Identification and correlation of visible tephras in the Lake Suigetsu SG06 sedimentary archive, Japan: chronostratigraphic markers for synchronising of east Asian/west Pacific palaeoclimatic records across the last 150 ka

Fujiwara

et al. 2016

Earth-Science Reviews

Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. ABSTRACTThe Nankai-Suruga Trough, the subduction zone that lies immediately south of Japan's densely populated southern coastline, generates devastating great earthquakes (magnitude > 8) characterised by intense shaking, crustal deformation and tsunami generation. Forecasting the hazards associated with future earthquakes along this >700 km long fault requires a comprehensive understanding of past fault behaviour. While the region benefits from a long and detailed historical record, palaeoseismology has the potential to provide a longer-term perspective and additional crucial insights. In this paper, we summarise the current state of knowledge regarding geological evidence for past earthquakes and tsunamis along the Nankai-Suruga Trough. Incorporating literature originally published in both Japanese and English and enhancing available results with new age modelling approaches, we summarise and critically evaluate evidence from a wide variety of sources. Palaeoseismic evidence includes uplifted marine terraces and biota, marine and lacustrine turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. While 75 publications describe proposed evidence from more than 70 sites, only a limited number provide compelling, well-dated evidence. The best available records enable us to map the most likely rupture zones of twelve earthquakes that occurred during the historical period. This spatiotemporal compilation suggests that the AD 1707 earthquake ruptured almost the full length of the subduction zone and that earthquakes in AD 1361 and 684 may have been predecessors of similar magnitude. Intervening earthquakes were of lesser magnitude, highlighting the variability in rupture mode that characterises the Nankai-Suruga Trough. Intervals between ruptures of the same seismic segment range from less than 100 to more than 450 years during the historical period. Over longer timescales, palaeoseismic evidence suggests intervals between earthquakes ranging from 100 to 700 years, however these figures reflect a range of thresholds controlling the creation and preservation of evidence at any given site as well as the genuine intervals between earthquakes. At present, there is no geological data that suggest the occurrence of a larger magnitude earthquake than that experienced in AD 1707, however few studies have sought to establish the relative magnitudes of different earthquake and tsunami events along the Nankai-Suruga Trough. Alongside the lack of...

Section: The Western Tōnankai (C) Segmentmentioning

confidence: 99%

A systematic review of geological evidence for Holocene earthquakes and tsunamis along the Nankai-Suruga Trough, Japan

Fujiwara

et al. 2016

Earth-Science Reviews

“…Volcanic ash, found far from the source, however, is different from dust. First, it signals a strong explosive eruption; second, many tephras can be connected to their source volcanoes or volcanic zones via their unique geochemical fingerprint (e.g., Kutterolf et al, 2008a;Gudmundsdóttir et al, 2011;Lane et al, 2011;Smith et al, 2011bSmith et al, , 2013Tomlinson et al, 2015). With recent advances in microanalytical techniques, the composition of micronsized individual ash particles can be characterized.…”

Section: New Advances In Tephra Researchmentioning

confidence: 99%

“…Further afield, eruptive histories are being revisited from distal tephra studies in marine, lake and peat deposits as well as in the ice caps (e.g., Shane and Hoverd, 2002;Wulf et al, 2004Wulf et al, , 2008Wulf et al, , 2012Kutterolf et al, 2008a;Kuehn and Negrini, 2010;Sulpizio et al, 2010a,b;Dunbar and Kurbatov, 2011;Abbott and Davies, 2012;Narcisi et al, 2012;Pyne-O'Donnell et al, 2012;Jensen et al, 2013;Smith et al, 2013;Davies et al, 2014;van den Bogaard et al, 2014;Bourne et al, 2015a,b;Lane et al, 2015). By now, distal tephra and cryptotephra research has been successfully undertaken in many regions including Greenland (e.g., Abbott et al, 2012;Abbott and Davies, 2012;Coulter et al, 2012;Bourne et al, 2015b); North Atlantic (e.g., Lacasse and Garbe-Schönberg, 2001;Brendryen et al, 2011;Gudmundsdóttir et al, 2012;Blockley et al, 2014;Davies et al, 2014;Griggs et al, 2014;Voelker and Haflidason, 2015); European mainland (e.g., Caron et al, 2010;Sulpizio et al, 2010a,b;Lane et al, 2011Lane et al, , 2015Lawson et al, 2012); Mediterranean (Siani et al, 2004;Wulf et al, 2004Wulf et al, , 2008Wulf et al, , 2012Paterne et al, 2008;…”

