从660公里的边界地形推断地球的不连续化学层
Wenbo Wu1,2,3, Sidao Ni4, Jessica C E Irving2
1State Key Laboratory of Geodesy and Earth's Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China.
概括
研究人员使用地震波在660公里的边界发现了显著的短尺度地形. 这一发现表明化学层次和不完美的地幔循环在地球之间
科学领域:
- 地质学
- 地震学
- 固体地球动力学
背景情况:
- 了解地球的内部动力学依赖于地图界面地形.
- 六百六十公里的边界将上层和下层地幔分开,其大规模地形已得到充分研究.
- 在这个边界进行小规模的地形测量是具有挑战性的.
研究的目的:
- 调查660公里边界的小规模地形.
- 探索观察到的地形对地幔结构和动态的影响.
主要方法:
- 对分散的PP地震波进行分析.
- 绘制短尺度的地形变化.
主要成果:
- 在特定地区的660公里边界发现了显著的短尺度地形.
- 与化学分层相关的高短尺度粗度.
- 在410公里的边界上没有观察到类似的小规模地形.
结论:
- 发现支持在660公里的边界上存在化学分层.
- 观测表明地球上层和下层之间的循环部分受阻或不完美.
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