火山活动和冲击加热在大规模灭绝中的作用 气候变化
1Department of Earth Science, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan. kunio.kaiho.a6@tohoku.ac.jp.
Scientific reports
|April 30, 2024
概括
加热温度决定了大规模灭绝期间的气候变化. 低温加热释放二氧化硫 (SO2),导致冷却,而中间加热释放二氧化碳 (CO2),导致变暖,影响地球的气候历史.
科学领域:
- 地质学和古气候学.
- 大规模灭绝事件的地球化学.
背景情况:
- 泛热纪时代的大规模灭绝与显著的气候变化有关,无论是全球冷却还是全球变暖.
- 在灭绝事件期间驱动这些不同的气候变化的潜在机制尚未完全理解.
- 沉积岩的温度是理解这些气候变化的关键因素.
研究的目的:
- 为了研究控制气候变化的机制 (变暖与降温) 在Phanerozoic大灭绝期间.
- 阐明宿主岩石加热温度和时间在挥发性气体排放和随后气候影响中的作用.
- 为了比较火山活动和小行星撞击对气候的影响.
主要方法:
- 分析来自不同温度范围的宿主岩石加热导致的挥发性气体排放 (二氧化硫,二氧化碳,烟尘).
- 研究接触加热和冲击加热对沉积岩的影响.
- 将气体排放与已知的大规模灭绝事件和气候变化相关联.
主要成果:
- 硫化物的低温加热会释放二氧化硫 (SO2),导致全球冷却.
- 碳化合物和碳酸盐的中温加热会释放二氧化碳 (CO2),导致全球变暖.
- 高温加热会释放额外的SO2,冲击加热会产生烟尘,这两种都会导致全球冷却.
结论:
- 主体岩石加热的温度和持续时间是主导挥发性排放的关键决定因素,并在大规模灭绝期间导致气候变化.
- 火山活动和小行星撞击都可能通过岩石加热和气体/粒子释放引发类似的气候变化.
- 了解特定的加热模式是解读重大灭绝事件期间过去气候动态的关键.
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