概括
在高压和高温下蛇形岩石剪切强度的显著下降与其转化为新矿物质有关. 这种地质反应也导致岩石密度显著增加.
科学领域:
- 地质地质地质地质地质地
- 矿物物理 矿物物理
- 高压地质化学 高压地质化学
背景情况:
- 蛇形岩石在俯冲区和构造学环境中很常见.
- 了解蛇形在地幔条件下的行为对于地力学至关重要.
研究的目的:
- 为了研究在高压和高温下蛇形岩石的剪切强度明显下降的原因.
- 在特定的实验条件下识别蛇形中发生的矿物质变化.
主要方法:
- 采用了实验性岩石学和矿物物理技术.
- 切削强度测量是在30-40千巴的压力和300-520摄氏度的温度下对蛇形承载岩石进行的.
主要成果:
- 在指定的压力和温度范围内,在带蛇形岩石中观察到切削强度的显著下降.
- 观察到的剪切强度的减少归因于蛇形的转化为压力依赖的,10-angstrom,2:1层酸盐,布鲁酸盐和危险酸盐.
- 这种矿物转化导致密度大约增加8.5%.
结论:
- 在高压和高温下,蛇形矿物转化为新矿物相,大大降低了岩石的剪切强度.
- 这一发现对了解地球地幔中的岩石的机械行为和密度变化,特别是潜水带的岩石有意义.
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