在石年代表中解决复杂性: (U-Th) /He铁混凝土年龄显示湿MIS 5c
Matej Lipar1, Milo Barham2, Martin Danišík3
1Anton Melik Geographical Institute, Research Centre of the Slovenian Academy of Sciences and Arts, Ljubljana 1000, Slovenia.
Science advances
|October 2, 2024
概括
使用 (U-Th) /他约会在西澳大利亚的铁混凝土结节约会揭示了102.8万年前的冰河间时期. 这一发现有助于追溯岩地形演变的年代,并了解过去的气候变化.
科学领域:
- 地质形态学 地质形态学
- 古气候学 古气候学
- 地质时间学 (Geochronology)
背景情况:
- 卡斯特地形提供了对景观演变和古气候的洞察力,但很难确定其年代.
- 西澳大利亚普莱斯托时代的岩石表现出强烈的气候变化,形成顶峰的岩和铁结块.
- 确定这些特征的年代对于了解过去的环境动态至关重要.
研究的目的:
- 准确地追溯西澳大利亚普莱斯托时代的岩石中的一个显著的气候变化事件.
- 建立一个时间框架,为该地区的岩地形发展.
- 为了将气候事件与古气候条件相关联.
主要方法:
- 在铁混凝土结节上使用 (U-Th) /He约会.
- 通过光学刺激的发光和U-Th约会在相关的岩石和碳酸盐沉物上得到了支持.
- 应用地质年代学技术到世时代的地质构造.
主要成果:
- 铁混凝土结的年龄为102.8 + 10.6/-11.4万年,相当于海洋同位素阶段5c.
- 在过去的50万年中,该地区最潮湿的冰河间时期直接约定.
- 通过与其他放射测年法进行交叉验证,证实了 (U-Th) /He测年法对铁的可靠性.
结论:
- 铁混凝土结块的 (U-Th) /He年龄为形成顶峰石的溶解事件提供了直接的日期.
- 这种约会方法在全球范围内适用于用于环境变化研究的岩石和相关铁石.
- 这些发现使快速的普莱斯托纪气候振荡和相关的生物圈进化有了更好的时间约束.
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