在石化层-石化层边界观察到丰富的融化道
1Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, USA. snaif@ucsd.edu
Nature
|March 23, 2013
概括
石化层-石化层边界 (LAB) 可能是一个部分化的层,解释了板块构造学. 在海洋板下面的这种低粘度区域起到滑剂的作用,影响了沟附近的沉降动态.
科学领域:
- 地质物理学 地质物理学
- 构造物理学 构造物理学
- 地幔动态地幔动态
背景情况:
- 石化层-石化层边界 (LAB) 对板块构造学至关重要,但它的起源仍有争议.
- 地震研究显示,LAB的速度不连续,部分化或脱水被认为是原因.
研究的目的:
- 为了研究可可板下面的LAB的电导率.
- 为了确定LAB的物理状态和起源.
主要方法:
- 在尼加拉瓜近海采集海底磁数据.
- 在LAB中成像电导率.
主要成果:
- 在LAB中发现了一层高导电层,深度为45-70公里.
- 导电性异构性表明剪切,类似管状的融结构与板块运动平行.
结论:
- 年轻板块下面的LAB被解释为一个部分化的层.
- 这种低粘度的通道将石质层脱,并可能滑板块运动,影响潜水.
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