GPS constraints on deformation in northern Central America from 1999 to 2017, Part 2: Block rotations and fault slip rates, fault locking and distributed deformation
GPS constraints on deformation in northern Central America from 1999 to 2017, Part 2: Block rotations and fault slip rates, fault locking and distributed deformation
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1999年至2017年中美洲北部变形的GPS约束，第2部分：地块旋转和断层滑动速率、断层锁定和分布式变形
DOI：
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发表时间：
2019
影响因子：
2.8
通讯作者：
B. Tikoff
中科院分区：
文献类型：
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作者：
A. Ellis;C. Demets;R. Mccaffrey;P. Briole;Beatriz Cosenza Muralles;O. Flores;M. Guzmán;D. Hernández;V. Kostoglodov;P. LaFemina;N. Lord;C. Lasserre;H. Lyon‐Caen;Manuel Rodriguez Maradiaga;E. Molina;J. Rivera;R. Rogers;A. Staller;B. Tikoff
我们描述了一个新的弹性运动学模型，用于描述中美洲北方和墨西哥南部目前的构造，其中的莫塔瓜-波罗奇克断层带、中美洲俯冲带和中美洲火山断层构成了重大的地震灾害。新模型包括八个板块和块体的角速度、一些块体边界断层的震间锁定解和三个具有显著内部变形的块体的应变率张量，优化了对区域断层方位角和地震滑动方向的拟合，以及一个新的200多站GPS速度场，该速度场已针对同震和震后进行了校正，2009年和2012年发生的三次大地震。从我们的新观测和建模中，我们发现了以下证据：洪都拉斯危地马拉城地堑;上述西至西北偏西的Chortis和Ipala区块，以及在两个区块内分布的ENE-WSW延伸;在Motagua断层与Polochic断层上仅占%; Motagua向西14危地马拉城地堑;（5）沿沿着中美洲火山弧断层的滑动速率，该断层从12.5延伸穿过新定义的丰塞卡地块。危地马拉北方和墨西哥南部地区的速度模式可能是由该地区的分布变形或我们的模型和/或假设的缺陷造成的。控制区域变形的主要因素似乎包括Motagua断层的弧形几何形状、中美洲俯冲界面的低锁定、中美洲弧前片前缘与北美板块之间的缓慢至无运动以及流变学上弱的火山弧。
SUMMARY We describe a new elastic-kinematic model for the present tectonics of northern Central America and southern Mexico, where the Motagua-Polochic fault zone, Middle America subductionzoneandfaults intheCentral Americavolcanicarcposesignificant seismichazards. The new model, which consists of the angular velocities for eight plates and blocks, interseismic locking solutions for some of the block-bounding faults and strain-rate tensors for three blocks with significant internal deformation, optimizes the fit to regional fault azimuths and earthquake slip directions and a new 200 + station GPS velocity field that has been corrected for the coseismic and post-seismic effects of three large regional earthquakes in 2009 and 2012. From our new observations and modelling thereof, we find evidence for the following: Honduras Guatemala City graben; of the above W-to-WNW of Chortis and Ipala blocks and distributed ENE-WSW stretching within both blocks; in Motagua fault versus only per cent on the Polochic fault; Motagua westwards 14 Guatemala of the Guatemala City graben, respectively; (5) Slip rates along Central America volcanic arc faults that from 12.5 extension across the newly defined Fonseca block. A pattern of misfits to the velocities of sites in northern Guatemala and southern Mexico may be caused by distributed deformation in this region or shortcomings with our model and/or assumptions. The primary factors that control the regional deformation appear to include the arcuate geometry of the Motagua fault, low locking of the Middle America subduction interface, slow-to-no motion between the leading edge of the Central America forearc sliver and North America plate and a rheologically weak volcanic arc.
影响因子：
3.9
作者：
Li, Shaoyang;Moreno, Marcos;Oncken, Onno
通讯作者：
Oncken, Onno