海水硫同位素在白纪的波动
Adina Paytan1, Miriam Kastner, Douglas Campbell
1Department of Geological and Environmental Sciences, Stanford University, Stanford CA 94305-2115, USA. apaytan@pangea.stanford.edu
Science (New York, N.Y.)
|June 12, 2004
概括
纪硫循环显示较轻的硫同位素,可能来自火山活动. 硫同位素的变化表明有机碳埋葬和大气氧气水平的变化.
科学领域:
- 地球科学 地球科学 地球科学
- 生物地质化学生物地质化学
- 古气候学 古气候学
背景情况:
- 外源硫循环是地球生物地球化学的组成部分,与碳和氧循环密切相关.
- 了解过去的硫循环,可以了解全球环境动态.
研究的目的:
- 呈现海水硫酸盐在白时期的硫同位素组成的高分辨率记录.
- 调查白纪硫循环变化的驱动因素和影响.
主要方法:
- 在海水硫酸盐中分析硫的同位素成分.
- 高分辨率的地球化学记录重建.
主要成果:
- 在白纪期间,同位素轻硫的普遍丰富,可能与火山和热水活动的增加有关.
- 向较轻硫同位素的两个不同的探险表明,矿埋葬率降低了.
- 硫和无机碳同位素的同时变化表明大气氧气的短期波动.
结论:
- 甲时期的硫循环变化受到火山活动和有机碳埋葬地点的变化的影响.
- 海水硫酸盐同位素的波动提供了地球生物地质化学系统和大气组成的动态变化的证据.
相关概念视频
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