概括
下层地幔是下层的地幔.
科学领域:
- 地质物理学 地质物理学
- 矿物物理 矿物物理
背景情况:
- 下层地幔是地球地力学中的一个关键区域,由 (Mg,Fe) SiO3-矿主导.
- 最近的研究表明,这种矿物阶段具有很高的化温度.
研究的目的:
- 调查高矿化温度对下层地幔动态的影响.
- 在这些条件下模拟地幔对流.
主要方法:
- 使用了数值对流模型.
- 模拟探索了各种雷利数和内部加热速率.
主要成果:
- 在模拟的下层地幔中,始终发现低同源温度 (0.3-0.5).
- 高温柔性爬行是可行的,即使在这些较低的温度.
- 具有较低内部加热的模型在中下层地幔中产生粘度最大值,与地球物理观测相一致.
结论:
- 高矿化温度导致下层地幔具有动态"寒冷"的状态.
- 这种"冷"状态允许高温的爬行,并解释了观察到的粘度变化.
- 这些发现使矿物物理与大规模地幔对流和地质数据相协调.
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