气候变化领域集成服务门户(CCPortal): Coseismic coastal subsidence associated with unusually wide rupture of prehistoric earthquakes on the Kamchatka subduction zone: A record in buried erosional scarps and tsunami deposits

CCPortal

DOI	10.1016/j.quascirev.2020.106171
	Coseismic coastal subsidence associated with unusually wide rupture of prehistoric earthquakes on the Kamchatka subduction zone: A record in buried erosional scarps and tsunami deposits
	Pinegina T.K.; Bourgeois J.; Bazanova L.I.; Zelenin E.A.; Krasheninnikov S.P.; Portnyagin M.V.
发表日期	2020
ISSN	0277-3791
卷号	233
英文摘要	The prograding strand plain of Avachinsky Bay, Kamchatka, Russia, along the highly active Kamchatka subduction zone, exhibits geological evidence--buried erosional scarps--for coseismic subsidence only three times in the last four millennia, the last event about 1200 years ago. This same coast has a historical record (since A.D. 1737) of five subduction-zone earthquakes with large tsunami runup (>5 m), the last of which was the 1952 Mw 9 Kamchatka earthquake, and a geological record of more than 30 large tsunamis in the last 4000 years. This rarity of buried scarps relative to large earthquakes contrasts with the Cascadia strand plain in SW Washington State, where most or all large events are represented by buried scarps. A strong factor in the amplitude and sign of coseismic deformation is distance from the seaward edge of a subduction zone (the trench); the Avachinsky Bay coastline is 180–200 km from the trench, with ∼25° slab dip, requiring unusually wide ruptures to generate significant coseismic subsidence. This coastal zone is undergoing net subsidence approximately equivalent to the total of the three coseismic subsidence events, generating a sequence of beach ridges that increase in elevation seaward. Each of the three unusual (coseismic subsidence) events comprises a) an earthquake whose deformation field caused b) onshore coseismic subsidence, thus local sea-level rise and c) sufficient deformation offshore to produce a large tsunami; a,b,c followed by d) a period of coastal erosion and shoreline retreat, leaving e) an erosional beach scarp that was f) subsequently buried once progradation resumed. We identified, dated and correlated the scarps and tsunami deposits from these events with several field methods, including trenching, tephrostratigraphy and ground penetrating radar. The scarps were correlated over an alongshore distance of 50–70 km. The most recent event (event 1) occurred ∼800 cal AD (1100–1250 14С years BP), event 2–600 cal BC (2400–2450 14С years BP), and event 3–1700 cal BC (3300–3500 14С years BP). We developed methods for quantifying subsidence, coastal erosion and tsunami size for each of these events. All three retain evidence of ∼0.4–1.2 m of coseismic subsidence; coastal erosion in the case of event 1 averaged more than 100 m; all three “event” tsunamis were amongst the largest in the last 4000 years. © 2020 Elsevier Ltd
英文关键词	Beach ridges; Buried erosional scarps; Coastal; Coseismic coastal subsidence; Geomorphology; Ground penetrating radar; Holocene; Kamchatka subduction zone; Paleoseismology; Tephrochronology; Tsunami deposits
语种	英语
scopus关键词	Beaches; Deformation; Deposits; Earthquakes; Erosion; Geological surveys; Geology; Geomorphology; Geophysical prospecting; Ground penetrating radar systems; Offshore oil well production; Sea level; Tsunamis; Beach ridge; Buried erosional scarps; Coastal; Ground Penetrating Radar; Holocenes; Paleoseismology; Subduction zones; Tephrochronology; Tsunami deposits; Subsidence; beach ridge; coastal erosion; coastal zone; coseismic process; deformation; earthquake rupture; erosion; geological record; geomorphology; ground penetrating radar; historical record; Holocene; paleoseismicity; prehistoric; progradation; subduction zone; subsidence; tephrochronology; tsunami; Kamchatka; Russian Federation; Russian Federation; United States; Washington [United States]
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151547
作者单位	Institute of Volcanology & Seismology FEB RAS, Petropavlovsk-Kamchatsky, Piip Boulevard 9683006, Russian Federation; Department of Earth and Space Sciences, University of Washington, 4000 15th Ave NE, Seattle, WA 98195-1310, United States; Geological Institute, Pyzhevsky Lane 7, Moscow, 119017, Russian Federation; V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry, Kosygin St. 19, Moscow, 119991, Russian Federation; GEOMAR Helmholtz Center for Ocean Research Kiel, Wischhofstrasse 1-3, Kiel, 24148, Germany
推荐引用方式 GB/T 7714	Pinegina T.K.,Bourgeois J.,Bazanova L.I.,et al. Coseismic coastal subsidence associated with unusually wide rupture of prehistoric earthquakes on the Kamchatka subduction zone: A record in buried erosional scarps and tsunami deposits[J],2020,233.
APA	Pinegina T.K.,Bourgeois J.,Bazanova L.I.,Zelenin E.A.,Krasheninnikov S.P.,&Portnyagin M.V..(2020).Coseismic coastal subsidence associated with unusually wide rupture of prehistoric earthquakes on the Kamchatka subduction zone: A record in buried erosional scarps and tsunami deposits.Quaternary Science Reviews,233.
MLA	Pinegina T.K.,et al."Coseismic coastal subsidence associated with unusually wide rupture of prehistoric earthquakes on the Kamchatka subduction zone: A record in buried erosional scarps and tsunami deposits".Quaternary Science Reviews 233(2020).