Seismic evidence for reverse activation of a paleo-rifting system in the East Sea (Sea of Japan)

Hoseon Choi, Tae Kyung Hong, Xiaobo He, Chang Eob Baag

Research output: Contribution to journalArticle

35 Citations (Scopus)

Abstract

The Japanese Islands were separated from the Eurasian plate due to continental rifting during the Oligocene to mid-Miocene, which caused the opening of the East Sea (Sea of Japan). Such tectonic evolution in the East Sea is important for understanding the evolution of back-arc regions with active convergent margins. To understand the evolution of the paleo-rifted back-arc region, we investigate seismicity, crustal seismic anisotropy, focal mechanism solutions and ambient stress field around the Korean Peninsula. The Korean Peninsula displays diffused seismicity with small and moderate earthquakes. Shallow earthquakes rarely occur in the central East Sea. The crustal fast shear-wave polarization directions in the Korean Peninsula are observed to vary in azimuth between 40° and 90°. The focal mechanism solutions are calculated by long period waveform inversions. The ambient stress field is calculated from the focal mechanism solutions. The compressional stress field in the Korean Peninsula is observed to be in ENE-WSW, which is consistent with the fast shear-wave polarization directions. The compressional stress directions in the East Sea progressively change from ENE to SE with increasing longitude. The rapid change of compressional directions in the central East Sea prohibits accumulation of stress, causing rare shallow seismicity. High seismicity of reverse faulting events is observed at the fringes of the East Sea, in particular, around the east coast of the Korean Peninsula and the west coast of Japanese Islands, which correspond to paleo-rifted margins where compressional stresses are accumulated. The compressional stress field and active thrustal events suggest reverse activation of paleo-normal faults that were developed during the opening of the East Sea.

Original languageEnglish
Pages (from-to)123-133
Number of pages11
JournalTectonophysics
Volume572-573
DOIs
Publication statusPublished - 2012 Oct 17

Fingerprint

Sea of Japan
rifting
peninsulas
activation
stress distribution
stress field
seismicity
focal mechanism
coasts
S waves
margins
earthquakes
arcs
S-wave
polarization
earthquake
convergent margin
seismic anisotropy
longitude
sea

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Earth-Surface Processes

Cite this

Choi, Hoseon ; Hong, Tae Kyung ; He, Xiaobo ; Baag, Chang Eob. / Seismic evidence for reverse activation of a paleo-rifting system in the East Sea (Sea of Japan). In: Tectonophysics. 2012 ; Vol. 572-573. pp. 123-133.
@article{3bef175e588f4ceda8ccc5715149193c,
title = "Seismic evidence for reverse activation of a paleo-rifting system in the East Sea (Sea of Japan)",
abstract = "The Japanese Islands were separated from the Eurasian plate due to continental rifting during the Oligocene to mid-Miocene, which caused the opening of the East Sea (Sea of Japan). Such tectonic evolution in the East Sea is important for understanding the evolution of back-arc regions with active convergent margins. To understand the evolution of the paleo-rifted back-arc region, we investigate seismicity, crustal seismic anisotropy, focal mechanism solutions and ambient stress field around the Korean Peninsula. The Korean Peninsula displays diffused seismicity with small and moderate earthquakes. Shallow earthquakes rarely occur in the central East Sea. The crustal fast shear-wave polarization directions in the Korean Peninsula are observed to vary in azimuth between 40° and 90°. The focal mechanism solutions are calculated by long period waveform inversions. The ambient stress field is calculated from the focal mechanism solutions. The compressional stress field in the Korean Peninsula is observed to be in ENE-WSW, which is consistent with the fast shear-wave polarization directions. The compressional stress directions in the East Sea progressively change from ENE to SE with increasing longitude. The rapid change of compressional directions in the central East Sea prohibits accumulation of stress, causing rare shallow seismicity. High seismicity of reverse faulting events is observed at the fringes of the East Sea, in particular, around the east coast of the Korean Peninsula and the west coast of Japanese Islands, which correspond to paleo-rifted margins where compressional stresses are accumulated. The compressional stress field and active thrustal events suggest reverse activation of paleo-normal faults that were developed during the opening of the East Sea.",
author = "Hoseon Choi and Hong, {Tae Kyung} and Xiaobo He and Baag, {Chang Eob}",
year = "2012",
month = "10",
day = "17",
doi = "10.1016/j.tecto.2011.12.023",
language = "English",
volume = "572-573",
pages = "123--133",
journal = "Tectonophysics",
issn = "0040-1951",
publisher = "Elsevier",

}

Seismic evidence for reverse activation of a paleo-rifting system in the East Sea (Sea of Japan). / Choi, Hoseon; Hong, Tae Kyung; He, Xiaobo; Baag, Chang Eob.

