Relative afterslip moment does not correlate with aftershock productivity: implications for the relationship between afterslip and aftershocks

Churchill, R. M., Werner, M. J., Biggs, J. and Fagereng, Ake ORCID: https://orcid.org/0000-0001-6335-8534 2022. Relative afterslip moment does not correlate with aftershock productivity: implications for the relationship between afterslip and aftershocks. Geophysical Research Letters 49 (24) , e2022GL101165. 10.1029/2022gl101165

PDF - Published Version Available under License Creative Commons Attribution. Download (1MB)

Abstract

Aseismic afterslip has been proposed to drive aftershock sequences. Both afterslip moment and aftershock number broadly increase with mainshock size, but can vary beyond this scaling. We examine whether relative afterslip moment (afterslip moment/mainshock moment) correlates with several key aftershock sequence characteristics, including aftershock number and cumulative moment (both absolute and relative to mainshock size), seismicity rate change, b‐value, and Omori decay exponent. We select M w ≥ 4.5 aftershocks for 41 tectonically varied mainshocks with available afterslip models. Against expectation, relative afterslip moment does not correlate with tested aftershock characteristics or background seismicity rate. Furthermore, adding afterslip moment to mainshock moment does not improve predictions of aftershock number. Our findings place useful empirical constraints on the link between afterslip and potentially damaging M w ≥ 4.5 aftershocks and raise questions regarding the role afterslip plays in aftershock generation.

Item Type:	Article
Date Type:	Published Online
Status:	Published
Schools:	Earth and Environmental Sciences
Additional Information:	License information from Publisher: LICENSE 1: URL: http://creativecommons.org/licenses/by/4.0/
Publisher:	Wiley
ISSN:	0094-8276
Date of First Compliant Deposit:	3 January 2023
Date of Acceptance:	15 December 2022
Last Modified:	09 May 2023 08:29
URI:	https://orca.cardiff.ac.uk/id/eprint/155326

Actions (repository staff only)

Edit Item