DOI: 10.1016/j.gloplacha.2015.06.002
论文题名: A micropalaeontological perspective on export productivity, oxygenation and temperature in NE Atlantic deep-waters across Terminations I and II
作者: Grunert P. ; Skinner L. ; Hodell D.A. ; Piller W.E.
刊名: Global and Planetary Change
ISSN: 0921-8181
出版年: 2015
卷: 131 起始页码: 174
结束页码: 191
语种: 英语
英文关键词: Benthic foraminifera
; Glacial terminations
; Iberian margin
; IODP Site U1385
; Multiproxy records
; Taphonomy
Scopus关键词: Biogeochemistry
; Biological materials
; Carbon
; Glacial geology
; Isotopes
; Organic compounds
; Oxygenation
; Benthic foraminifera
; Glacial terminations
; Iberian margin
; IODP Site U1385
; Multiproxy records
; Taphonomy
; Oceanography
; benthic foraminifera
; fossil assemblage
; interglacial
; micropaleontology
; oxygenation
; paleoenvironment
; paleoproductivity
; sea surface temperature
; taphonomy
; water mass
; Atlantic Ocean
; Iberian Margin
; Foraminifera
英文摘要: Census counts of benthic foraminifera were studied from the SW Iberian Margin to reconstruct past changes in deep-water hydrography across Terminations I and II. Detailed benthic faunal data (>. 125. μm size-fraction) allow us to evaluate the limitations imposed by taphonomic processes and restricted size-fractions. The comparison of recent (mudline) and fossil assemblages at IODP Site U1385 indicates the quick post-mortem disintegration of shells of astrorhizoid taxa (~. 80% of the present-day fauna), resulting in impoverished fossil assemblages. While the application of quantitative proxy methods is problematic under these circumstances, the fossil assemblages can still provide a qualitative palaeoenvironmental signal that, while most fully expressed in the 125-212. μm size-fraction, is nonetheless also expressed to some degree in the >. 212. μm size-fraction.Variations in the benthic foraminiferal assemblages reveal information about changing organic matter supply, deep-water oxygenation and temperature. MIS 2 is generally characterized by an elevated trophic state and variable oxic conditions, with oxygenation minima culminating in the Younger Dryas (YD) and Heinrich Stadials (HS) 1, 2 and 3. Low oxic conditions coincide with decreased water-temperature and lower benthic δ13C, pointing to the strong influence of a southern sourced water-mass during these periods. HS 1 is the most extreme of these intervals, providing further evidence for a severe temporary reduction or even shutdown of AMOC. With the inception of MIS 1, organic matter supply reduced and a better ventilated deep-water environment bathed by NEADW is established.For Termination II, clear indications of southern-sourced water are limited to the early phase of HS 11. During the latter part of HS 11, the deep-water environment seems to be determined by strongly increased supply of organic matter, potentially explaining the decoupling of benthic δ13C and Mg/Ca records of earlier studies as a phytodetritus effect on the carbon isotope signal. However, the presence of a warm, nutrient-rich and poorly oxygenated water-mass cannot be ruled out. With the inception of interglacial MIS 5e trophic conditions are reduced and ventilation by NEADW increases © 2015. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84931271499&doi=10.1016%2fj.gloplacha.2015.06.002&partnerID=40&md5=0a25518562bfc83224603b6fa7a30e0c
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/11508
Appears in Collections: 全球变化的国际研究计划 气候变化与战略
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作者单位: Department of Earth and Planetary Sciences, Rutgers University, 610 Taylor Road, Piscataway, NJ, United States
Recommended Citation:
Grunert P.,Skinner L.,Hodell D.A.,et al. A micropalaeontological perspective on export productivity, oxygenation and temperature in NE Atlantic deep-waters across Terminations I and II[J]. Global and Planetary Change,2015-01-01,131.