太阳原行星盘中固体的绝对时间表和热处理
James N Connelly1, Martin Bizzarro, Alexander N Krot
1Centre for Star and Planet Formation and Natural History Museum of Denmark, University of Copenhagen, DK-1350 Copenhagen, Denmark. connelly@snm.ku.dk
概括
在太阳系早期,富含和的含有物 (CAI) 和状物一起形成. 它们的形成发生在类似的短暂时期,挑战了以前关于时间差距的想法.
科学领域:
- 太空进化的宇宙进化.
- 行星科学 行星科学
- 地质时间学 (Geochronology)
背景情况:
- 富含和的含 (CAI) 和圆柱体的形成是太阳系早期的关键事件.
- 了解这些事件的精确时间对于太阳系进化模型至关重要.
- 之前的研究表明,CAI和chondrule形成之间存在时间差距.
研究的目的:
- 为了确定个别CAI和chondrules的绝对年龄.
- 为了建立CAI和chondrule形成之间的时间关系.
- 为了完善太阳原行星盘演化的模型.
主要方法:
- 使用U校正的- (Pb-Pb) 约会技术.
- 分析了来自原始石的个别CAI和chondrules.
- 应用高精度地质时间分析.
主要成果:
- 在4567.30 ± 0.16百万年前,CAI在狭窄的间隔内形成.
- 宏德鲁形成的时间从4567.32 ± 0.42到4564.71 ± 0.30百万年前.
- 孔德鲁形成与CAI同时开始,并持续了大约300万年.
结论:
- 这项研究驳斥了CAI和chondrules之间的显著年龄差距.
- CAI和chondrule形成是重叠和同时发生的过程.
- 观察到的时间尺度与推断的太阳磁盘寿命保持一致,这表明与磁盘进化有联系.
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