DOI: 10.1016/j.quascirev.2016.08.003
Scopus记录号: 2-s2.0-84981748235
论文题名: Detection limits of tidal-wetland sequences to identify variable rupture modes of megathrust earthquakes
作者: Shennan I. ; Garrett E. ; Barlow N.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 150 起始页码: 1
结束页码: 30
语种: 英语
英文关键词: Earthquake
; Holocene
; Paleoseismology
; Sea-level change
; Tsunami
Scopus关键词: Earthquakes
; Forecasting
; Peat
; Sea level
; Seismology
; Tsunamis
; Wetlands
; Holocenes
; Megathrust earthquakes
; Methodological frameworks
; Multiple earthquake cycles
; Paleoseismology
; Relative sea-level changes
; Rigorous evaluation
; Sealevel change
; Geophysics
; coseismic process
; detection method
; earthquake event
; earthquake rupture
; Holocene
; intertidal environment
; paleoseismicity
; sea level change
; seismology
; subduction zone
; subsidence
; tsunami
; uplift
; wetland
; Alaska
; United States
英文摘要: Recent paleoseismological studies question whether segment boundaries identified for 20th and 21st century great, >M8, earthquakes persist through multiple earthquake cycles or whether smaller segments with different boundaries rupture and cause significant hazards. The smaller segments may include some currently slipping rather than locked. In this review, we outline general principles regarding indicators of relative sea-level change in tidal wetlands and the conditions in which paleoseismic indicators must be distinct from those resulting from non-seismic processes. We present new evidence from sites across southcentral Alaska to illustrate different detection limits of paleoseismic indicators and consider alternative interpretations for marsh submergence and emergence. We compare predictions of coseismic uplift and subsidence derived from geophysical models of earthquakes with different rupture modes. The spatial patterns of agreement and misfits between model predictions and quantitative reconstructions of coseismic submergence and emergence suggest that no earthquake within the last 4000 years had a pattern of rupture the same as the Mw 9.2 Alaska earthquake in 1964. From the Alaska examples and research from other subduction zones we suggest that If we want to understand whether a megathrust ruptures in segments of variable length in different earthquakes, we need to be site-specific as to what sort of geological-based criteria eliminate the possibility of a particular rupture mode in different earthquakes. We conclude that coastal paleoseismological studies benefit from a methodological framework that employs rigorous evaluation of five essential criteria and a sixth which may be very robust but only occur at some sites: 1 – lateral extent of peat-mud or mud-peat couplets with sharp contacts; 2 – suddenness of submergence or emergence, and replicated within each site; 3 – amount of vertical motion, quantified with 95% error terms and replicated within each site; 4 – syncroneity of submergence and emergence based on statistical age modelling; 5 – spatial pattern of submergence and emergence; 6 – possible additional evidence, such as evidence of a tsunami or liquefaction concurrent with submergence or emergence. We suggest that it is possible to consider detection limits as low as 0.1–0.2 m coseismic vertical change. © 2016 资助项目: Work supported by the U.S. Geological Survey earthquake hazards project awards G13AP00051, G12AP20084, G10AP00075 and G09AP00105 (The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government) and NERC Radiocarbon Allocations 935.0901 and 1339.1008. Barlow thanks The Royal Society Dudley Stamp Memorial Fund, The Royal Geographical Society Monica Cole Research Grant and Department of Geography, Durham University for financial support whilst undertaking fieldwork at Hope and Bird Point. Brian Atwater, Julius Jara-Muñoz and Alan Nelson for comments on a previous version.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59451
Appears in Collections: 过去全球变化的重建
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作者单位: Sea Level Research Unit, Department of Geography, Durham University, Durham, United Kingdom; Geological Survey of Belgium, Royal Belgian Institute of Natural Sciences, Rue Jenner, Brussels, Belgium
Recommended Citation:
Shennan I.,Garrett E.,Barlow N.. Detection limits of tidal-wetland sequences to identify variable rupture modes of megathrust earthquakes[J]. Quaternary Science Reviews,2016-01-01,150