DOI: 10.1016/j.quascirev.2013.12.005
Scopus记录号: 2-s2.0-84896100726
论文题名: Glacial history of sub-Antarctic South Georgia based on the submarine geomorphology of its fjords
作者: Hodgson D.A. ; Graham A.G.C. ; Griffiths H.J. ; Roberts S.J. ; Cofaigh C.T. ; Bentley M.J. ; Evans D.J.A.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2014
卷: 89 起始页码: 129
结束页码: 147
语种: 英语
英文关键词: Geochronology
; Geomorphology
; Glacial history
; Glaciation
; Swath bathymetry
Scopus关键词: Bathymetry
; Geochronology
; Geomorphology
; Isotopes
; Landforms
; Submarines
; Bathymetric survey
; Central Patagonia
; Cosmogenic isotopes
; Glacial geomorphology
; Glacial history
; Glaciation
; Last Glacial Maximum
; Swath bathymetry
; Glacial geology
; fjord
; geomorphology
; glacial history
; glaciation
; glacier advance
; glacier retreat
; ice cap
; Last Glacial Maximum
; moraine
; swath bathymetry
; Patagonia
英文摘要: We present multibeam swath bathymetric surveys of the major fjords surrounding the sub-Antarctic island of South Georgia to characterise the glacial geomorphology and to identify the relative timings and extent of past glacial advance and retreat. Bathymetry data revealed a range of glacial features including terminal, retreat and truncated moraines, deep (distal) outer and shallow (proximal) inner basins and cross shelf troughs. These provide evidence of glacial advance and retreat through several glacial cycles. A near consistent pattern of large scale submarine geomorphological features was observed in the different fjords suggesting a similar response of margins of the island ice cap to past climate forcing. A relative chronology based on the relationships between the submarine features with their radiocarbon and cosmogenic isotope dated terrestrial counterparts suggests that widely observed inner basin moraines date from the last major glacial advance or Last Glacial Maximum, while deep basin moraines may date from an earlier (pre-LGM) more extensive glaciation, which we speculate corresponds to MIS6. On the sides of the deep basins a series of truncated moraines show ice advance positions from preceding glacial periods. The cross shelf troughs, and mid-trough moraines are interpreted as the product of much more extensive glaciations that predate the fjord geomorphology mapped here, thus possibly older than MIS6. This hypothesis would suggest that South Georgia followed a glacial history similar to that of central Patagonia (46°S) where a series of Pleistocene glaciations (of MIS 20 and younger) extended beyond LGM limits, with the most extensive glacial advance occurring at c. 1.1Ma. © 2014 The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60341
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, United Kingdom; Department of Geography, Durham University, South Road, Durham DH1 3LE, United Kingdom; School of Geography, College of Life and Environmental Sciences, University of Exeter, Amory Building, Rennes Drive, Exeter EX4 4RJ, United Kingdom
Recommended Citation:
Hodgson D.A.,Graham A.G.C.,Griffiths H.J.,et al. Glacial history of sub-Antarctic South Georgia based on the submarine geomorphology of its fjords[J]. Quaternary Science Reviews,2014-01-01,89