在白纪中期的高地磁强度来自Thellier对单个流石类晶体的分析
J A Tarduno1, R D Cottrell, A V Smirnov
1Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY, 14627, USA. john@earth.rochester.edu
概括
地磁二极子时刻在白纪正常极性超时期间是三倍强的. 这一发现支持低地磁反转频率与高磁场强度之间的联系.
科学领域:
- 地质物理学 地质物理学
- 古磁论是古磁论的一种学说.
- 地动纳摩理论 地动纳摩理论
背景情况:
- 数字模拟表明,地力发电机效率与二极极强度和低反转频率相关.
- 现有的古老强度数据表明,逆转频率和古老强度之间存在脱.
- 纪正常极性超时 (CNPS) 代表了一个长期稳定的地磁极性.
研究的目的:
- 为了研究CNPS期间的古磁二极极时刻.
- 为了测试低地磁反转频率与高古磁二极极矩之间的相关性假设.
- 提供来自CNPS的新古强度数据,以解决与现有数据的差异.
主要方法:
- 来自拉吉马哈尔陷基岩 (113-116亿年前) 的石质晶体的分析.
- 应用56个Thellier-Thellier实验来确定古时强度.
- 计算时间平均的古磁二极极时刻.
主要成果:
- 在CNPS期间的古磁二极极矩被确定为12.5 +/- 1.4 x 10^22 A/m.
- 这一值大约是纪和白纪早期-罗纪晚期平均二极极时刻的三倍.
- 在中世和中世,频繁地磁逆转的时期以较低的二极极时刻为特征.
结论:
- 这项研究提供了强有力的证据,支持低地磁反转频率与高地磁场强度之间的相关性.
- 这些发现挑战了先前对解逆转频率和古古强度的解释.
- 在长时间的稳定极性期间,地力发电机可能会更有效地运行,产生更强的二极子场.
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