全球新的地球变形模式:季节性周期被检测到
G Blewitt1, D Lavallée, P Clarke
1Nevada Bureau of Mines and Geology, and Seismological Laboratory, University of Nevada, Reno, NV 89557, USA. gblewitt@unr.edu
概括
地球 地球 地球 地球 地球 地球
科学领域:
- 地质物理学 地质物理学
- 固体地球地质物理学
- 地质测量是指地质测量.
背景情况:
- 地球的变形受季节性质量再分配的影响.
- 理论模型可以预测全球变形模式.
- 全球定位系统 (GPS) 的数据提供了精确的地理测量.
研究的目的:
- 为了检测和描述地球变形的全球模式.
- 为了验证地球对表面负荷的弹性反应的理论预测.
- 量化季节性半球间质量交换.
主要方法:
- 利用来自全球定位系统 (GPS) 站点全球网络的精确定位数据.
- 分析了2月至3月和8月至9月之间的变形模式的季节性变化.
- 应用数据逆转技术来确定负载时刻和质量交换.
主要成果:
- 检测到一个全球,一度的变形模式与理论预测一致.
- 在冬季观察到北半球的压缩和南半球的膨胀.
- 量化显著的半球间质量交换,在北半球冬季达到顶峰.
结论:
- 检测到的变形模式代表了固体地球对季节性地表质量负荷的弹性反应.
- 土壤水分,雪和大气的季节性负荷驱动着全球显著的地球变形.
- 这些发现证实了地球半球之间大规模的周期性质量再分配.
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