这是北美第一个冰川最大
Greg Balco1, Charles W Rovey, John O H Stone
1Quaternary Research Center and Department of Earth and Space Sciences, University of Washington, Seattle, WA 98915, USA. balcs@u.washington.edu
Science (New York, N.Y.)
|January 18, 2005
概括
科学家现在可以使用宇宙射线产生的核化物来测定古代冰川沉积物的年代. 这种使用-10和-26的新方法,可以从陆地证据中重建更古老的冰盖.
科学领域:
- 地质地质地质地质地质地
- 四分学科学 四分学科学
- 地质时间学 (Geochronology)
背景情况:
- 海洋记录显示至少有50个世-普世冰盖的进展.
- 从陆地证据中重建较旧的冰川沉积物是具有挑战性的,因为约会技术有限.
研究的目的:
- 建立一种可靠的方法,使用陆地证据来测定古老的冰川沉积物的年代.
- 为了能够准确地重建过去的冰盖动态.
主要方法:
- 使用宇宙射线产生的核化物:-10 (10Be) 和-26 (26Al).
- 将这些核素应用到日期上,可以发现覆盖着古太阳的土壤.
主要成果:
- 证明了10Be和26Al在约会仪器中的有效性.
- 成功地定年了以前无法定日的冰川沉积物.
结论:
- 宇宙射线核化物约会为重建世-普世冰盖历史提供了一个新的工具.
- 这种方法克服了以前用于测定古老冰川沉积物的年代的技术的局限性.
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