• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nature >Evidence for the survival of the oldest terrestrial mantle reservoir
【24h】

Evidence for the survival of the oldest terrestrial mantle reservoir

机译：最古老的地幔储层生存的证据

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

Helium is a powerful tracer of primitive material in Earth's mantle. Extremely high ~3He/~4He ratios in some ocean-island basalts suggest the presence of relatively undegassed and undifferentiated material preserved in Earth's mantle. However, terrestrial lavas with high ~3He/~4He ratios have never been observed to host the primitive lead-isotopic compositions that are required for an early (roughly 4.5 Gyr ago) formation age. Here we show that Cenozoic-era Baffin Island and West Greenland lavas, previously found to host the highest terrestrial-mantle ~3He/~4He ratios, exhibit primitive lead-isotope ratios that are consistent with an ancient mantle source age of 4.55-4.45 Gyr. The Baffin Island and West Greenland lavas also exhibit ~(143)Nd/~(144)Nd ratios similar to values recently proposed for an early-formed (roughly 4.5 Gyr ago) terrestrial mantle reservoir. The combined helium-, lead- and Nd-isotopic compositions in Baffin Island and West Greenland lavas therefore suggest that their source is the most ancient accessible reservoir in the Earth's mantle, and it may be parental to all mantle reservoirs that give rise to modern volcanism.
机译：氦是地球地幔中原始物质的有力示踪剂。在某些海洋岛的玄武岩中，〜3He /〜4He的比率极高，这表明地球地幔中保存着相对未脱色和未分化的物质。然而，从未观察到具有高〜3He /〜4He比的陆地熔岩具有早期（大约4.5 Gyr以前）地层时代所需的原始铅同位素组成。在这里，我们显示了以前发现的地幔〜3He /〜4He比例最高的新生代巴芬岛熔岩和西格陵兰熔岩表现出的原始铅-同位素比值与4.55-4.45 Gyr的古代地幔源年龄一致。巴芬岛和西格陵兰岛的熔岩也表现出〜（143）Nd /〜（144）Nd的比率，与最近为早期形成的（约4.5吉尔）地幔储层提出的值相似。因此，巴芬岛和西格陵兰熔岩中氦，铅和钕同位素的组合成分表明，它们的来源是地球地幔中最古老的可及储层，并且可能是所有引起现代火山活动的地幔储层的源头。

著录项

  • 来源
    《Nature》 |2010年第7308期|P.853-856ⅲ|共5页
  • 作者

    Matthew G. Jackson; Richard W. Carlson; Mark D. Kurz; Pamela D. Kempton; Don Francis; Jerzy Blusztajn;

  • 作者单位

    Department of Earth Sciences, Boston University, 675 Commonwealth Avenue, Boston, Massachusetts 02215, USA Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington DC 20015, USA;

    rnDepartment of Terrestrial Magnetism, Carnegie Institution of Washington, Washington DC 20015, USA;

    rnDepartment of Marine Chemistry, Woods Hole Oceanographic Institution, 266 Woods Hole Road, Woods Hole, Massachusetts 02543,USA;

    rnNatural Environment Research Council (NERO, Polaris House, North Star Avenue, Swindon SN2 1EU, UK;

    rnEarth and Planetary Sciences, McGill University, 3450 University Street, Montreal, Quebec H3A 2A7, Canada;

    rnDepartment of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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