DOI: 10.1016/j.gloplacha.2016.11.004
论文题名: Benthic foraminiferal assemblages and bottom water evolution off the Portuguese margin since the Middle Pleistocene
作者: Guo Q. ; Li B. ; Kim J.-K.
刊名: Global and Planetary Change
ISSN: 0921-8181
出版年: 2017
卷: 150 起始页码: 94
结束页码: 108
语种: 英语
英文关键词: Benthic foraminifera
; Mediterranean outflow water
; Middle-Late Pleistocene
; Portuguese margin
Scopus关键词: Cluster analysis
; Glacial geology
; Sea level
; Benthic foraminifera
; Foraminiferal assemblages
; Glacial-interglacial cycles
; Hydrodynamic conditions
; Late Pleistocene
; Mediterranean outflow waters
; Northeast Atlantic Ocean
; Portuguese margin
; Aquatic organisms
英文摘要: The upper 250 meter-long sediment core of Site U1391 (1085 m water depth) retrieved from the Portuguese margin in the Northeast Atlantic Ocean was adopted for the benthic foraminiferal analyses to disclose the variations in Mediterranean Outflow Water (MOW) intensity over the last ~ 0.9 Ma. Benthic foraminifera are abundant at this site and mainly composed of the hyaline forms (80%, such as Cibicidoides/Cibicides spp., Globobulimina spp., Bulimina spp., Uvigerina spp., Melonis spp., Sphaeroidina bulloides, Hoeglundina elegans, Gyroidinoides spp., Lenticulina spp. and Planulina ariminensis), while the agglutinated and porcelaneous forms have only 5% and 14.1% on average, respectively. Down-core variations of the benthic foraminifera show glacial-interglacial contrasts, especially those of Lenticulina spp. and Planulina ariminensis, which is also supported by the benthic foraminiferal cluster analysis. During the interglacial periods, the fauna are dominated by Sphaeroidina bulloides, Lenticulina spp., Planulina ariminensis, Dentalina spp., Cibicidoides robertsonianus and the agglutinated forms, while by Cibicidoides pachyderma, Praeglobobulimina ovata, Praeglobobulimina pupoides, Bulimina mexicana, Uvigerina mediterranea, Bolivinita quadrilatera and mililoids during the glacial periods. Benthic foraminiferal faunal data at Site U1391 was detailed analyzed to disclose the bottom water property over the last ~ 0.9 Ma. Variations of the character species or assemblages, such as Planulina ariminensis, and the “elevated epibenthos” group suggest that the MOW intensity has typical glacial-interglacial cycles, strengthening during the interglacial periods and weakening during the glacial periods, and reaches its peak at MIS 11. The strongest MOW intensity during MIS 11 confirms the climatic influence of waving sea level on the MOW current by its + 20 m high-stand above the present sea level. The agglutinated benthic foraminifera have a significantly positive correlation with the MOW index of “elevated epibenthos”, which suggests that their abundance can be used to monitor the hydrodynamic conditions of bottom water off the Portuguese margin. Consistent with the MOW intensity, the lower miliolids content implies a lower salinity which supported the stronger vertical density gradient during the interglacial periods in this region; while the glacial ocean has a higher salinity with a weak vertical density gradient/MOW intensity. © 2016 Elsevier B.V. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85009471470&doi=10.1016%2fj.gloplacha.2016.11.004&partnerID=40&md5=8d9c22c42b8864f37bbcd54c85bf5916
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/11751
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: Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, China
Recommended Citation:
Guo Q.,Li B.,Kim J.-K.. Benthic foraminiferal assemblages and bottom water evolution off the Portuguese margin since the Middle Pleistocene[J]. Global and Planetary Change,2017-01-01,150.