Nonlinear site response evidence of K-NET and KiK-net records from the 2011 off the Pacific coast of Tohoku Earthquake - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Earth Planets and Space Year : 2011

Nonlinear site response evidence of K-NET and KiK-net records from the 2011 off the Pacific coast of Tohoku Earthquake

Abstract

We analyzed the acceleration time histories recorded by the K-NET and KiK-net stations of the Mw 9 Tohoku Earthquake in order to investigate site response issues related to near-source effects. Time-frequency analysis of K-NET stations in the Miyagi prefecture, closest to the rupture area, show that sites having a Vs30 < 400 m/s present a combination of deamplification at frequencies higher than 5 to 10 Hz and cyclic mobility (high acceleration peaks riding over a low frequency carrier). This suggests strong nonlinear site response at these stations. Furthermore, using KiK-net data we are able to compute borehole transfer functions from the mainshock and events having small PGA values from the local dataset. The ratio between weak-motion and strong-motion borehole transfer functions constitutes an indicator of nonlinear site response. This ratio reveals strong dependence on Vs30 and shows that widespread nonlinear behavior took place during this large earthquake.

Domains

Geomorphology
Fichier principal
Vignette du fichier
Bonilla2011_Article_NonlinearSiteResponseEvidenceO.pdf (1.64 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-00679354 , version 1 (28-11-2021)

Licence

Attribution - NonCommercial - NoDerivatives

Identifiers

Cite

Luis Fabian Bonilla, Kenichi Tsuda, Nelson Pulido, Julie Regnier, Aurore Laurendeau. Nonlinear site response evidence of K-NET and KiK-net records from the 2011 off the Pacific coast of Tohoku Earthquake. Earth Planets and Space, 2011, 63 (7), pp.785-789. ⟨10.5047/eps.2011.06.012⟩. ⟨insu-00679354⟩
195 View
60 Download

Altmetric

Share

Gmail Facebook X LinkedIn More