that is used for the seismicity rate models (Mc=2.7) and the earthquakes from 2016 and 2017 and find b=1.5 (1.48+/-0.05). However, we find that the b-value from the full (non-declustered) catalog is sensitive to the minimum magnitude of completeness, perhaps due to the moment magnitudes at these values being highly dependent on the conversion relations and the measurements of local magnitudes. Aki, K. (1965). Maximum likelihood estimate of b in the formula log N= a-bM and its confidence limits. Bull. Earthq. Res. Inst., Tokyo [...]