Tsunami Hazard Posed to New Zealand by the Kermadec and Southern New Hebrides Subduction Margins: An Assessment Based on Plate Boundary Kinematics, Interseismic Coupling, and Historical Seismicity
Tsunami Hazard Posed to New Zealand by the Kermadec and Southern New Hebrides Subduction Margins: An Assessment Based on Plate Boundary Kinematics, Interseismic Coupling, and Historical Seismicity
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克马德克和新赫布里底群岛南部俯冲边缘对新西兰造成的海啸危害：基于板块边界运动学、震间耦合和历史地震活动的评估
DOI：
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发表时间：
2011
影响因子：
2
通讯作者：
M. Reyners
中科院分区：
文献类型：
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作者：
W. Power;L. Wallace;Xiaoming Wang;M. Reyners
我们评估了克马德克和新赫布里底群岛南部俯冲边缘对新西兰造成的海啸危害。在过去 150 年有据可查的历史中，这两个俯冲带都没有产生足以对新西兰造成重大损害的海啸。然而，由于与地球许多俯冲带发生的重大海啸地震的复发间隔相比，这一时间范围很短，因此不应认为迄今为止观察到的情况代表了长期的情况。对于这两个俯冲带，我们通过地震滑移矢量数据和 GPS 速度的块建模提供了板块运动学和断层锁定结果。结果用于估计通常发生大海啸地震的板块界面上当前的应变累积率。我们还审查了这些边缘发生的较大历史地震的数据，以及自 1976 年以来的全球 CMT 事件目录。利用这些信息，我们开发了一组大地震情景，这些情景已用作 COMCOT 海啸代码的初始条件，以估计随后的海啸在西南太平洋的传播，并据此评估了对新西兰的潜在影响。我们的研究结果表明，如果克马德克海沟南部或中部地区发生大地震（Mw ≳8.5），新西兰北部地区和科罗曼德地区将面临重大威胁，而新赫布里底海沟南部发生类似的大地震有可能对新西兰远北部地区靠近潜艇三王岭南端的地区产生强烈影响。我们提出了每个海沟发生的大地震震级-频率参数的逻辑树，旨在为未来的概率研究奠定基础。
We assess the tsunami hazard posed to New Zealand by the Kermadec and southern New Hebrides subduction margins. Neither of these subduction zones has produced tsunami large enough to cause significant damage in New Zealand over the past 150 years of well-recorded history. However, as this time frame is short compared to the recurrence interval for major tsunamigenic earthquakes on many of the Earth’s subduction zones, it should not be assumed that what has been observed so far is representative of the long term. For each of these two subduction zones we present plate kinematic and fault-locking results from block modelling of earthquake slip vector data and GPS velocities. The results are used to estimate the current rates of strain accumulation on the plate interfaces where large tsunamigenic earthquakes typically occur. We also review data on the larger historical earthquakes that have occurred on these margins, as well as the Global CMT catalogue of events since 1976. Using this information we have developed a set of scenarios for large earthquakes which have been used as initial conditions for the COMCOT tsunami code to estimate the subsequent tsunami propagation in the southwest Pacific, and from these the potential impact on New Zealand has been evaluated. Our results demonstrate that there is a significant threat posed to the Northland and Coromandel regions of New Zealand should a large earthquake (Mw ≳8.5) occur on the southern or middle regions of the Kermadec Trench, and that a similarly large earthquake on the southern New Hebrides Trench has the potential to strongly impact on the far northern parts of New Zealand close to the southern end of the submarine Three Kings Ridge. We propose logic trees for the magnitude–frequency parameters of large earthquakes originating on each trench, which are intended to form the basis for future probabilistic studies.