An eigenfrequency abacus for rapid estimation of block volumes from seismic noise measurements

Estimating the volume of rock masses is fundamental for the landslide characterization in areas prone to detachment, but it is challenging. The orientation and properties of discontinuities play a fundamental role. It has been shown that rock blocks’ volume could be underestimated if joints are erroneously assumed to be persistent, or overestimated if they are not fully detected. Unfortunately, in common practice, it is not easy to define the blocks’ volume because it is quite hard to estimate the actual shape and in particular the height of a block: non-open discontinuities, in fact, affect the portion of the block actually separated, influencing the height that has to be considered in the volume estimation.