概括
聚合边缘的高基岩 (HAB) 可能由深层基岩融形成. 随着这些融物上升,压力下降会导致石类结晶,解释了它们没有积累的组成.
科学领域:
- 地质化学和石矿学
- 火山学和岩过程
背景情况:
- 收边缘的特点是独特的岩石,包括富含类的高基岩 (HABs).
- 了解HABs的起源对于理解这些构造环境中的岩过程至关重要.
研究的目的:
- 为了研究富含酸盐,高基岩 (HABs) 的石化过程.
- 为了确定压力变化和水含量在HAB形成中的作用.
主要方法:
- 在不同压力下 (3千巴和1千巴) 对玄武岩进行了湿试验.
- 分析了由此产生的液体和共存的矿物质组合.
主要成果:
- 高含量的液体在3千巴的压力下产生,质结晶最小.
- 一个显著的压力下降到1千巴,诱导了这些融物中20%-30%的石质结晶.
- 马菲克矿物在压力降低过程中显示出有限的结晶或再吸收.
结论:
- 水性 (>=4%H2O) HAB液体,在深度可能分成部分,由于压力下降,在上升过程中沉大量的平流.
- 原积不是原丰富的HABs石化的一个先决条件.
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