芬诺斯坎迪亚地区冰川均衡调整的空间大地测量约束

Space-geodetic constraints on glacial isostatic adjustment in Fennoscandia.

作者信息

Milne G A, Davis J L, Mitrovica J X, Scherneck H G, Johansson J M, Vermeer M, Koivula H

机构信息

Department of Geological Sciences, University of Durham, Durham DH1 3LE, UK.

出版信息

Science. 2001 Mar 23;291(5512):2381-5. doi: 10.1126/science.1057022.

DOI:10.1126/science.1057022

PMID:11264528

Abstract

Analysis of Global Positioning System (GPS) data demonstrates that ongoing three-dimensional crustal deformation in Fennoscandia is dominated by glacial isostatic adjustment. Our comparison of these GPS observations with numerical predictions yields an Earth model that satisfies independent geologic constraints and bounds both the average viscosity in the upper mantle (5 x 10(20) to 1 x 10(21) pascal seconds) and the elastic thickness of the lithosphere (90 to 170 kilometers). We combined GPS-derived radial motions with Fennoscandian tide gauge records to estimate a regional sea surface rise of 2.1 +/- 0.3 mm/year. Furthermore, ongoing horizontal tectonic motions greater than approximately 1 mm/year are ruled out on the basis of the GPS-derived three-dimensional crustal velocity field.

摘要

对全球定位系统（GPS）数据的分析表明，斯堪的纳维亚半岛正在进行的三维地壳变形主要由冰川均衡调整主导。我们将这些GPS观测结果与数值预测进行比较，得出了一个满足独立地质约束的地球模型，该模型界定了上地幔的平均粘度（5×10²⁰至1×10²¹帕斯卡秒）和岩石圈的弹性厚度（90至170公里）。我们将GPS得出的径向运动与斯堪的纳维亚半岛验潮仪记录相结合，估计区域海平面上升速度为2.1±0.3毫米/年。此外，根据GPS得出的三维地壳速度场，排除了正在进行的大于约1毫米/年的水平构造运动。