A tree of Indo-African mantle plumes imaged by seismic tomography
A tree of Indo-African mantle plumes imaged by seismic tomography
复制标题
地震层析成像成像的印度-非洲地幔柱树
作者：
Maria Tsekhmistrenko;K. Sigloch;Kasra Hosseini;G. Barruol
地幔柱被认为是薄而垂直的管道，来自最下层地幔的浮热岩石在其中上升到地球表面，表现为远离板块边界的热点型火山活动。在空间上与热点相关的是最下地幔中两个巨大的慢速地震波传播区，可能代表了为羽流提供能量的热库。事实证明，对羽流管道进行成像很困难，因为大多数羽流管道位于未仪器化的海洋下方，而且可能很薄。在这里，我们结合新的地震数据集来解决以非洲、印度洋和南大洋为中心的所有深度和长度尺度的地幔上升流问题。利用对最深地幔进行广泛采样的地震波，我们发现地幔上升流呈树状结构排列。从深度约 1,500 公里以下的中央紧凑树干开始，三个分支向外和向上倾斜，朝向各个印度-澳大利亚热点地区。我们提出，每个倾斜分支代表垂直上升的斑点或原始羽流的排列，它们以线性交错序列从其位于核心-地幔边界的底层低速走廊中分离出来。一旦斑点达到下地幔和上地幔之间的粘度不连续性，它就会产生“经典”的羽头/羽尾序列。根据地震层析成像，印度-非洲地幔上升流排列成树状结构，这可能反映了原始地幔柱与最下地幔的线性交错分离。
Mantle plumes were conceived as thin, vertical conduits in which buoyant, hot rock from the lowermost mantle rises to Earth’s surface, manifesting as hotspot-type volcanism far from plate boundaries. Spatially correlated with hotspots are two vast provinces of slow seismic wave propagation in the lowermost mantle, probably representing the heat reservoirs that feed plumes. Imaging plume conduits has proved difficult because most are located beneath the non-instrumented oceans, and they may be thin. Here we combine new seismological datasets to resolve mantle upwelling across all depths and length scales, centred on Africa and the Indian and Southern oceans. Using seismic waves that sample the deepest mantle extensively, we show that mantle upwellings are arranged in a tree-like structure. From a central, compact trunk below ~1,500 km depth, three branches tilt outwards and up towards various Indo-Austral hotspots. We propose that each tilting branch represents an alignment of vertically rising blobs or proto-plumes, which detached in a linear staggered sequence from their underlying low-velocity corridor at the core–mantle boundary. Once a blob reaches the viscosity discontinuity between lower and upper mantle, it spawns a ‘classical’ plume-head/plume-tail sequence. Indo-African mantle upwellings are arranged in a tree-like structure, which might reflect linear staggered detachment of proto-plumes from the lowermost mantle, according to seismic tomographic imaging.
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通过非常规应用浮动地震仪对加拉帕戈斯地幔柱进行成像
影响因子：
4.6
作者：
Nolet, Guust;Hello, Yann;Lee, Suzan van;Bonnieux, Sébastien;Ruiz, Mario C.;Pazmino, Nelson A.;Deschamps, Anne;Regnier, Marc M.;Font, Yvonne;Chen, Yongshun J.
通讯作者：
Chen, Yongshun J.
影响因子：
5.3
作者：
Jackson, M. G.;Becker, T. W.;Konter, J. G.
通讯作者：
Konter, J. G.
影响因子：
2.8
作者：
Hosseini, Kasra;Sigloch, Karin;Igel, Heiner
通讯作者：
Igel, Heiner
DOI：
10.1029/2018gc007431
发表时间：
2018-05
期刊：
Geochemistry, geophysics, geosystems : G(3)
影响因子：
--
作者：
Hosseini K;Matthews KJ;Sigloch K;Shephard GE;Domeier M;Tsekhmistrenko M
通讯作者：
Tsekhmistrenko M
从接收函数和环境噪声相关性看马达加斯加南部的地壳结构：对地壳演化的影响
DOI：
10.1002/2016jb013565
发表时间：
2017
期刊：
Journal of Geophysical Research: Solid Earth
影响因子：
--
作者：
Rindraharisaona;Tilmann;Rümpker;Rambolamanana;Barruol
通讯作者：
Barruol