Spatial localization of moment deficits in southern California
Spatial localization of moment deficits in southern California
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DOI：
10.1029/2004jb003331
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发表时间：
2004-12
影响因子：
--
通讯作者：
B. Meade;B. Hager
中科院分区：
文献类型：
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作者：
B. Meade;B. Hager
[1]地震间弹性应变累积和同震释放之间的平衡定义了断层系统在多大程度上表现出大地震的过剩或不足。我们根据由GPS测量约束的震间变形块体模型估计的断层滑动速率目录，计算了南加州的区域矩累积速率。标量矩累积速率为17.8±1.1×1018Nm/年，比过去200年的平均矩释放速率大约50%。累积和释放的弹性位移场之间的差异与位于三个区域的力矩亏损一致：圣安德烈亚斯和圣哈辛托断裂南部，近海断裂和洛杉矶和文图拉盆地，以及加州东部剪切带。时刻预算可以通过综合震级为Mw≈8的同震事件来平衡。
[1] The balance between interseismic elastic strain accumulation and coseismic release defines the extent to which a fault system exhibits a surplus or deficit of large earthquakes. We calculate the regional moment accumulation rate in southern California based on a fault slip rate catalog estimated from a block model of interseismic deformation constrained by GPS measurements. The scalar moment accumulation rate, 17.8 ± 1.1 × 1018 N m/yr, is approximately 50% larger than the average moment release rate over the last 200 years. Differences between the accumulated and released elastic displacement fields are consistent with moment deficits that are localized in three regions: the southern San Andreas and San Jacinto faults, offshore faults and the Los Angeles and Ventura basins, and the Eastern California Shear Zone. The moment budget could be balanced by coseismic events with a composite magnitude of Mw ≈ 8.