在Fennoscandia冰川静态调整的空间地质约束
G A Milne1, J L Davis, J X Mitrovica
1Department of Geological Sciences, University of Durham, Durham DH1 3LE, UK. g.a.milne@durham.ac.uk
概括
全球定位系统 (GPS) 数据显示,冰川的静态平衡调整驱动了Fennoscandian地变形. 这项研究改进了地球模型,并估计了区域海平面上升,排除了显著的构造运动.
科学领域:
- 地质物理学 地质物理学
- 固体地球地力学 地力学
- 冰川学的冰川学
背景情况:
- 芬诺斯坎迪亚正在经历正在进行的地变形.
- 了解这种变形对于地球科学模型和海平面变化评估至关重要.
研究的目的:
- 用全球定位系统 (GPS) 数据分析费诺斯坎迪亚的三维地变形.
- 开发一个由地质数据和GPS观测所限制的地球模型.
- 为了估计区域海平面上升和水平构造运动.
主要方法:
- 来自GPS数据的三维地变形的分析.
- 将GPS观测与数值预测进行比较,以开发一个地球模型.
- 将GPS衍生的辐射运动与Fennoscandian潮计记录集成.
- 基于GPS衍生的地速度场的水平构造运动的评估.
主要成果:
- 冰川同静调整是Fennoscandian地变形的主要驱动因素.
- 这项研究为平均上层地幔粘度 (5 x 10^20到1 x 10^21 Pa s) 和石层弹性厚度 (90170公里) 提供了边界.
- 区域海平面上升估计为每年2.1 ± 0.3毫米.
- 排除了大约每年超过1毫米的水平构造运动.
结论:
- 全球定位系统数据证实冰川静态调整是Fennoscandian地运动的主要原因.
- 衍生的地球模型与独立的地质约束相一致.
- 这些发现有助于更好地了解地幔粘度,石质层结构和该地区的海平面变化.
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