Coupled seismic slip on adjacent oceanic transform faults
Coupled seismic slip on adjacent oceanic transform faults
复制标题
邻近海洋转换断层上的耦合地震滑移
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
Yang Shen
中科院分区：
文献类型：
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作者：
D. Forsyth;Yingjie Yang;Maria‐Daphne Mangriotis;Yang Shen
在四个半小时的时间里，海底地震仪阵列探测到复活节微板块西部边界的地震群中发生了60多起事件。震群中较大的事件是位于两个转换断层上的走滑地震，两个转换断层相距约25公里。断层上的滑动是紧密耦合的，活动在两次转换之间随机地来回交替。耦合地震活动通常归因于由另一个地震产生的传播剪切波中的静态应力变化或动态应力触发，但这些地震太小，任何一种机制都不可信。我们认为，震群可能是一个更大的，主要是地震，滑动事件或慢地震涉及两个转换，可能是由东太平洋扩张中心的堤坝注入触发的地震表现。
In a four and a half hour period, more than 60 events in an earthquake swarm on the western boundary of the Easter microplate were detected by an array of ocean bottom seismometers. The larger events of the swarm were strike‐slip earthquakes located on two transform faults separated by about 25 km. Slip on the faults was closely coupled, with activity alternating back and forth randomly between the two transforms. Coupled seismic activity is usually attributed to triggering by static stress changes or dynamic stresses in propagating shear waves generated by another earthquake, but these earthquakes are too small for either mechanism to be plausible. We suggest that the swarm may have been the seismic manifestation of a larger, primarily aseismic, slip event or slow earthquake involving both transforms, perhaps triggered by dike injection on the Easter‐Pacific spreading center.