Strong evidence for non‐similar earthquake source scaling in central Italy

Abstract

The scaling of earthquakes of the Central Apennines (Italy) is investigated using broadband seismograms from the Colfiorito sequence (4 ≤ M W ≤ 6). Our results are not consistent with self‐similar scaling, and can be described by the following relationship: M 0 ∝ f c −(3 + ɛ) , where ɛ = 1.7 ± 0.3. We speculate that dynamic fault lubrication by fluid pressurization may be responsible for such extreme behavior, and use our results for the calibration of a weak‐motion‐based predictive relationship for the ground motion ( M W ≤ 4.1) up to M W ∼ 6 for this region.