DOI: 10.1016/j.quascirev.2016.03.028
Scopus记录号: 2-s2.0-84966731077
论文题名: Paleo-environmental gateways in the eastern Canadian arctic – Recent isotope hydrology and diatom oxygen isotopes from Nettilling Lake, Baffin Island, Canada
作者: Chapligin B. ; Narancic B. ; Meyer H. ; Pienitz R.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 147 起始页码: 379
结束页码: 390
语种: 英语
英文关键词: Arctic
; Biogenic silica
; Climate-reconstruction
; Marine-lacustrine transition
; Post-glacial
Scopus关键词: Algae
; Hydrology
; Lakes
; Nickel
; Phytoplankton
; Silica
; Arctic
; Biogenic silica
; Climate reconstruction
; Marine-lacustrine transition
; Post-glacial
; Isotopes
; biogenic mineral
; diatom
; estuarine front
; Holocene
; isotopic analysis
; isotopic composition
; oxygen isotope
; paleoceanography
; paleoclimate
; paleoenvironment
; Postglacial
; proxy climate record
; reconstruction
; silica
; Baffin Island
; Canada
; Canadian Arctic
; Labrador
; Newfoundland and Labrador
; Nunavut
; Penny Ice Cap
; Quebec [Canada]
; Bacillariophyta
英文摘要: Nettilling Lake is located on Baffin Island, Nunavut, Canada between the areas of past warming (Canadian High Arctic to the North) and climatic stability (Northern Quebec and Labrador region to the South). Despite being the largest lake in the Nunavut region with a postglacial marine to lacustrine transition history only a few paleo-environmental investigations were completed in this area. The oxygen isotope composition of diatoms (δ18Odiatom) can provide valuable insights into paleo-environmental conditions. Here, the recent (isotope) hydrology and hydrochemical data from the lake are presented to facilitate the interpretation of a δ18Odiatom record from an 82 cm sediment core (Ni-2B). The well-mixed lake (δ18Owater = −17.4‰) is influenced by a heavier (less negative) isotope composition (−18.80‰) from Amadjuak River draining Amadjuak Lake to the South and water of lighter (more negative) isotopic composition (−16.4‰) from the Isurtuq River originating from Penny Ice Cap in the North-East. From the δ18Owater and δ18Odiatom of the topmost sample of core Ni-2B a Δ18Osilica-water of 1000 ln α(silica-water) = 40.2‰ for sub-recent diatoms of Nettilling Lake was calculated matching the known water-silica fractionation for fossil sediments well and thereby showing the general applicability of this proxy for paleo-reconstructions in this region. Extremely large δ18Odiatom variations in the core of more than 13‰ are mainly induced by changes in the isotopic composition of the lake water due to a shift from glaciomarine (δ18Odiatom = +34.6‰) through brackish (+23.4 to +27.2‰) towards lacustrine (+21.5‰) conditions (transition zones glaciomarine to brackish at 69 cm/7300 yr cal. BP and brackish to lacustrine at 35 cm/6000 yr cal. BP) associated with a shift in the degree of salinity. Our study provides the first evidence that paleo-salinity can be reconstructed by δ18Odiatom. Additionally, for the lacustrine section it could be demonstrated that δ18Odiatom may serve as a proxy for past air temperature within the same core recording a late Holocene cooling of about 4 °C being consistent with other published values for the greater Baffin region. © 2016 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59497
Appears in Collections: 过去全球变化的重建
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作者单位: Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Research Unit Potsdam, Telegrafenberg A43, Potsdam, Germany; Laboratoire de Paléoécologie Aquatique, Centre d'études nordiques & Département de géographie, Université LavalQC, Canada
Recommended Citation:
Chapligin B.,Narancic B.,Meyer H.,et al. Paleo-environmental gateways in the eastern Canadian arctic – Recent isotope hydrology and diatom oxygen isotopes from Nettilling Lake, Baffin Island, Canada[J]. Quaternary Science Reviews,2016-01-01,147