通爪高原的一个较年轻,较长的位
Peter C Davidson1, Anthony A P Koppers1, Takashi Sano2
1College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, USA.
概括
通爪高原
科学领域:
- 地质科学,古海洋学,火山学
背景情况:
- 通爪高原 (OJP) 的海底火山位与海洋无氧事件1a (OAE 1a) 有关.
- 之前的研究缺乏OJP形成的精确日期,并依靠沉积物代理来确定其OAE 1a连接.
研究的目的:
- 为了完善通爪高原的爆发历史和时间.
- 重新评估OJP和海洋无氧事件1a之间的因果关系.
主要方法:
- 在OJP钻井和疏现场的样本上进行了高精度的40Ar/39Ar地质年代学.
主要成果:
- 新的40Ar/39Ar日期表明OJP形成至少持续了600万年.
- 这些年龄比以前确定的年龄要小1000万年.
- 经过修订的时间表明OJP太年轻而不是OAE 1a的主要原因.
结论:
- 通爪高原的长期形成挑战了其在OAE 1a中的作用,但表明了与后来的OAE 1b的潜在联系.
- 这些发现有助于了解大火山地区的位置动态.
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