Countrywide Observations of Plate Spreading and Glacial Isostatic Adjustment in Iceland Inferred by Sentinel-1 Radar Interferometry, 2015-2018
Countrywide Observations of Plate Spreading and Glacial Isostatic Adjustment in Iceland Inferred by Sentinel-1 Radar Interferometry, 2015-2018
复制标题
DOI：
10.1029/2019gl082629
复制
发表时间：
2019-07-28
影响因子：
5.2
通讯作者：
Sigmundsson, Freysteinn
中科院分区：
文献类型：
--
作者：
Drouin, Vincent;Sigmundsson, Freysteinn
使用来自六个不同轨道的卫星图像，从哨兵一号雷达干涉测量中提取了冰岛2015-2018年超过81%的东西向和垂直地面速度。只考虑夏季图像，以避免积雪。使用一种简单的方法来估计每个轨道2015-2018年的平均视线速度场：单主干涉测量时间序列与每个像素的线性分量估计相结合。对视线速度场进行组合，并对其信号进行分解，以提取近似的东方(近东)和近似的垂直(近)速度。只有通过一致性和离群值标准的像素才被考虑，导致冰岛81%的覆盖率。缺失的19%的覆盖范围主要是冰川和农田。我们发现，近东速度场与修正的板块扩张模型、近东速度场与冰川均衡调整模型基本一致。模型及其残留物表明，冰岛裂谷带之间的流变学存在差异。
East-west and vertical ground velocities for 2015-2018 are retrieved over 81% of Iceland from Sentinel-1 radar interferometry, using satellite images from six different tracks. Only summertime images are considered, to avoid snow cover. Average line-of-sight velocity fields for 2015-2018 for each track are estimated using a simple approach: single master interferometry time series together with a linear component estimation for each pixel. The line-of-sight velocity fields are combined and their signal is decomposed to extract approximate east (near-East) and approximate vertical (near-Up) velocities. Only pixels passing a coherence and outlier criteria are considered, resulting in 81% coverage of Iceland. The 19% of missing coverage is mostly glaciers and farmland. We find a general agreement between the near-East velocity field and a revised plate spreading model, and the near-Up velocity field and a glacial isostatic adjustment model. Models and their residuals suggest a difference in rheology between the rift zones in Iceland.