在深处的圣安德烈亚斯断层上,周期性,混乱和翻倍的地震复发间隔
1U.S. Geological Survey, Menlo Park, CA 94025, USA. dshelly@usgs.gov
概括
加利福尼亚州帕克菲尔德附近的小地震显示,在3-6天的间隔内重复的模式. 这些地震复发模式虽然复杂,但可能会为更大的地震事件的时间提供见解.
科学领域:
- 地质物理学 地质物理学
- 地震学 地震学
- 地震科学 地震科学 地震科学
背景情况:
- 了解地震复发对于地震危险评估至关重要.
- 大型地震的长时间复发间隔限制了对它们的变化性的研究.
- 小地震提供了一个更容易访问的窗口到复发模式.
研究的目的:
- 分析低频地震爆发的复发模式.
- 研究地震序列的时间复杂性和可变性.
- 探索小型和大型地震复发之间的潜在并行.
主要方法:
- 一个8.5年的地震数据序列的分析.
- 对超过900次低频地震爆发的复发间隔的量化.
- 识别振荡和复发模式的突然变化.
主要成果:
- 观察到密集集群的低频地震爆发的复发间隔.
- 在复发间隔中确定了振荡,通常在3至6天之间.
- 在地震序列中出现突如其来的模式变化的记录实例.
结论:
- 小地震的复发模式表现出复杂性和可变性.
- 这些发现表明,类似的基础复杂性可能会影响大型地震序列.
- 低频地震分析为理解更广泛的地震行为提供了有价值的代理.
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