DOI: 10.1016/j.quascirev.2014.10.010
Scopus记录号: 2-s2.0-85027927651
论文题名: Reconstructing paleoseismic deformation, 2: 1000 years of great earthquakes at Chucalén, south central Chile
作者: Garrett E. ; Shennan I. ; Woodroffe S.A. ; Cisternas M. ; Hocking E.P. ; Gulliver P.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2015
卷: 113 起始页码: 112
结束页码: 122
语种: 英语
英文关键词: Diatoms
; Earthquake reconstruction
; Paleoseismicity
; Relative sea level
; Transfer functions
; Tsunami
Scopus关键词: Algae
; Biostratigraphy
; Geophysics
; Phytoplankton
; Sea level
; Stratigraphy
; Subsidence
; Transfer functions
; Tsunamis
; Diatoms
; Earthquake recurrence intervals
; Historical earthquakes
; Megathrust earthquakes
; Paleoseismicity
; Prehistoric earthquakes
; Relative sea level
; Relative sea level rise
; Earthquakes
; biostratigraphy
; diatom
; earthquake magnitude
; earthquake recurrence
; fossil assemblage
; lithostratigraphy
; paleoseismicity
; peat
; prehistoric
; quantitative analysis
; reconstruction
; sea level change
; subsidence
; transfer function
; Chile
; Bacillariophyta
英文摘要: In this paper we adopt a quantitative biostratigraphic approach to establish a 1000-year-long coastal record of megathrust earthquake and tsunami occurrence in south central Chile. Our investigations focus on a site in the centre of the rupture segment of the largest instrumentally recorded earthquake, the AD 1960 magnitude 9.5 Chile earthquake. At Chucalén coseismic subsidence in 1960 is recorded in the lithostratigraphy and biostratigraphy of coastal marshes, with peat overlain by minerogenic sediment and changes in the assemblages of diatoms (unicellular algae) indicating an abrupt increase in relative sea level. In addition to the 1960 earthquake, the stratigraphy at Chucalén records three earlier earthquakes, the historically documented earthquake of 1575 and two prehistoric earthquakes, radiocarbon dated to AD 1270-1450 and 1070-1220. Laterally extensive sand sheets containing marine or brackish diatom assemblages suggest tsunami deposition associated with at least two of the three pre-1960 earthquakes. The record presented here suggests a longer earthquake recurrence interval, averaging 270 years, than the historical recurrence interval, which averages 128 years. The lack of geologic evidence at Chucalén of two historically documented earthquakes, in 1737 and 1837, supports the previously suggested hypothesis of variability in historical earthquake characteristics. Our estimates of coseismic land-level change for the four earthquakes range from meter-scale subsidence to no subsidence or slight uplift, suggesting earthquakes completing each ~270 year cycle may not share a common, characteristic slip distribution. The presence of buried soils at elevations below their modern equivalents implies net relative sea-level rise over the course of the Chucalén paleoseismic record, in contrast to relative sea-level fall over preceding millennia inferred from sites on the mainland. Sea-level rise may contribute to the preservation of evidence for multiple earthquakes during the last millennium, while net relative sea-level fall over the last 2000-5000 years may explain the lack of evidence for older earthquakes. © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59978
Appears in Collections: 过去全球变化的重建
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作者单位: Durham University, Sea Level Research Unit, Department of Geography, South Road, Durham, United Kingdom; Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Altamirano, Valparaíso, Chile; Northumbria University, Department of Geography, Ellison Place, Newcastle upon Tyne, United Kingdom; NERC Radiocarbon Facility, SUERC, Scottish Enterprise Technology Park, Rankine Avenue, East Kilbride, United Kingdom
Recommended Citation:
Garrett E.,Shennan I.,Woodroffe S.A.,et al. Reconstructing paleoseismic deformation, 2: 1000 years of great earthquakes at Chucalén, south central Chile[J]. Quaternary Science Reviews,2015-01-01,113