• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chinese science bulletin >Nd isotope as the tracer of seawater evolution of early Miocene in the eastern Pacific Ocean
【24h】

Nd isotope as the tracer of seawater evolution of early Miocene in the eastern Pacific Ocean

机译：钕同位素作为东太平洋中新世早期海水演化的示踪剂

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

Fifty-six samples of nannofossil ooze were collected from Core PC5794 in the northern equatorial Pacific at 5 cm intervals. With the methods of mass spectrometer (VG354) and ICP, the Nd isotopic compositions (ε_(Nd)(t)), Mn contents and Mg/Sr ratios of carbonate phase have been analyzed. CaCO_3 contents of bulk sediments were obtained by dissolution of 0.5 mol/L HCl. Based on these data, the high-resolution ε_(Nd)(t) profile of seawater in early Miocene with core depth(or time) have been established. The values of ε_(Nd)(t) range from — 6.2 to — 2.97 and 4 fluctuation cycles existed during 24.06 — 22.02 Ma. 4 low ε_(Nd)(t) values (about -6.4) correspond to high CaCO_3 contents, which implicates that there were 4 cold epochs or 4 times of Antarctic Bottom Water activity. They occurred at the time of 24.06 Ma, 23.85 Ma, 22.88 Ma and 22.26 Ma, respectively. High ε_(Nd)(t) values correspond to the high Mn contents and high values of Mg/Sr ratio, which indicates the existence of 4 intense hydrothermal activity periods during 24.06 — 22 Ma, the durations of them are 4.05 — 23.98 Ma, 23.69 — 23.15 Ma, 22.74 — 22.37 Ma and 22.06 — 22.02 Ma, respectively.
机译：从北赤道太平洋的PC5794核心以5 cm的间隔收集了56个纳米化石软泥样品。用质谱仪（VG354）和ICP法分析了Nd同位素组成（ε_（Nd）（t）），Mn含量和碳酸盐相的Mg / Sr比。通过溶解0.5 mol / L HCl获得大体积沉积物中CaCO_3的含量。基于这些数据，建立了中新世早期具有岩心深度（或时间）的高分辨率ε_（Nd）（t）剖面。 ε_（Nd）（t）的值在6.2至2.97之间，并且在24.06-22.02 Ma内存在4个波动周期。 4个较低的ε_（Nd）（t）值（约-6.4）对应于较高的CaCO_3含量，这意味着有4个寒冷时期或南极底水活动的4倍。它们分别在24.06 Ma，23.85 Ma，22.88 Ma和22.26 Ma发生。较高的ε_（Nd）（t）值对应较高的Mn含量和较高的Mg / Sr比值，这表明在24.06-22 Ma内存在4个强烈的热液活动周期，持续时间为4.05-23.98 Ma，分别为23.69-23.15 Ma，22.74-22.37 Ma和22.06-22.02 Ma。

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