Possibly because of interest or project links in RG, there appear nowdays many articles from the last few years of measurements of deformation modulus at dam sites, especially from Iran and Turkey. Most have parallel evaluations of the variability of the large number of empirical equations suggested, each evaluated over the range of recorded RMR89, GSI, Q-values, and occasional other measures, with the important comparison to actual plate load test results. In the case of Ajalloeian and Mohammadi, 2014 Estimation of limestone rock mass deformation modulus using empirical equations: recently in RG pages, it was good (from Q-system perspective) to see good correlation, also with the low modulus measurements, which seemed to be especially missed by RMR89 and GSI. But the question is why only one listed equation (Mitri, 1994, also Q-based) had depth H given as a variable? Always missed in these comparative modulus reviews is that the estimate based on Qc has been depth-dependent, as is Vp, since 1995. Besides the 1995 graph of depth-dependence, a simple equation given in Barton, 2007 (First Break) links Emass with Vp, Q and UCS, giving depth-dependent modulus, as used in Gjøvik cavern UDEC-BB modelling in 1994. The latter was stimulated by cross-hole tomography showing Vp increase with depth despite no improvement in Q or RQD with depth. There are other cases like this, and depth-dependence of cross-hole Vp with Q-logging down to > 1km is part of the data.

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