地球中层的粘度上升
Maxwell L Rudolph1, Vedran Lekić2, Carolina Lithgow-Bertelloni3
1Department of Geology, Portland State University, Post Office Box 751, Portland, OR 97207, USA. maxwell.rudolph@pdx.edu.
概括
科学家发现深层地幔粘度在800-1200公里深度之间显著增加. 这一发现有助于解释诸如停滞不前的构造板块和地幔的现象.
科学领域:
- 地质学
- 地球科学
- 地幔动力学
背景情况:
- 深层地幔粘度影响地球的热演变,羽毛动力学和物质混合.
- 了解地幔分层对于理解大规模地质过程至关重要.
研究的目的:
- 在没有先前假设的情况下推断地球深层的粘性层.
- 研究粘度变化与观察到的深层地幔结构之间的关系.
主要方法:
- 重新分析长波非静电地质数据.
- 使用一种新的方法来确定粘度的变化.
主要成果:
- 在800至1200公里的深度检测到地幔粘度大幅增加.
- 这种粘度增加发生在地幔过渡区域以下.
- 增加粘度的深度与板块停滞和羽翼偏移的地震观测相关.
结论:
- 推断的粘度增加为观察到的深层地幔现象提供了统一的解释.
- 这一发现挑战了关于地幔粘度分层的先前假设.
- 突出了深层地幔动态中的粘度结构的重要性.
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