标志着人类活动加剧的伟大加速
Xue Zhao1,2, Xiaolin Hou1, Weijian Zhou1,2,3
1Xi'an AMS Center, State Key Laboratory of Loess Science, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, P. R. China.
Environmental science & technology
|January 8, 2025
概括
核试验中的-239,240 (Pu) 提供了大加速的标记. 它在湖泊沉积物中的沉积和保存为这个重要的人类影响时期提供了强大的时间表.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 核科学 核科学 核科学
背景情况:
- 人类活动在20世纪中叶激增,被称为"大加速".
- 核活动是这个时代的一个决定性技术过程.
- 核武试验中的-239,240 (Pu) 沉降物是潜在的年代层学标记物,但其沉积堆积动态仍在争论中.
研究的目的:
- 在湖泊沉积物核心中分析-239,240 (Pu),以确定大加速的精确时间表.
- 研究的积累动态,从大气沉积到不同湖泊环境中的沉积物保存.
主要方法:
- 分析了来自两个玛尔湖的三个沉积物核心,并确定了时间表.
- 在沉积层中测量-239,240 (Pu) 度.
主要成果:
- -239,240的第一次显著增加是在1953年观察到的,这与第一个高产量热核试验相对应.
- -239,240在1963年达到峰值,与全球核试验最高的时期保持一致.
- 在无氧 (西海龙泉湖) 和有氧 (湖湖) 湖环境之间,的清理和保存动态有所不同.
结论:
- 湖泊沉积物中的Pu-239,240沉积物作为大加速的强大和永久的标记.
- 已识别的时间线 (1953年增加,1963年峰值) 准确地反映了主要的核事件和人类影响.
- 湖泊沉积物,特别是无氧环境中的沉积物,为保存这种核时间层图标提供了优秀的档案.
关键词:
湖 Huguangyan 湖 是一个湖泊.西海龙湖是西海龙湖的一个.马尔湖是湖泊中的一个.plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium plutonium氧化还原环境 氧化还原环境再移动化重新动员.相关概念视频
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