- Open Access
Transport-healing scaling for Omori exponents: A minimal model and its limits
APS Open Sci. 1, 000150 – Published 24 September, 2026
DOI: https://doi.org/10.1103/fgw2-2sxn
Abstract
The temporal decay of triggered seismicity is commonly described by the Omori law . I introduce a minimal phenomenological framework that relates this temporal decay to two concurrent processes: the spatial spreading of a triggering perturbation and the progressive depletion of elements that remain susceptible to failure. The model yields the scaling relation , where characterizes spreading, is an effective spatial dimension, and describes depletion or healing. This relation provides a joint consistency test rather than a unique inversion of the Omori exponent for material healing. Numerical simulations recover the predicted scaling. A comparison with published earthquake-pair statistics illustrates that slow spatial spreading can be identified, but also that spatial and temporal exponents cannot be combined unless their underlying observables and event selections are compatible. The main implication is that the Omori exponent alone cannot generally be interpreted as a direct measure of fault or reservoir healing; testing the proposed relation requires compatible estimates of spatial spreading, event-rate decay, effective geometry, and, where possible, an independent recovery observable.
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