DOI: 10.1016/j.quascirev.2012.10.022
Scopus记录号: 2-s2.0-84870234173
论文题名: Exposure-age record of Holocene ice sheet and ice shelf change in the northeast Antarctic Peninsula
作者: Balco G. ; Schaefer J.M.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 59 起始页码: 101
结束页码: 111
语种: 英语
英文关键词: Antarctic Peninsula
; Cosmogenic-nuclide geochronology
; Deglaciation
; Exposure dating
; Larsen Ice Shelf
; Weddell Sea
Scopus关键词: Antarctic Peninsula
; Deglaciations
; Exposure dating
; Ice shelves
; Weddell Sea
; Geochronology
; Glacial geology
; Isotopes
; Sea level
; Ice
; coastal zone
; cosmogenic radionuclide
; deglaciation
; geochronology
; Holocene
; ice sheet
; ice shelf
; ice thickness
; Last Glacial Maximum
; sea level
; age determination
; Antarctic Peninsula
; Antarctica
; Larsen Ice Shelf
; Southern Ocean
; Weddell Sea
; West Antarctica
; Drygalski Glacier
; East Antarctica
英文摘要: This paper describes glacial-geologic observations and cosmogenic-nuclide exposure ages from ice-free areas adjacent to the Sjögren, Boydell, and Drygalski Glaciers of the northeast Antarctic Peninsula. These provide a record of Holocene glacier and ice shelf change in this region. Early Holocene ice surface elevation near the present coastline was locally at least 500 m above present sea level, but our observations do not constrain the maximum thickness of Last Glacial Maximum (LGM) ice or the time at which it was attained. The boundary between frozen-based and wet-based ice reached a maximum elevation of 100-150 m above present sea level. The ice surface elevation decreased from 300-500 m elevation to near present sea level between 9 ka and ca 4 ka. Below 160 m elevation, we observed a bimodal distribution of apparent exposure ages in which a population of glacially transported clasts with mid-Holocene exposure ages coexists with another that has exposure ages of 100-600 years. We consider the most likely explanation for this to be i) complete deglaciation of currently ice-free areas, which presumably required the absence of ice shelves, at 3.5-4.5 ka, followed by ii) subsequent ice shelf formation and grounding line advance after ca 1.4 ka, and iii) complete re-exposure of the sites after ice shelf breakup and glacier surface lowering in recent decades. This explanation is consistent with marine sedimentary records indicating that ice shelves in the Prince Gustav Channel and Larsen A embayment were absent in the middle to late Holocene and were re-established within the last 2000 years. © 2012 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60740
Appears in Collections: 过去全球变化的重建
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作者单位: Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, United States; Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, United States
Recommended Citation:
Balco G.,Schaefer J.M.. Exposure-age record of Holocene ice sheet and ice shelf change in the northeast Antarctic Peninsula[J]. Quaternary Science Reviews,2013-01-01,59