Broadscale interseismic deformation and fault slip rates in the central Tibetan Plateau observed using InSAR
Broadscale interseismic deformation and fault slip rates in the central Tibetan Plateau observed using InSAR
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InSAR观测青藏高原中部大尺度震间形变和断层滑动速率
DOI：
10.1002/jgrb.50348
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发表时间：
2013-09
影响因子：
--
通讯作者：
Wright, T. J.
中科院分区：
文献类型：
--
作者：
Garthwaite, M. C.;Wang, H.;Wright, T. J.
了解地壳断层的数量、位置和震间滑动速率是我们理解大陆变形整体力学的关键。然而，目前，大地速度观测的稀疏性是一个主要的限制因素，以提高我们的断层网络的知识。在这项研究中，我们结合联合收割机长测绘带干涉合成孔径雷达（干涉合成孔径雷达）数据，形成一个跨越青藏高原中部超过1000公里长的地震间位移速率图。我们密集的大地测量观测表明，应变在空间上变化平稳，而没有主要集中在以前绘制的断层。在33°N-35°N之间，视线干涉合成孔径雷达和GPS观测值之间的差异可能表明该地区的地表隆起约为4 mm/年。整个高原的应变率小于5 × 10−8 yr−1。在东西向左昆仑断层，2001年可可西里地震后的震后变形导致在100 km宽的区域内观测到18 ± 4 × 10−8 yr−1的应变率。在去除粘弹性模型后，我们估计昆仑断层的震间滑动速率为12 ± 2 mm/年。在西藏中部共轭断裂带中，NE-SW走向的Amdo-Sewa和NW-SE走向的Beng Co断层的右旋滑动速率分别为6 ± 1 mm/yr和1-4 ± 1 mm/yr。与此同时，东北-西南走向的东桥断层的左行滑动速率为1-2 ± 1 mm/yr。我们估计这些故障的低滑动率表明，构造应变更广泛地分布在整个高原内部，可能是由于岩石圈是弱的，没有突然的强度对比，存在于高原边缘。
Knowledge of the number, location, and interseismic slip rate of crustal faults is key to our understanding of the bulk mechanics of continental deformation. However, at present, the sparsity of geodetic velocity observations is a major limiting factor to improving our knowledge of the fault network. In this study, we combine long‐swath interferometric synthetic aperture radar (InSAR) data to form an interseismic displacement rate map of over 1000 km length spanning the central Tibetan Plateau. Our dense geodetic observations indicate that strain varies smoothly in space without major concentration at previously mapped faults. Discrepancy between line‐of‐sight InSAR and GPS observations between 33°N–35°N could indicate ~4 mm/yr of surface uplift in this region. Derived strain rates are less than 5 × 10−8 yr−1 across the plateau. At the E‐W left‐lateral Kunlun fault, postseismic deformation following the 2001 Kokoxili earthquake results in an observed strain rate of 18 ± 4 × 10−8 yr−1 across a 100 km wide zone. Following removal of a viscoelastic model, we estimate an interseismic slip rate of 12 ± 2 mm/yr for the Kunlun fault. In the central Tibetan conjugate fault zone, the NE‐SW striking Amdo‐Sewa and NW‐SE striking Beng Co faults have right‐lateral slip rates of 6 ± 1 mm/yr and 1–4 ± 1 mm/yr, respectively. Meanwhile, the NE‐SW striking Dongqiao fault has a left‐lateral slip rate of 1–2 ± 1 mm/yr. The low slip rates we estimate for these faults indicate that tectonic strain is more broadly distributed across the plateau interior, perhaps due to the lithosphere being weak and without the abrupt strength contrasts that exist at the plateau margins.
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影响因子：
5.2
作者：
Hua Wang;Tim J. Wright;Juliet Biggs
通讯作者：
Hua Wang;Tim J. Wright;Juliet Biggs
影响因子：
5.8
作者：
A. Draut;P. Clift
通讯作者：
A. Draut;P. Clift
DOI：
10.1109/tgrs.2002.803792
发表时间：
2002-11-01
影响因子：
8.2
作者：
Berardino, P;Fornaro, G;Sansosti, E
通讯作者：
Sansosti, E
影响因子：
8.2
作者：
Ferretti, A;Prati, C;Rocca, F
通讯作者：
Rocca, F
DOI：
10.1007/978-3-642-11741-1_11
发表时间：
2010
期刊：
--
影响因子：
--
作者：
Ye Xia
通讯作者：
Ye Xia