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Updated: Jul 12, 2026

08:14
Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
概括
深海的顿岩床揭示了北太平洋的周期性代火山历史. 火山活动周期性地达到顶峰,在米奥森和四季纪出现了更多的事件,这挑战了以前对火山记录的解释.
科学领域:
- 地质地质地质地质地质地
- 古气候学 古气候学
- 火山学 火山学是一门学科.
背景情况:
- 深海顿岩床对于了解中纪火山历史至关重要.
- 之前的研究忽视了土岩床,可能误解了火山活动时间表.
- 识别改变的 (岩) 和不改变的灰层是准确识别火山事件的关键.
研究的目的:
- 为了重建北太平洋的纪火山历史,包括阿列乌提亚山脉和卡姆查特卡半岛.
- 研究过去2000万年来火山活动的周期性.
- 重新评估深海钻探项目192号地点的火山记录及其对板块运动理论的影响.
主要方法:
- 对深海沉积物核心的分析,特别是识别和描述本托尼特和不变的灰层.
- 火山灰层的放射测年法,以建立一个时间框架.
- 火山活动与古海洋学和古气候学数据的相关性.
主要成果:
- 阿列乌提山脉和卡姆查特卡半岛的火山活动呈现周期性模式,在过去的1000万年中每250万年增加一次活动,在1000万年前每500万年增加一次活动,从1000万年前到2000万年前每500万年增加一次活动.
- 中期和晚期的米奥森,以及四级,是整个北太平洋和太平洋盆地的火山活动显著增加的时期.
- 在DSDP地点192没有早期的中新世纪火山活动,这归因于灰层的形成,而不是板块的运动.
结论:
- 周期性火山活动一直是北太平洋中新生代历史的主导特征.
- 在过去的2000万年中,全球主要的火山事件至少发生了两次.
- 增加的火山活动,虽然与四分期冰期相吻合,但可能不是全球冷却的主要驱动因素.
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