Two anisotropic layers in central orogenic belt of North China Craton
Two anisotropic layers in central orogenic belt of North China Craton
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DOI：
10.1016/j.tecto.2010.09.002
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发表时间：
2010-10
期刊：
影响因子：
2.9
通讯作者：
L. Bai;H. Kawakatsu;Y. Morita
中科院分区：
文献类型：
--
作者：
L. Bai;H. Kawakatsu;Y. Morita
本文利用双折射剪切波分裂分析，证明了华北造山带中央造山带上地幔存在两层各向异性。一个单层模型是在中央造山带台站的约束好的方位角依赖分裂参数不一致，但是，两层的各向异性提高了数据的拟合。在底层，快速极化方向是平行于绝对板块运动，表明目前的应变存在于亚磁软流圈与周围板块之间的相互作用。相比之下，在顶层，快极化方向与当地地表断层的走向一致，证实了岩石圈过去造山运动的综合贡献。
We present evidence of two layers of anisotropy in Earth's upper mantle beneath the central orogenic belt of the North China Craton from teleseismic shear-wave splitting analysis. A one-layer model is in disagreement with the well-constrained azimuth-dependent splitting parameters for stations in the central orogenic belt; however, two layers of anisotropy improve the fit to the data. At the bottom layer, the fast polarization directions are subparallel to the absolute plate motion, indicating the presence of the current strain within the subcratonic asthenosphere related to the interactions between the surrounding plates. In contrast, at the top layer, the fast polarization directions are consistent with the strikes of the local surface faults, confirming a combined contribution of the past orogenies in the lithosphere.