Modeling short- and long-term slow slip events in the seismic cycles of large subduction earthquakes
Modeling short- and long-term slow slip events in the seismic cycles of large subduction earthquakes
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模拟大型俯冲地震地震周期中的短期和长期慢滑移事件
DOI：
10.1029/2010jb007566
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发表时间：
2010
影响因子：
--
通讯作者：
K. Obara
中科院分区：
文献类型：
--
作者：
T. Matsuzawa;H. Hirose;B. Shibazaki;K. Obara
[1]慢滑动事件（SSEs）发生在俯冲带中预计会发生大的板间地震的较深区域，如日本的南海地区和北美的卡斯卡迪亚地区。在南海地区，根据持续时间和复发间隔，SSE分为长期和短期SSE。我们模拟和检查的发生长期和短期的SSE和变化的行为在地震周期的大板间地震。在这些数值模拟中，我们采用了速率和状态相关的摩擦法与截止速度，并假设孔隙流体的分布控制的复发间隔的长期和短期的SSE。重现短期SSE的复发间隔减少在长期SSE，在四国西部，在南海地区观察。两类小震的复发间隔在震间周期的后期都变短。1944年东南海地震的观测结果表明，板间大地震在SSE发生区和大地震锁定区之间成核。我们的数值结果表明，在一个地震周期的应力积累过程中影响的复发行为的SSE。
[1] Slow slip events (SSEs) occur in the deeper extents of areas where large interplate earthquakes are expected in subduction zones, such as the Nankai region of Japan and the Cascadia region of North America. In the Nankai region, SSEs are divided into long- and short-term SSEs, depending on their duration and recurrence interval. We modeled and examined the occurrence of long- and short-term SSEs and changes in their behavior during the seismic cycles of large interplate earthquakes. In these numerical simulations we adopted a rate- and state-dependent friction law with cutoff velocities and assumed that the distribution of pore fluid controls the recurrence interval of both long- and short-term SSEs. The recurrence intervals of reproduced short-term SSEs decrease during a long-term SSE, as observed in western Shikoku, in the Nankai region. The recurrence intervals of both types of SSEs become shorter in the later stages of interseismic periods. Large interplate earthquakes nucleate between the region where SSEs occur and the locked region of the large earthquakes, as suggested from observations of the 1944 Tonankai earthquake. Our numerical results suggest that the stress buildup process in a seismic cycle affects the recurrence behavior of SSEs.