Rupture dynamics and ground motions from earthquakes in 2-D heterogeneous media

Samuel A. Bydlon, Eric M. Dunham

Research output: Contribution to journalArticlepeer-review

17 Scopus citations

Abstract

©2015. American Geophysical Union. All Rights Reserved. We perform 2-D simulations of earthquakes on rough faults in media with random heterogeneities (with von Karman distribution) to study the effects of geometric and material heterogeneity on the rupture process and resulting high-frequency ground motions in the near-fault region (out to ∼20km). Variations in slip and rupture velocity can arise from material heterogeneity alone but are dominantly controlled by fault roughness. Scattering effects become appreciable beyond ∼3km from the fault. Near-fault scattering extends the duration of incoherent, high-frequency ground motions and, at least in our 2-D simulations, elevates root-mean-square accelerations (i.e., Arias intensity) with negligible reduction in peak velocities. We also demonstrate that near-fault scattering typically occurs in the power law tail of the power spectral density function, quantified by the Hurst exponent and another parameter combining standard deviation and correlation length. Key Points Fault roughness, not material heterogeneity, dominates rupture process Introduce parameter that can be used to quantify near-fault scattering Scattering affects the duration and amplitude of high-frequency ground motions
Original languageEnglish (US)
Pages (from-to)1701-1709
Number of pages9
JournalGeophysical Research Letters
Volume42
Issue number6
DOIs
StatePublished - Mar 21 2015
Externally publishedYes

Fingerprint

Dive into the research topics of 'Rupture dynamics and ground motions from earthquakes in 2-D heterogeneous media'. Together they form a unique fingerprint.

Cite this