In: Tectonophysics, Vol. 572-573, 17.10.2012, p. 123-133.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Seismic evidence for reverse activation of a paleo-rifting system in the East Sea (Sea of Japan)

AU - Choi, Hoseon

AU - Hong, Tae Kyung

AU - He, Xiaobo

AU - Baag, Chang Eob

PY - 2012/10/17

Y1 - 2012/10/17

N2 - The Japanese Islands were separated from the Eurasian plate due to continental rifting during the Oligocene to mid-Miocene, which caused the opening of the East Sea (Sea of Japan). Such tectonic evolution in the East Sea is important for understanding the evolution of back-arc regions with active convergent margins. To understand the evolution of the paleo-rifted back-arc region, we investigate seismicity, crustal seismic anisotropy, focal mechanism solutions and ambient stress field around the Korean Peninsula. The Korean Peninsula displays diffused seismicity with small and moderate earthquakes. Shallow earthquakes rarely occur in the central East Sea. The crustal fast shear-wave polarization directions in the Korean Peninsula are observed to vary in azimuth between 40° and 90°. The focal mechanism solutions are calculated by long period waveform inversions. The ambient stress field is calculated from the focal mechanism solutions. The compressional stress field in the Korean Peninsula is observed to be in ENE-WSW, which is consistent with the fast shear-wave polarization directions. The compressional stress directions in the East Sea progressively change from ENE to SE with increasing longitude. The rapid change of compressional directions in the central East Sea prohibits accumulation of stress, causing rare shallow seismicity. High seismicity of reverse faulting events is observed at the fringes of the East Sea, in particular, around the east coast of the Korean Peninsula and the west coast of Japanese Islands, which correspond to paleo-rifted margins where compressional stresses are accumulated. The compressional stress field and active thrustal events suggest reverse activation of paleo-normal faults that were developed during the opening of the East Sea.

AB - The Japanese Islands were separated from the Eurasian plate due to continental rifting during the Oligocene to mid-Miocene, which caused the opening of the East Sea (Sea of Japan). Such tectonic evolution in the East Sea is important for understanding the evolution of back-arc regions with active convergent margins. To understand the evolution of the paleo-rifted back-arc region, we investigate seismicity, crustal seismic anisotropy, focal mechanism solutions and ambient stress field around the Korean Peninsula. The Korean Peninsula displays diffused seismicity with small and moderate earthquakes. Shallow earthquakes rarely occur in the central East Sea. The crustal fast shear-wave polarization directions in the Korean Peninsula are observed to vary in azimuth between 40° and 90°. The focal mechanism solutions are calculated by long period waveform inversions. The ambient stress field is calculated from the focal mechanism solutions. The compressional stress field in the Korean Peninsula is observed to be in ENE-WSW, which is consistent with the fast shear-wave polarization directions. The compressional stress directions in the East Sea progressively change from ENE to SE with increasing longitude. The rapid change of compressional directions in the central East Sea prohibits accumulation of stress, causing rare shallow seismicity. High seismicity of reverse faulting events is observed at the fringes of the East Sea, in particular, around the east coast of the Korean Peninsula and the west coast of Japanese Islands, which correspond to paleo-rifted margins where compressional stresses are accumulated. The compressional stress field and active thrustal events suggest reverse activation of paleo-normal faults that were developed during the opening of the East Sea.

UR - http://www.scopus.com/inward/record.url?scp=84866857501&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84866857501&partnerID=8YFLogxK

U2 - 10.1016/j.tecto.2011.12.023

DO - 10.1016/j.tecto.2011.12.023

M3 - Article

AN - SCOPUS:84866857501

VL - 572-573

SP - 123

EP - 133

JO - Tectonophysics

JF - Tectonophysics

SN - 0040-1951

ER -