...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Paleoceanography >North Atlantic Upper-Ocean Hydrography During the Mid-Pleistocene Transition Evidenced by Globorotalia truncatulinoides Coiling Ratios
【24h】

North Atlantic Upper-Ocean Hydrography During the Mid-Pleistocene Transition Evidenced by Globorotalia truncatulinoides Coiling Ratios

机译：北大西洋上海水文中的中间海洋过渡期，由Globoralatia truncatulinoides卷曲比证明

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We use the coiling direction of planktic foraminifer Globorotalia truncatulinoides from four sites in the North Atlantic Ocean to assess spatial changes in upper-ocean hydrography during the mid-Pleistocene climate transition. Core top sediments indicate that the left-coiling (sinistral) variety dominates regions characterized by a deep permanent thermocline as is characteristic of the subtropical gyre (Ocean Drilling Program Sites 1058 and Deep Sea Drilling Project Site 607) while right-coiling (dextral) tests dominate the tropical (Ocean Drilling Program Site 925) and subpolar site (Deep Sea Drilling Project Site 552). We observe pronounced changes in the dominant coiling direction at the three subtropical to subpolar sites during the first of the more extreme glacial to interglacial transitions of the mid-Pleistocene climate transition, Marine Isotope Stages (MISs) 22 to 21. We interpret these observations to reflect an increase in poleward warm water advection. The time interval between MIS 21 and MIS 15 is marked by a pronounced absence of sinistral tests. Because G. truncatulinoides (sinistral) is a deep dwelling species, their absence may be related to a decrease in dissolved oxygen during warm interglacial intervals. At the tropical site, precessional-scale variations dominate changes in the coiling direction until midpoint interglacial MIS 23. Occurrences in the sinistral variety at this locale must be linked to cross-equatorial water transport in the North Brazil Current, and precessional-scale variations provide evidence for the sensitivity of the tropical regions to precessional forcing, at least until MIS 23 when this morphotype disappears in agreement with observation at other sites in the Atlantic Ocean.
机译：我们使用北大西洋四个地点的塑料Flobinifer GloborotaliOnoides的卷绕方向从北大西洋的四个地点评估中间人气候过渡期间海洋水处理的空间变化。核心顶部沉积物表明，左侧卷绕（SINISTRAL）品种主要主导地区，其特征在于亚热带孢子（海洋钻井计划站点1058和深海钻井项目部位607）的亚热带孢子（海洋钻井计划站点1058和深海钻井项目部位607）的特征。主导热带（海洋钻井计划网站925）和亚极钻井场所（深海钻井项目现场552）。我们在第一个更极端冰川到中间胞酮气候转型的中间冰激地位的第一个更极端的冰川地区观察到三个亚热带的显着变化的变化，海洋同位素阶段（Miss）22至21的中间峡层过渡。我们解释了这些观察反映了极向温水的增加。 MIS 21和MIS 15之间的时间间隔由发音缺乏索列误导。因为G. truncatulinoides（Sinistral）是一种深入的住所物种，因此它们的缺乏可能与暖冰间隔期间的溶解氧的减少有关。在热带场地，预定级别变化在卷取方向上占据了变化，直到中点屏幕MES 23。此区域环境中的初始品种的发生必须与北巴西电流的跨赤道水运输相关，并提供预级别的水分差异热带地区对前期强迫的敏感性的证据，至少直到MIS 23，当这种Morphot型在达到大西洋中其他网站的观察时消失。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号