Depositional sequence of the Post-LGM incised-valley fill controlled by seismic crustal deformation and large-scale lahars: An example of the core obtained from the Sukumo coastal lowland along the Nankai Trough, Japan

太, 七山; 龍彦, 山口; 利典, 中西; 智大, 辻; 倫治, 池田; 康生, 近藤; 美智子, 三輪; 真二, 杉山; 一成, 木村

doi:10.5575/geosoc.2020.0023

Cited by 3 publications

(45 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…were not buried at that time, and that there were no deltas or coastal lowlands near the mouth of the Matsuda River (Nanayama et al, 2020).…”

Section: Introductionmentioning

confidence: 97%

“…Segment N5 0 was additionally cited by Furumura et al (2011). (b) Topography and bathymetry of southwestern Japan, modified after Nanayama and Maeno (2019) and Nanayama et al (2020). The base map was prepared by Kiyoshi Kishimoto of AIST.…”

Section: Introductionmentioning

confidence: 99%

“…Possible tsunami deposits attributed to the 7.3 ka Kikai eruption have been reported as far from the caldera as Northwestern Kyushu. Okamura Nearby tidal records at the ports of Tosashimizu on Cape Ashizuri and Uwajima north of the Bungo Channel indicate that sea level has risen by about 10 cm since 1955 (Nanayama et al, 2020). This suggests that the sea level is rising slightly on the Southwestern coast of Shikoku.…”

Section: Introductionmentioning

confidence: 99%

“…For example, monuments at the Haitaka Shrine on Oshima Island (Figure 2(b)) record that tsunamis reached an elevation of 9.8 m during the 1707 Hoei earthquake and 3.2 m during the 1854 Ansei Nankai earthquake (Murakami et al, 1996). At the time of the 1946 Showa Nankai earthquake (M w 8.1-8.4; Usami et al, 2013), the ground in the urban area of Sukumo City sank 30 cm, and the seawater brought by the tsunami remained for a long time (Nanayama et al, 2020). Documents describe widespread subsidence during the 1707 Hoei earthquake, which was followed by three large tsunamis that desolated the fields with lingering seawater.…”

Section: Introductionmentioning

confidence: 99%

“…Documents describe widespread subsidence during the 1707 Hoei earthquake, which was followed by three large tsunamis that desolated the fields with lingering seawater. In the Nankai Trough giant earthquake model released by the Cabinet Office in August 2012, land subsidence as great as 2.4 m is expected in the Sukumo lowland (Nanayama et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Great earthquake at 7.3 ka inferred from tsunami deposits in the Sukumo Bay area, Southwestern Japan

et al. 2021

Self Cite

View full text Add to dashboard Cite

Tsunami deposits in Kyushu Island, Southwestern Japan, have been attributed to the 7.3 ka Kikai caldera eruption, but their origin has not been confirmed. We analyzed an 83-cm-thick Holocene event deposit in the SKM core, obtained from incised valley fill in the coastal lowlands near Sukumo Bay, Southwestern Shikoku Island. We confirmed that the event deposit contains K-Ah volcanic ash from the 7.3 ka eruption. The base of the event deposit erodes the underlying inner-bay mud, and the deposit contains material from outside the local terrestrial and marine environment, including angular quartz porphyry from a small inland exposure, oyster shell debris, and a coral fragment. Benthic foraminifers and ostracods in the deposit indicate

show abstract

“…were not buried at that time, and that there were no deltas or coastal lowlands near the mouth of the Matsuda River (Nanayama et al, 2020).…”

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Great earthquake at 7.3 ka inferred from tsunami deposits in the Sukumo Bay area, Southwestern Japan

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

High-frequency depositional sequence of the upper Quaternary deposits controlled by sediment supply: A case study of an inland basin in central Japan

Hatano

Kawano

Yoshida

2023

Palaeogeography, Palaeoclimatology, Palaeoecology

View full text Add to dashboard Cite

Middle Holocene relative sea‐level changes and vertical tectonic crustal movements on Shikoku Island near the Nankai Trough, Japan

et al. 2022

Self Cite

View full text Add to dashboard Cite

The Philippine Sea plate subducts beneath the Eurasia plate at the Nankai Trough, northwestern Pacific, causing crustal deformation, mega‐thrust earthquakes, and tsunami events. Shikoku Island, 150 km northwest of the trough, experiences both coseismic and interseismic deformation. Coastal sediments potentially record vertical crustal movements as relative sea level (RSL) changes. We studied sedimentary facies and microfossil ostracodes in core SKM from southwestern Shikoku Island for evidence of middle Holocene tsunami events and deformation. The core sediments included nine event layers corresponding to storm or tsunami events. Using modern analog techniques, we estimated RSLs from the ostracode assemblages of core SKM and 13 other cores from Shikoku Island and the surrounding region. Then, we subtracted RSL changes due to glacio‐hydro isostatic adjustment from the estimated RSLs to estimate vertical tectonic movement rates in these cores between 8.6 and 4.7 ka. The inferred RSL changes suggest that the Sukumo site has experienced both uplift and subsidence since 8.6 ka. Before 6.6 ka, rates of tectonic crustal movement were higher than the modern‐day rate, and its spatial distribution also differed. After 6.6 ka, tectonic crustal movement showed a similar spatial pattern and occurred at rates close to the modern day interseismic rate. The spatial pattern and rates of tectonic crustal movement could be caused by changes in rupture areas between the Eurasia and the Philippine Sea plates beneath the Shikoku Island and in stress condition of the asthenosphere. Some of the vertical displacements can be explained by the movements of local active faults.

show abstract

Depositional sequence of the Post-LGM incised-valley fill controlled by seismic crustal deformation and large-scale lahars: An example of the core obtained from the Sukumo coastal lowland along the Nankai Trough, Japan

Cited by 3 publications

References 54 publications

Great earthquake at 7.3 ka inferred from tsunami deposits in the Sukumo Bay area, Southwestern Japan

Great earthquake at 7.3 ka inferred from tsunami deposits in the Sukumo Bay area, Southwestern Japan

High-frequency depositional sequence of the upper Quaternary deposits controlled by sediment supply: A case study of an inland basin in central Japan

Middle Holocene relative sea‐level changes and vertical tectonic crustal movements on Shikoku Island near the Nankai Trough, Japan

Contact Info

Product

Resources

About