Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1002/2017GL073120 |
Signals of 660 km topography and harzburgite enrichment in seismic images of whole-mantle upwellings | |
Maguire, Ross1; Ritsema, Jeroen1; Goes, Saskia2 | |
2017-04-28 | |
发表期刊 | GEOPHYSICAL RESEARCH LETTERS |
ISSN | 0094-8276 |
EISSN | 1944-8007 |
出版年 | 2017 |
卷号 | 44期号:8 |
文章类型 | Article |
语种 | 英语 |
国家 | USA; England |
英文摘要 | Various changes in seismic structures across the mantle transition zone (MTZ) indicate that it may hamper thermal and chemical circulation. Here we show how thermal elevation of the postspinel phase transition at 660 km depth plus harzburgite segregation below this depth can project as narrow high-velocity anomalies in tomographic images of continuous thermochemical mantle upwellings. Model S40RTS features a narrow high-velocity anomaly of +0.8% near 660 km depth within the broad low-velocity structure beneath the Samoa hot spot. Our analyses indicate that elevation of the 660 phase boundary in a hot pyrolitic plume alone is insufficient to explain this anomaly. An additional effect of harzburgite enrichment is required and consistent with geodynamic simulations that predict compositional segregation in the MTZ, especially within thermochemical upwellings. The Samoa anomaly can be modeled with a 125-175 degrees C excess temperature and a harzburgite enrichment below 660 of least 60% compared to a pyrolitic mantle. |
领域 | 气候变化 |
收录类别 | SCI-E |
WOS记录号 | WOS:000401847500020 |
WOS关键词 | KM DISCONTINUITY ; STRUCTURE BENEATH ; PHASE-EQUILIBRIA ; SHEAR-VELOCITY ; TRANSITION ; PLUMES ; MODELS ; AMERICA |
WOS类目 | Geosciences, Multidisciplinary |
WOS研究方向 | Geology |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/25999 |
专题 | 气候变化 |
作者单位 | 1.Univ Michigan, Dept Earth & Environm Sci, Ann Arbor, MI 48109 USA; 2.Imperial Coll London, Dept Earth Sci & Engn, London, England |
推荐引用方式 GB/T 7714 | Maguire, Ross,Ritsema, Jeroen,Goes, Saskia. Signals of 660 km topography and harzburgite enrichment in seismic images of whole-mantle upwellings[J]. GEOPHYSICAL RESEARCH LETTERS,2017,44(8). |
APA | Maguire, Ross,Ritsema, Jeroen,&Goes, Saskia.(2017).Signals of 660 km topography and harzburgite enrichment in seismic images of whole-mantle upwellings.GEOPHYSICAL RESEARCH LETTERS,44(8). |
MLA | Maguire, Ross,et al."Signals of 660 km topography and harzburgite enrichment in seismic images of whole-mantle upwellings".GEOPHYSICAL RESEARCH LETTERS 44.8(2017). |
条目包含的文件 | 条目无相关文件。 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论