基于辐射相关函数的地震地球结构和地幔流动模型之间的比较
概括
数字模拟表明,地幔过渡区中的障碍物会产生温度模式,但地震数据缺乏证据表明这种分层会影响大规模地幔对流.
科学领域:
- 地质物理学 地质物理学
- 地球科学 地球科学 地球科学
- 计算机建模 计算建模
背景情况:
- 地幔对流驱动板块构造和热量分布.
- 中的过渡区可能包含化学或相变障碍物.
- 了解这些障碍对于地幔动态至关重要.
研究的目的:
- 调查过渡区屏障对地幔对流的影响.
- 将数值模拟结果与地震断层扫描数据进行比较.
- 评估分层对大规模地幔流动的影响.
主要方法:
- 三维数值模拟地幔对流的模型.
- 通过化学或内热相变的模拟流动阻抗.
- 对温度场的分析和与地震剪切速度模型的比较.
主要成果:
- 模拟显示,在施加的障碍处,垂直温度相关长度的明显最小值.
- 这一特征即使在过的数据中仍然存在,表明了稳定性.
- 地震断层扫描数据显示,没有明确的证据表明这种特征.
结论:
- 中层地幔过渡区的分层对大规模地幔循环的影响有限.
- 模型和地震数据之间的差异表明,障碍物不会显著破坏全球地幔流动.
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