Year: 2025
Type: article
Abstract: A compilation of many data sets indicates that the exponents for the cumulative length distribution of small faults of L < T, the brittle thickness, and for large faults of L > T, are both approximately 2. The same result was found by Zou and Fialko (2024), but that was fortuitous: their finding being contingent on two cancelling errors. If is 2 for both distributions, it indicates that the exponent B of the cumulative moment distribution is 2/3 for small faults and 1 for large faults, the same values as found for small and large earthquakes. The moment release rates obtained from both earthquake and fault data have also been found to correspond. This demonstrates that in continental regions the long-assumed correspondence between earthquakes and faults is exclusive. All tectonic earthquakes must occur on faults and faults must slip predominately in earthquakes. The relative contribution of small earthquakes/faults to strain is minor for a single large fault over the recurrence time of the fault-rupturing earthquake because that case is governed by the characteristic earthquake model. In contrast, over a larger region containing many moderate sized faults, for which the Gutenberg-Richter distribution holds, the relative contribution of small earthquakes/faults to strain may be significant. These different behaviors characterize mature smooth vs. immature segmented fault systems.
Source: Earth and Space Science
DOI: 10.1029/2025ea004217
Author: Christopher H. Scholz
Institutions: Lamont-Doherty Earth Observatory, Columbia University
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,650
OpenAlex ID: W4413264899