地震证据表明,在地幔中存在深水运输
Hitoshi Kawakatsu1, Shingo Watada
1Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan. hitosi@eri.u-tokyo.ac.jp
Science (New York, N.Y.)
|June 9, 2007
概括
地震数据揭示了水如何通过日本的俯冲区深入地球地幔. 水脱离了水合的海洋地,形成了一个地幔通道,将其运送到深层地幔.
科学领域:
- 地质物理学 地质物理学
- 地震学 地震学
- 地球科学 地球科学 地球科学
背景情况:
- 俯冲区对于板块构造和地球深水循环至关重要.
- 了解俯冲区的水运输是理解地幔动态和地震性的关键.
研究的目的:
- 为深层地幔的水运输提供直接的地震证据.
- 为了阐明水运输的机制在一个寒冷的潜水带环境.
主要方法:
- 从日本东北部下面的潜伏区对地震数据的分析.
- 解释地震信号,表明地幔物质含有水分.
主要成果:
- 地震证据证实,在浅深 (<100公里) 的水合海洋地中释放出水.
- 在流板上形成了水合地幔物质的通道,作为深地幔水运输的通道.
结论:
- 水从海洋被有效地运送到深层地幔,通过在寒冷的潜水区的特定路径.
- 这项研究为全球水循环和地幔地化学中的一个关键过程提供了直接证据.
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