相关实验视频
Updated: Jul 12, 2026

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Resurrection of Dormant Daphnia magna: Protocol and Applications
Published on: January 19, 2018
古世 - 世热极值和东北大西洋的开放
Michael Storey1, Robert A Duncan, Carl C Swisher
1Quaternary Dating Laboratory, Department of Environment, Society and Spatial Change, Roskilde University Centre, Post Office Box 260, 4000 Roskilde, Denmark.
概括
古世 - 世热极值 (PETM) 是由在格陵兰岛 - 欧洲板块边界附近的火山活动中释放温室气体引发的. 这一事件发生在大规模的洪水玄武岩喷发大约5610万年前开始之后.
科学领域:
- 古气候学 古气候学
- 地质时间学 (Geochronology)
- 板块构造学是一种板块构造学.
背景情况:
- 古世 - 世热极值 (PETM) 是一个重要的全球变暖事件.
- 以前的假设将PETM归因于突然释放的二氧化碳和/或甲.
研究的目的:
- 精确地追溯围绕PETM的关键地质事件.
- 为了将火山活动与PETM开始相关联.
- 调查PETM的触发机制.
主要方法:
- 使用了40Ar/39Ar的年龄测定.
- 在丹麦的Ash-17矿床和斯克兰特纳形成的Tuff中进行了测定.
- 将这些沉积物与PETM和大陆分裂事件相关联.
主要成果:
- 丹麦的Ash-17矿床和Skraenterne形成的Tuff矿床是同一个时期的.
- PETM的出现是在大规模的洪水基岩火山运动 (56.1 +/- 0.4 Ma) 开始之后发生的.
- 这种PETM发生的时间与估计的大陆分裂时间 (55.5 +/- 0.3 Ma) 差不多.
结论:
- 格陵兰东部的大规模火山活动与PETM有关.
- PETM很可能是由岩与格陵兰-欧洲板块边界附近的富含碳沉积物相互作用引发的.
- 这种相互作用释放了温室气体,导致PETM.
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