Journal
EARTH PLANETS AND SPACE
Volume 63, Issue 7, Pages 785-789Publisher
TERRA SCIENTIFIC PUBL CO
DOI: 10.5047/eps.2011.06.012
Keywords
Site response; cyclic mobility; Tohoku Earthquake; K-NET; KiK-net
Categories
Ask authors/readers for more resources
We analyzed the acceleration time histories recorded by the K-NET and KiK-net stations of the M(w) 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 V(s30) < 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 V(s30) and shows that widespread nonlinear behavior took place during this large earthquake.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available