Reply to “Comment on ‘Total Probability Theorem Versus Shakeability: A Comparison between Two Seismic‐Hazard Approaches Used in Central Asia’ by D. Bindi and S. Parolai” by A. A. Gusev

Abstract

The authors would like to thank Gusev (2016; hereafter referred to as Gu16) for his interest in our work (Bindi and Parolai, 2015; hereafter referred to as BP15) and for providing additional information about the methodology followed to prepare the hazard map for northern Eurasia included in the Global Seismic Hazard Assessment Program (GSHAP) model (Ulomov and the GSHAP region 7 Working Group, 1999, hereafter referred to as Ul99; Zhang et al. , 1999). The main interest of BP15 was to compare two probabilistic seismic‐hazard analysis approaches, namely the Riznichenko (1965) and the Cornell (1968, 1971) methods, which differ in the way they account for the aleatoric uncertainty. Although Gu16 agrees with the main conclusions of BP15 (“Another possible cause of the discussed discrepancy is certain difference between hazard calculation procedures of Riznichenko and Cornell. Both these observations of BP15 seem to be relevant, and need not be commented.”), he raises some criticisms against the discussions developed in BP15 regarding the GSHAP overestimation of the hazard level in central Asia (“Both assertments of BP15: that Ul99 hazard estimates are substantially exaggerated, and that this alleged fact is related to the use of Riznichenko (1965) procedures are incorrect.”). Here, it is worth remembering that, first, the overestimation of the Ul99 results is not an original statement of BP15, but, as also mentioned by Gu16, it was originally observed by Zhang et al. (1999) when compiling the GSHAP map, and, second, the Riznichenko approach followed in preparing the hazard map for northern Eurasia was a working hypothesis tested in BP15, not an absolute statement. Indeed, this hypothesis was inspired directly by Ul99 (“We calculate seismic hazard using an algorithm and software code designed by Gusev, Pavlov and Shumilina, following the principles of Riznichenko (1965) and Cornell (1968).”). Considering …