期刊
EARTH AND PLANETARY SCIENCE LETTERS
卷 293, 期 3-4, 页码 269-276出版社
ELSEVIER
DOI: 10.1016/j.epsl.2010.02.041
关键词
deep sea corals; Delta C-14; Heinrich events; Mystery Interval; ocean circulation; ocean ventilation
Simultaneous C-14 and Th/U dating of deep sea corals are useful for reconstructing the intensity of deep ocean circulation in the past, as they deliver the time between the gas exchange of the water with the atmosphere and the incorporation of the C-14 in the carbonates (Adkins and Boyle, 1997; Adkins et al., 1998; Mangini et al., 1998). Th/U ages of deep sea corals sampled in sediment cores from locations off the coast of Brazil bathed by Antarctic Intermediate Water at depths between 600 and 800 m group close to Heinrich events H2, H1 and the Younger Dryas. The Delta C-14 of the water bathing the corals starts to decrease approximately 2 kyr before the Heinrich events and decreases to values 400% lower than the corresponding back tracked atmospheric values. The timing and the magnitude of the decrease is similar to that observed in intermediate water in the N. Pacific off Baja California (Marchitto et al., 2007) and in the Eastern Pacific (Stott et al., 2009). High ventilation ages, partly exceeding 4000 years, are an unambiguous indication for a reduction of North Atlantic deep water formation during H2, H1 and the YD, as deduced from higher Pa-231/Th-230 activity ratios and from epsilon Nd in N. Atlantic Ocean sediments (McManus et al., 2004; Pahnke et al., 2008; Yu et al., 1996). They also could indicate a poorly oxygenated Southern Pacific Ocean at the end of the Heinrich events. (C) 2010 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据