Chapter 13 Bedrock structure around faults and its relation to earthquake disaster

Junpei Akamatsu, Keiichi Nishimura, Hitoshi Morikawa, Sumio Sawada, Kensuke Onoue, Hideo Saito, Mitsuru Jido, Takao Kagawa, Kazuo Kamura, Kenji Sato, Kunio Furuno, Masai Komazawa

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The frequency-wavenumber and horizontal-to-vertical ratio spectral analyses of microseisms (long-period microtremors), and the bandpass filtering of Bouguer gravity anomalies, were conducted to elucidate the subsurface structure around the eastern end of the severely damaged belt-like zone in the Kobe-Hanshin area which appeared during the 1995 Hyogokennanbu (Kobe) earthquake. A close relationship was found between the fault-related bedrock configuration thus obtained and the distribution of earthquake damage: a narrow zone of severe damage was located 1.5-2 km apart from the basin edge where the depth to bedrock changes abruptly by several hundreds to a thousand meters. The relationship was atributed to the amplification of ground motions due to the specific configuration of bedrock, that is, focusing of seismic waves and/or interference between incident S-waves and surface-waves secondarily generated at the basin edge. It is pointed out, as a lesson learned from the Hyogoken-nanbu earthquake disaster, that the investigation of fault-related 3-D bedrock configuration is an urgent issue for hazard mapping of an urban area on a sedimentary basin.

Original languageEnglish
Pages (from-to)199-216
Number of pages18
JournalDevelopments in Geotechnical Engineering
Volume81
Issue numberC
DOIs
Publication statusPublished - 1997
Externally publishedYes

Fingerprint

Disasters
disaster
Earthquakes
bedrock
earthquake
Wave interference
Seismic waves
Kobe earthquake 1995
microtremor
Surface waves
earthquake damage
Amplification
Hazards
Gravitation
gravity anomaly
basin
seismic wave
sedimentary basin
surface wave
ground motion

ASJC Scopus subject areas

  • Geotechnical Engineering and Engineering Geology

Cite this

Akamatsu, J., Nishimura, K., Morikawa, H., Sawada, S., Onoue, K., Saito, H., ... Komazawa, M. (1997). Chapter 13 Bedrock structure around faults and its relation to earthquake disaster. Developments in Geotechnical Engineering, 81(C), 199-216. https://doi.org/10.1016/S0165-1250(97)80014-4

Chapter 13 Bedrock structure around faults and its relation to earthquake disaster. / Akamatsu, Junpei; Nishimura, Keiichi; Morikawa, Hitoshi; Sawada, Sumio; Onoue, Kensuke; Saito, Hideo; Jido, Mitsuru; Kagawa, Takao; Kamura, Kazuo; Sato, Kenji; Furuno, Kunio; Komazawa, Masai.

In: Developments in Geotechnical Engineering, Vol. 81, No. C, 1997, p. 199-216.

Research output: Contribution to journalArticle

Akamatsu, J, Nishimura, K, Morikawa, H, Sawada, S, Onoue, K, Saito, H, Jido, M, Kagawa, T, Kamura, K, Sato, K, Furuno, K & Komazawa, M 1997, 'Chapter 13 Bedrock structure around faults and its relation to earthquake disaster', Developments in Geotechnical Engineering, vol. 81, no. C, pp. 199-216. https://doi.org/10.1016/S0165-1250(97)80014-4
Akamatsu, Junpei ; Nishimura, Keiichi ; Morikawa, Hitoshi ; Sawada, Sumio ; Onoue, Kensuke ; Saito, Hideo ; Jido, Mitsuru ; Kagawa, Takao ; Kamura, Kazuo ; Sato, Kenji ; Furuno, Kunio ; Komazawa, Masai. / Chapter 13 Bedrock structure around faults and its relation to earthquake disaster. In: Developments in Geotechnical Engineering. 1997 ; Vol. 81, No. C. pp. 199-216.
@article{c7c574909dd14a54a6b71440ef3e8caf,
title = "Chapter 13 Bedrock structure around faults and its relation to earthquake disaster",
abstract = "The frequency-wavenumber and horizontal-to-vertical ratio spectral analyses of microseisms (long-period microtremors), and the bandpass filtering of Bouguer gravity anomalies, were conducted to elucidate the subsurface structure around the eastern end of the severely damaged belt-like zone in the Kobe-Hanshin area which appeared during the 1995 Hyogokennanbu (Kobe) earthquake. A close relationship was found between the fault-related bedrock configuration thus obtained and the distribution of earthquake damage: a narrow zone of severe damage was located 1.5-2 km apart from the basin edge where the depth to bedrock changes abruptly by several hundreds to a thousand meters. The relationship was atributed to the amplification of ground motions due to the specific configuration of bedrock, that is, focusing of seismic waves and/or interference between incident S-waves and surface-waves secondarily generated at the basin edge. It is pointed out, as a lesson learned from the Hyogoken-nanbu earthquake disaster, that the investigation of fault-related 3-D bedrock configuration is an urgent issue for hazard mapping of an urban area on a sedimentary basin.",
author = "Junpei Akamatsu and Keiichi Nishimura and Hitoshi Morikawa and Sumio Sawada and Kensuke Onoue and Hideo Saito and Mitsuru Jido and Takao Kagawa and Kazuo Kamura and Kenji Sato and Kunio Furuno and Masai Komazawa",
year = "1997",
doi = "10.1016/S0165-1250(97)80014-4",
language = "English",
volume = "81",
pages = "199--216",
journal = "Developments in Geotechnical Engineering",
issn = "0165-1250",
publisher = "Elsevier",
number = "C",

