The moment duration scaling relation for slow rupture arises from transient rupture speeds

This is a Preprint and has not been peer reviewed.

Downloads

Download Preprint

Authors

Kjetil Thøgersen , Henrik Andersen Sveinsson, Julien Scheibert, Francois Renard, Anders Malthe-Sørenssen

Abstract

The relation between seismic moment and earthquake duration for slow rupture follows a different power law exponent than sub-shear rupture. The origin of this difference in exponents remains unclear.
Here, we introduce a minimal one-dimensional Burridge-Knopoff model which contains slow, sub-shear and super-shear rupture, and demonstrate that different power law exponents occur because the rupture speed of slow events contains long-lived transients. Our findings suggest that there exists a continuum of slip modes between the slow and fast slip end-members, but that the natural selection of stress on faults can cause less frequent events in the intermediate range. We find that slow events on one-dimenional faults follow $\bar{M}_{0,\text{slow,1D}}\propto\bar{T}^{0.63}$ with transition to $\bar{M}_{0,\text{slow,1D}}\propto\bar{T}^\frac{3}{2}$ for longer systems or larger prestress, while the sub-shear events follow $\bar{M}_{0,\text{sub-shear},1D}\propto\bar{T}^2$. The model also predicts a super-shear scaling relation $\bar{M}_{0,\text{super-shear,1D}}\propto\bar{T}^3$. Under the assumption of radial symmetry, the generalization to two-dimensional fault planes compares well with observations.

DOI

https://doi.org/10.31223/osf.io/jnvtr

Subjects

Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics

Keywords

Dates

Published: 2019-07-16 19:38

Last Updated: 2019-09-05 08:14

Older Versions
License

GNU Lesser General Public License (LGPL) 2.1

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.