Mid-mantle heterogeneities associated with Izanagi plate: Implications for regional mantle viscosity
Mid-mantle heterogeneities associated with Izanagi plate: Implications for regional mantle viscosity
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与伊邪那岐板块相关的中地幔异质性：对区域地幔粘度的影响
DOI：
10.1016/j.epsl.2013.10.042
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发表时间：
2014
影响因子：
5.3
通讯作者：
李娟
中科院分区：
文献类型：
--
作者：
李娟
我们使用S到P转换波形检测中国东北和邻近的日本海下的中地幔散射。利用非线性台阵叠加技术分析了8次中深源地震的宽频带短周期波形，清晰地揭示了930-1120 km深度范围内的中地幔散射体。这些不均匀体的总体横向范围为1800 km，大多发生在高速异常区域内。在中地幔深处的MORB类板状物质的积累可能会导致不同的化学成分比周围的橄榄岩地幔。从停滞的太平洋板块的不均匀性的空间隔离表明有关的古Izanagi板块俯冲的起源。结合重建的板块运动历史，估算了下地幔顶部的粘度值为1.0× 1022 ~ 1.6× 1023 Pa·s，可作为区域尺度下地幔流变学的独立约束。
We employed S-to-P converted waveforms to detect mid-mantle scattering beneath northeastern China and the adjacent Japan Sea. Broadband and short-period waveforms recorded by seismic arrays for eight moderate-sized deep earthquakes were analyzed using a non-linear array stacking technique, and mid-mantle scatterers within the depth range 930–1120 km were clearly revealed. The heterogeneities have an overall lateral extent of∼ 800 km, and mostly occur within a region with a high velocity anomaly. The accumulation of MORB-like slab materials at mid-mantle depths might cause a different chemical composition than that of the surrounding peridotitic mantle. The spatial isolation of the heterogeneities from the stagnant Pacific slab suggests an origin related to the subduction of ancient Izanagi plate. In combination with the reconstruction history of plate motions, we estimate the viscosity of the topmost lower mantle to vary from 1.0× 10 22 to 1.6× 10 23 Pa s, which can be used as an independent constraint on the rheology of the lower mantle on a regional scale.
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影响因子：
3
作者：
E. Engdahl;R. Hilst;R. Buland
通讯作者：
E. Engdahl;R. Hilst;R. Buland
影响因子：
--
作者：
S. Kaneshima;G. Helffrich
通讯作者：
S. Kaneshima;G. Helffrich
影响因子：
2.8
作者：
KENNETT, BLN;ENGDAHL, ER
通讯作者：
ENGDAHL, ER
影响因子：
56.9
作者：
Yves LeStunff;C. Wicks;B. Romanowicz
通讯作者：
Yves LeStunff;C. Wicks;B. Romanowicz
影响因子：
5.3
作者：
Capitanio, F. A.;Morra, G.;Goes, S.
通讯作者：
Goes, S.