}

TY - JOUR

T1 - Chapter 13 Bedrock structure around faults and its relation to earthquake disaster

AU - Akamatsu, Junpei

AU - Nishimura, Keiichi

AU - Morikawa, Hitoshi

AU - Sawada, Sumio

AU - Onoue, Kensuke

AU - Saito, Hideo

AU - Jido, Mitsuru

AU - Kagawa, Takao

AU - Kamura, Kazuo

AU - Sato, Kenji

AU - Furuno, Kunio

AU - Komazawa, Masai

PY - 1997

Y1 - 1997

N2 - The frequency-wavenumber and horizontal-to-vertical ratio spectral analyses of microseisms (long-period microtremors), and the bandpass filtering of Bouguer gravity anomalies, were conducted to elucidate the subsurface structure around the eastern end of the severely damaged belt-like zone in the Kobe-Hanshin area which appeared during the 1995 Hyogokennanbu (Kobe) earthquake. A close relationship was found between the fault-related bedrock configuration thus obtained and the distribution of earthquake damage: a narrow zone of severe damage was located 1.5-2 km apart from the basin edge where the depth to bedrock changes abruptly by several hundreds to a thousand meters. The relationship was atributed to the amplification of ground motions due to the specific configuration of bedrock, that is, focusing of seismic waves and/or interference between incident S-waves and surface-waves secondarily generated at the basin edge. It is pointed out, as a lesson learned from the Hyogoken-nanbu earthquake disaster, that the investigation of fault-related 3-D bedrock configuration is an urgent issue for hazard mapping of an urban area on a sedimentary basin.

AB - The frequency-wavenumber and horizontal-to-vertical ratio spectral analyses of microseisms (long-period microtremors), and the bandpass filtering of Bouguer gravity anomalies, were conducted to elucidate the subsurface structure around the eastern end of the severely damaged belt-like zone in the Kobe-Hanshin area which appeared during the 1995 Hyogokennanbu (Kobe) earthquake. A close relationship was found between the fault-related bedrock configuration thus obtained and the distribution of earthquake damage: a narrow zone of severe damage was located 1.5-2 km apart from the basin edge where the depth to bedrock changes abruptly by several hundreds to a thousand meters. The relationship was atributed to the amplification of ground motions due to the specific configuration of bedrock, that is, focusing of seismic waves and/or interference between incident S-waves and surface-waves secondarily generated at the basin edge. It is pointed out, as a lesson learned from the Hyogoken-nanbu earthquake disaster, that the investigation of fault-related 3-D bedrock configuration is an urgent issue for hazard mapping of an urban area on a sedimentary basin.

UR - http://www.scopus.com/inward/record.url?scp=77956774071&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77956774071&partnerID=8YFLogxK

U2 - 10.1016/S0165-1250(97)80014-4

DO - 10.1016/S0165-1250(97)80014-4

M3 - Article

AN - SCOPUS:77956774071

VL - 81

SP - 199

EP - 216

JO - Developments in Geotechnical Engineering

JF - Developments in Geotechnical Engineering

SN - 0165-1250

IS - C

ER -