Reply to "Comment on 'Operational Earthquake Forecasting: Status of Knowledge and Guidelines for Implementation by Jordan et al. [2011]' by Stuart Crampin"

In his commentary on the International Commission on Earthquake Forecasting (ICEF) report [Jordan et al. 2011], Crampin [2012] claims that observable changes in shear-wave splitting can predict large earthquakes on short time scales with high reliability and skill, and he challenges a central ICEF finding—that no method has yet demonstrated such a predictive capability. In particular, Crampin asserts that "observations of seismic shear-wave splitting monitored at a three-borehole Stress-Monitoring Site (SMS) in central Italy could monitor stress-accumulation and stress-relaxation (crack-coalescence) before all damaging (M ≥ 5) earthquakes within 1000 km of the SMS […] This means that installation of one expensive SMS (preferably two throughout the length of Italy) would stress-forecast the time, magnitude, and in some circumstances fault-break of all potentially damaging on the mainland of Italy". Crampin's assertions are based on prediction methods he has advocated for several decades [e.g., Crampin et al. 1984; Crampin et al. 1990]. As part of the ICEF study, we reviewed the literature on these methods. Nothing contained in the present commentary compels us to alter our previous findings. [...]