来自月球石撞击融化年龄的月球灾难假设的支持
B A Cohen1, T D Swindle, D A Kring
1The University of Arizona, Tucson, AZ 85721, USA. bcohen@utk.edu
概括
月球石为地球月球系统提供了新的见解. 分析显示,大约39亿年前有一个短暂而强烈的轰炸时期,支持月球灾难假设.
科学领域:
- 地质地质地质地质地质地
- 行星科学 行星科学
- 宇宙影响研究 宇宙影响研究
背景情况:
- 与阿波罗和Luna收藏相比,月球石提供了更随机的月球物质样本.
- 重新检查月球灾难假设对于理解太阳系早期历史至关重要.
研究的目的:
- 为了分析月球石撞击融化年龄,重新评估月球灾难假设.
- 为了确定地球月球系统中古代轰炸事件的时间和强度.
主要方法:
- 在月球石 (MAC 88105,QUE 93069,DaG 262,DaG 400) 撞击融样本上使用了40Ar-39Ar测年技术.
- 分析了7到9个不同的撞击事件,这些撞击事件代表着石突破.
主要成果:
- 确定的撞击融化年龄在276亿至392亿年前之间.
- 观察到缺乏撞击融化年龄超过392亿年.
结论:
- 这些发现支持了大约39亿年前短暂而强烈的冲击轰炸时期的模型.
- 这一时期代表了撞击活动的异常高峰,与一般下降的撞击频率曲线不同.
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