在粘性弹性地球上,俯冲地震的变形周期
Kelin Wang1, Yan Hu, Jiangheng He
1Pacific Geoscience Centre, Natural Resources Canada, Geological Survey of Canada, Sidney, British Columbia V8L 4B2, Canada. kwang@nrcan.gc.ca
Nature
|April 21, 2012
概括
太空地质测量揭示了地幔粘度控制地震变形周期在俯冲区. 对比研究修改了主要地震事件之间地运动的传统弹性模型.
科学领域:
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
- 地震学 地震学
背景情况:
- 俯冲区产生地球上最强大的地震.
- 在过去的20年里,太空地质学改变了对地震间地变形的研究.
- 现代地质测量数据跨越有限的时间,需要在不同的俯冲区进行比较.
研究的目的:
- 整合来自各种潜水区的地质数据.
- 为了了解短期和长期地幔行为在控制变形中的相互作用.
- 挑战和修订地震变形的传统弹性模型.
主要方法:
- 使用太空测地技术来测量地变形.
- 在地震周期的不同点对俯冲区进行比较分析.
- 合成地质"快照"来构建一个全面的变形模型.
主要成果:
- 间地震变形受到短期 (几年) 和长期 (几十年/几个世纪) 地幔粘度的影响.
- 从比较的地质测量研究中,一个统一的俯冲区变形模型出现了.
- 弹性模型,假定co-seismic和inter-seismic变形作为镜像,正在重新评估.
结论:
- 地幔粘度在调节潜伏区的变形周期中起着至关重要的作用.
- 地测数据的整合提供了对构造过程的更细致的理解.
- 未来的研究应该继续改进结合粘弹性地幔行为模型.
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