DOI: 10.1016/j.palaeo.2012.04.006
论文题名: Early Holocene large-scale meltwater discharge from Greenland documented by foraminifera and sediment parameters
作者: Seidenkrantz M.-S. ; Ebbesen H. ; Aagaard-Sørensen S. ; Moros M. ; Lloyd J.M. ; Olsen J. ; Knudsen M.F. ; Kuijpers A.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2013
卷: 391 起始页码: 71
结束页码: 81
语种: 英语
英文关键词: 8.2ka event
; Early Holocene
; Foraminifera
; Greenland
; Magnetic susceptibility
; Meltwater discharge
; Sediment properties
英文摘要: Records of foraminiferal assemblages combined with lithological properties (grain size, magnetic parameters and XRF data) of marine sediment cores from West Greenland coastal waters and the adjacent Labrador Sea document widespread early Holocene meltwater discharge. This discharge is concluded to originate from large-scale melting of the Greenland Ice Sheet (GIS) having started prior to 8600. cal.yr. BP and ended at about 7700-7500. cal.yr. BP, when the GIS margin had withdrawn from the fjords and become mainly land-based. The benthic foraminiferal record from one of the coastal sites mainly reflects West Greenland Current (WGC) subsurface water properties and to a minor degree surface productivity. The most significant feature in this record is an abrupt shift to a higher-productivity regime around ~. 7700. cal.yr. BP. We suggest that the cessation of a widespread GIS meltwater discharge at that time favoured an increased influence of (sub)surface water of Atlantic origin and initiation of modern subpolar gyre circulation enabling Labrador Sea deep convection. Further offshore, a record of planktonic foraminiferal assemblages shows an oceanographic change at ca. 9500. cal.yr. BP, whilst a gradual but marked change in the planktonic foraminiferal assemblage between 8800 and 7000. cal.yr. BP may be related to a narrowing of the WGC low-salinity surface water belt. The oceanic regime off West Greenland prior to ~. 7800. cal.yr. BP was thus characterised by the presence of a permanent and widespread meltwater surface layer, presumably preventing deep convection in this region. Apart from indications of a slight decrease in meltwater discharge by the benthic foraminiferal fauna data, neither of the records show any clear signal of a regionally important 8.2. ka event. © 2012 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69570
Appears in Collections: 过去全球变化的重建
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作者单位: Centre for Past Climate Studies, Department of Geoscience, Aarhus University, Denmark; Geological Survey of Denmark and Greenland (GEUS), Denmark; Institute for Baltic Sea Research, Warnemünde, Germany; Uni Bjerknes Centre, Bergen, Norway; Department of Geography, University of Durham, United Kingdom; Centre for Climate, The Environment and Chronology (14CHRONO), Queen's University Belfast, United Kingdom; Department of Geology, Tromsø University, Norway; AMS 14C Dating Centre, Department of Physics and Astronomy, Aarhus University, Denmark
Recommended Citation:
Seidenkrantz M.-S.,Ebbesen H.,Aagaard-Sørensen S.,et al. Early Holocene large-scale meltwater discharge from Greenland documented by foraminifera and sediment parameters[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2013-01-01,391