海洋天气层的粘度由地震的远程触发推断出来
Pollitz1, Burgmann, Romanowicz
1F. F. Pollitz and R. Burgmann, Department of Geology, University of California, Davis, Davis, CA 95616, USA. B. Romanowicz, University of California Seismological Laboratory, 475 McCone Hall, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|June 5, 1998
概括
1952年至1965年间,太平洋板块边界沿线发生的大规模地震影响了全球的地震活动. 后地震压力变化引发了板内地震,并改变了全球的地震性模式.
科学领域:
- 地质物理学 地质物理学
- 地震学 地震学
- 板块构造学是一种板块构造学.
背景情况:
- 从1952年到1965年,一系列主要的板块间地震发生在阿列乌特弧和库里尔-卡姆查特卡沟沿线.
- 这些事件释放了北太平洋板块边界的很大一部分积累的压力.
研究的目的:
- 为了研究地震后的应力演变,在此次大地震发生后.
- 确定这些应力变化对后续地震活动的影响.
主要方法:
- 使用粘弹性合模型来模拟应力变化.
- 在模型中纳入了5 x 10^17帕斯卡秒的星球粘度.
- 分析了基于速度异常的空间地质测量测量.
主要成果:
- 计算的后地震应力演变与观察到的地震模式是一致的.
- 该模型解释了海洋内部板块地震的触发.
- 它还解释了远程板块边界的时间地震性模式.
- 在7000×7000公里面积的30年后,在30年后的序列中观察到异常速度.
结论:
- 1952年至1965年的地震序列显著影响了太平洋板块的应力分布.
- 后地震应激放松在引发随后的地震和影响全球地震性方面发挥了至关重要的作用.
- 这些发现突出了构造板边界的相互联系.
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