Seismic evidence of divergent rifting and subsequent deformation in the southern Japan Sea, and a Cenozoic tectonic synthesis of the eastern Eurasian margin

Itoh, Yasuto; Uno, Koji; Arato, Hiroyuki

doi:10.1016/j.jseaes.2005.09.008

Cited by 47 publications

(39 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Its western termination merged into the marginal fault of the Japan Sea and reactivated it in the opposite (sinistral) sense to its initial dextral activity during the Miocene backarc opening (Itoh 2001). Although the activity level seems to diminish eastward, Itoh et al (1997Itoh et al ( , 2006 showed a coeval deformation on the eastern SWJ backarc. If the regional event is linked with oceanic plate motion, the Philippine Sea plate probably imposed a northerly convergence at ca.…”

Section: Resultsmentioning

confidence: 96%

Evolutionary process of Beppu Bay in central Kyushu, Japan: a quantitative study of the basin-forming process controlled by plate convergence modes

2014

Self Cite

View full text Add to dashboard Cite

This integrated tectonic study reveals the basin-forming and deforming processes on an active margin. Southwest Japan (SWJ) is an island arc under the influence of oblique subduction of the Philippine Sea plate, which has provoked dextral slips on the arc-bisecting Median Tectonic Line (MTL). Plio-/Pleistocene sediments in Beppu Bay, a tectonic depression at the westernmost portion of the MTL, are categorized into lower (5~0.7 Ma), upper (0.7~0.3 Ma), and an auxiliary uppermost (0.3 Ma~present) unit in ascending order. Detailed seismic interpretation demonstrates that major structures in the deep interior of the basin are an older half-graben under a strong N-S extensional regime and a younger pull-apart sag that developed in a right-stepping part of the MTL as a result of late Quaternary-enhanced strike-slip rates on the fault. Sediments within the pull-apart have been deformed by later inversion events as a contraction phase arose. Conspicuous deformation of the hanging wall of the low-angle detachment of the basin was successfully reproduced by numerical modeling. Based on a discrete element method, this suggests that structural differences in the deformed sedimentary layers are caused by differences in the dip angles of the faults. Remarkable temporal changes in tectonic regimes around Beppu Bay and other areas of SWJ are probably related to transient modes of convergence, including the migration of the Euler pole, of the Philippine Sea plate since ca. 6 Ma.

show abstract

Section: Resultsmentioning

confidence: 96%

Evolutionary process of Beppu Bay in central Kyushu, Japan: a quantitative study of the basin-forming process controlled by plate convergence modes

2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…(a) Present configuration of southwest Japan and (b) its paleogeographic reconstruction before opening of the Japan Sea following [4]. Bending of the southwestern Japan arc caused by the middle Miocene collision event has been restored referring to paleomagnetic studies, expressed as the straightforward trend of the Median Tectonic Line.…”

Section: Geophysical Surveymentioning

confidence: 99%

“…In a series of pioneering paleomagnetic studies by Otofuji et al (e.g., [2,3]), a fan-shaped opening mode was advocated to explain the large rotation of the rifted block. Figure 1 shows the most probable paleoreconstruction of the southern part of the Japan Sea [4], in which jigsaw fitting of subsea continental fragments is carefully taken into account.…”

Section: Introductionmentioning

confidence: 99%

Post-Opening Deformation History of the Japan Sea Back-Arc Basin: Tectonic Processes on an Active Margin Governed by the Mode of Plate Convergence

Itoh¹

2018

Tectonics - Problems of Regional Settings

Self Cite

View full text Add to dashboard Cite

Three-dimensional structure of the Japan Sea back-arc basin is investigated based on an extensive reflection seismic survey. The process of the Oligocene to early Miocene rifting is described in reference to a geologic database, and the most likely paleoreconstruction of rifted continental fragments is presented. The back-arc region has been subjected to intermittent post-opening deformation events, which the author regards as side effects of temporal shifts in the convergence mode of the Philippine Sea Plate (PSP). The southern shelf of the Japan Sea appears to have suffered North-South strong contraction for a short period of time during the latest Miocene. Resumed convergence of the PSP was responsible for the regional tectonic event because frequent igneous intrusions within the upper Miocene series upon the back-arc shelf, which was confirmed by a borehole stratigraphic study, are suggestive of revitalized arc volcanism linked to dehydration of the subducted slab. During the Quaternary period, confined structure in varied forms developed on the shelf, which is related to the dextral wrench deformation of southwest Japan and the eventual arc-parallel crustal breakup along the back-arc region. Simultaneous highly oblique subduction of the PSP provoked the prevailing shear stress and conspicuous neotectonic deformation.

show abstract

“…They also pointed out two stages of formation of high-magnesium andesite, which is suggestive of thermal input around the continental margin. Such a thermal event may be related to ridge subduction as conceived by [26] or, alternatively, with an asthenospheric injection that provoked crustal thinning and deformation of the Far East [27].…”

Section: Time Sequence Of Igneous Activitymentioning

confidence: 99%

Cretaceous Research: A New Constraint on the Paleostress Regime of Southwest Japan Based on Microfabric Analysis of a Granitic Pluton

Itoh¹

2017

Dynamics of Arc Migration and Amalgamation - Architectural Examples From the NW Pacific Margin

Self Cite

View full text Add to dashboard Cite

Origin of a conspicuous microscopic fabric of a granitic pluton in the eastern part of southwest Japan, which has been an autochthonous component of the East Asian margin since the late Mesozoic, was elucidated through well-organized rock magnetic and geochronological investigations. The voluminous Late Cretaceous Toki Granite suffered a thermochemical event succeeding to its emplacement, which resulted in tightly grouped principal axes of the anisotropy of magnetic susceptibility (AMS). The magnetic fabrics originate from ferromagnetic and paramagnetic minerals precipitated upon the surface of fractures developed under regional tectonic stress. Together with previous studies of three-dimensional microcrack generation and intrusion sequence of dike swarms in the Toki Granite, temporal changes in the azimuths of AMS principal axes delineate a drastic shift in tectonic stress regime along the Asian continental margin from the Late Cretaceous to the Paleocene. This remarkable event is probably linked to a regional unconformity contemporaneously formed on the convergent margin.

show abstract

Seismic evidence of divergent rifting and subsequent deformation in the southern Japan Sea, and a Cenozoic tectonic synthesis of the eastern Eurasian margin

Cited by 47 publications

References 43 publications

Evolutionary process of Beppu Bay in central Kyushu, Japan: a quantitative study of the basin-forming process controlled by plate convergence modes

Evolutionary process of Beppu Bay in central Kyushu, Japan: a quantitative study of the basin-forming process controlled by plate convergence modes

Post-Opening Deformation History of the Japan Sea Back-Arc Basin: Tectonic Processes on an Active Margin Governed by the Mode of Plate Convergence

Cretaceous Research: A New Constraint on the Paleostress Regime of Southwest Japan Based on Microfabric Analysis of a Granitic Pluton

Contact Info

Product

Resources

About