Section: Record Of Explosive Eruptions: Identification and Dating Of mentioning

confidence: 99%

Tephra without Borders: Far-Reaching Clues into Past Explosive Eruptions

2015

This review is intended to highlight recent exciting advances in the study of distal (>100 km from the source) tephra and cryptotephra deposits and their potential application for volcanology. Geochemical correlations of tephra between proximal and distal locations have extended the geographical distribution of tephra over tens of millions square kilometers. Such correlations embark on the potential to reappraise volume and magnitude estimates of known eruptions. Cryptotephra investigations in marine, lake, and ice-core records also give rise to continuous chronicles of large explosive eruptions many of which were hitherto unknown. Tephra preservation within distal ice sheets and varved lake sediments permit precise dating of parent eruptions and provide new insight into the frequency of eruptions. Recent advances in analytical methods permit an examination of magmatic processes and the evolution of the whole volcanic belts at distances of hundreds and thousands of kilometers from source. Distal tephrochronology has much to offer volcanology and has the potential to significantly contribute to our understanding of sizes, recurrence intervals and geochemical make-up of the large explosive eruptions.

Prog. in Earth and Planet. Sci.

“…For example, fluctuations in East Asian monsoons are thought to be recorded in the sediments of Lake Biwa (Kuwae et al 2002;Nakagawa et al 2008), Lake Suigetsu (Nakagawa et al 2003), and the Japan Sea Ikehara 2003;Tada 2004;Ikehara and Fujine 2012). Because Lake Biwa and Lake Suigetsu are located close to the Japan Sea, several tephras found in Lake Biwa (Yoshikawa and Inouchi 1993;Nagahashi et al 2004;Satoguchi et al 2008) and Lake Suigetsu (Smith et al 2013), such as the K-Ah, U-Oki, AT, and Aso-4 tephras, also occur in the Japan Sea (e.g., Arai et al 1981;Furuta et al 1986;Nakajima et al 1996) and can therefore connect those different depositional environments.…”

Section: Tephra As a Paleoceanographic And Paleoclimatological Toolmentioning

confidence: 99%

Marine tephra in the Japan Sea sediments as a tool for paleoceanography and paleoclimatology

Ikehara

2015

Tephra is a product of large and explosive volcanic events and can travel thousands of kilometers before deposition. Consequently, tephra deposits are common in terrestrial, lacustrine, marine, and glacial environments. Because tephra deposition is a geologically synchronous event, tephras constitute important isochrones in the Quaternary sequence, not only in Japan but also throughout the northwest Pacific and its marginal seas. As a result, establishing the chronostratigraphic order of tephra deposits is an effective tool for assessing local and regional stratigraphies and for correlating events among sites. For example, tephrostratigraphy can provide precise chronological constraints for other stratigraphic data, such as magneto-and biostratigraphic data. Spatiotemporal variability in the occurrence and geochemistry of tephras can also be used to trace the magmatic evolution of island arcs and their relationships to regional tectonics. In a paleoclimatic context, tephra deposits allow the correlation of past climate events among terrestrial, lacustrine, and marine environments. Tephrochronology is also a fundamental element used in reconstructing the marine reservoir effect, where the ages of tephra in marine and terrestrial settings are compared. Therefore, tephra is a valuable tool not only in stratigraphy, chronology, and volcanology but also in paleoceanography and paleoclimatology.