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深源地震揭秘上地幔的性质 快报文章
地球科学快报，2023年第05期
作者:  王晓晨
Microsoft Word(15Kb)  |  收藏  |  浏览/下载：690/0  |  提交时间：2023/03/10
deep earthquake  upper-mantle  
研究表明深地幔具有新的矿物学特征 快报文章
地球科学快报，2022年第21期
作者:  王晓晨
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deep mantle  bridgmanite  
新研究称地球生命的发展影响了地球下地幔 快报文章
地球科学快报，2022年第07期
作者:  刘文浩
Microsoft Word(16Kb)  |  收藏  |  浏览/下载：745/0  |  提交时间：2022/04/08
Cambrian Explosion  deep-Earth carbon cycle  mantle  
Hydrothermal (NN)-N-15-N-15 abundances constrain the origins of mantle nitrogen 期刊论文
NATURE, 2020, 580 (7803) : 367-+
作者:  Zhao, Steven;  Jang, Cholsoon;  Liu, Joyce;  Uehara, Kahealani;  Gilbert, Michael;  Izzo, Luke;  Zeng, Xianfeng;  Trefely, Sophie;  Fernandez, Sully;  Carrer, Alessandro;  Miller, Katelyn D.;  Schug, Zachary T.;  Snyder, Nathaniel W.;  Gade, Terence P.;  Titchenell, Paul M.;  Rabinowitz, Joshua D.;  Wellen, Kathryn E.
收藏  |  浏览/下载：35/0  |  提交时间：2020/05/13

Nitrogen is the main constituent of the Earth'  s atmosphere, but its provenance in the Earth'  s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth'  s accretion versus that subducted from the Earth'  s surface is unclear(1-6). Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare (NN)-N-15-N-15 isotopologue of N-2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle delta N-15 (the fractional difference in N-15/N-14 from air), N-2/Ar-36 and N-2/He-3. Our results show that negative delta N-15 values observed in gases, previously regarded as indicating a mantle origin for nitrogen(7-10), in fact represent dominantly air-derived N-2 that experienced N-15/N-14 fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the (NN)-N-15-N-15 data allow extrapolations that characterize mantle endmember delta N-15, N-2/Ar-36 and N-2/He-3 values. We show that the Eifel region has slightly increased delta N-15 and N-2/Ar-36 values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts(11), consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has delta N-15 values substantially greater than that of the convective mantle, resembling surface components(12-15), its N-2/Ar-36 and N-2/He-3 ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume delta N-15 values may both be dominantly primordial features.


  
Metastable Olivine Wedge Beneath the Japan Sea Imaged by Seismic Interferometry 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (6)
作者:  Shen, Zhichao;  Zhan, Zhongwen
收藏  |  浏览/下载：19/0  |  提交时间：2020/07/02
metastable olivine  inter-source interferometry  deep earthquake mechanism  dry slab core  mantle transition zone  
Metallic iron limits silicate hydration in Earth’s transition zone 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2019, 116 (45) : 22526-22530
作者:  Feng Zhu;  Jie Li;  Jiachao Liu;  Junjie Dong;  and Zhenxian Liu
收藏  |  浏览/下载：13/0  |  提交时间：2019/11/27
mantle transition zone  water budget  redox reaction  mantle oxidation state  deep hydrogen cycle  
Predicting Rates and Distribution of Carbonate Melting in Oceanic Upper Mantle: Implications for Seismic Structure and Global Carbon Cycling 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2018, 45 (14) : 6944-6953
作者:  Clerc, Fiona;  Behn, Mark D.;  Parmentier, E. M.;  Hirth, Greg
收藏  |  浏览/下载：13/0  |  提交时间：2019/04/09
carbonate melt  Gutenberg discontinuity  oceanic upper mantle  lithosphere-asthenosphere boundary  deep carbon cycle  
Discovery of a hexagonal ultradense hydrous phase in (Fe,Al)OOH 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2018, 115 (12) : 2908-2911
作者:  Zhang, Li;  Yuan, Hongsheng;  Meng, Yue;  Mao, Ho-Kwang
收藏  |  浏览/下载：22/0  |  提交时间：2019/11/27
X-ray diffraction  hydrous mineral  lower mantle  deep-water cycle