地震证据表明,海洋板块的石化层-石化层边界利
Hitoshi Kawakatsu1, Prakash Kumar, Yasuko Takei
1Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan. hitosi@eri.u-tokyo.ac.jp
概括
板块构造学依赖于石化层在天气层上的运动. 了解石化层-石化层边界 (LAB) 揭示了尖的,依赖于年龄的结构,具有丰富的融化层,促进了板块运动.
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:
- 板块构造学描述了石灰岩层在天气层上的运动.
- 石化层-石化层边界 (LAB) 对于理解地球动态至关重要.
- 海洋板块为研究LAB提供了更简单的模型.
研究的目的:
- 为了研究海洋板下LAB的特征.
- 了解天气层的物理状态及其在板块构造学中的作用.
主要方法:
- 来自钻井宽带海洋底地震计的地震数据的分析.
- 剪切波减速的解释.
主要成果:
- 太平洋和菲律宾海板下面的LAB是利的,并且取决于年龄.
- 在LAB观察到剪切波速度的显著减少.
- 证据表明,一个部分化的天气层与水平的融丰富的层.
结论:
- 天气层含有丰富的融化层,在LAB中产生很大的粘度对比.
- 这种粘度对比度促进了水平板块运动,这是板块构造学的一个关键方面.
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