A Wide-aperture Geodetic Experiment in the Divergent Oceanic Plate Boundary Zone of Iceland

研究人员正在建立一个最近建立的国际合作，包括来自冰岛、瑞士、法国、日本和美国的机构。该项目和合作的目的是利用类似于EarthScope PBO网络的密集大孔径高速率连续GPS （CGPS）网络，研究与冰岛分散的海洋板块边界带相关的复杂四维地壳变形场。目标包括描述冰岛中央高地复杂的时空变形模式，冰岛是全球海洋中脊系统中暴露在海平面以上的最宽部分，位于重叠的西火山区（WVZ）和东火山区（EVZ）之间。研究人员正在开发新的模型来分析随时间变化的变形过程，例如通过塑性屈服恢复深部弹性应变，填充或清空岩浆房，对变化的地表和地下载荷的粘性和弹性响应，以及地球科学界广泛感兴趣的类似过程。它们将分别对“Hreppar地块”的大小以及沿其南部和北部边界的扩散剪切带和裂谷带的宽度提供新的约束，这与山脊传播过程有关，并对冰岛中部地壳垂直运动模式提供新的约束，对过去和现在的冰川退缩、水文过程、地表侵蚀、岩浆运动等过程具有重要意义。该项目将扩大我们对一般岩石圈过程的理解，涉及许多广泛的主题，包括海洋岩石圈流变学、现在和过去的冰川负荷、地表侵蚀、地壳和地幔动力学、火山和地震灾害。冰岛中部的CGPS还促进了冰岛地震网的扩展，补充了正在进行的InSAR和基于运动的GPS调查，并为天气和气候研究提供了新的数据。该项目为RESESS （Solid Earth Science research experience for Students）实习生提供研究经验。

The researchers are builing upon a recently established international collaboration that includes institutions from Iceland, Switzerland, France, Japan, and the United States. The intent of the project and collaboration is to investigate the complex four-dimensional crustal deformation field associated with the divergent oceanic plate boundary zone of Iceland using a dense wide-aperture high-rate continuous GPS (CGPS) network much like the EarthScope PBO network. Goals include characterizing the complex spatial and temporal pattern of deformation in the central highlands of Iceland, the broadest segment of the global mid-ocean ridge system exposed above sea level, located between the overlapping West Volcanic Zone (WVZ) and East Volcanic Zone (EVZ). The researchers are developing new models for analysis time-dependent deformation processes, such as recovery of elastic strain at depth via plastic yielding, filling or emptying of magma chambers, viscous and elastic responses to changing surface and subsurface loads, and similar processes of broad interest to the geosciences community. They will provide new constraints on the size of the "Hreppar block" and the breadth of diffuse shear and rifting zones along its southern and northern boundaries, respectively, which bears on the process of ridge propagation, and new constraints on the pattern of vertical crustal motion in central Iceland, with important implications for past and present glacial retreat, hydrological processes, surface erosion, magma movement, and other processes. The project should broaden our understanding of general lithospheric processes, bearing on many broad themes, including the rheology of oceanic lithosphere, present and past glacial loads, surface erosion, crustal and mantle dynamics, and volcano and earthquake hazards. CGPS in central Iceland is also facilitating expansion of the Icelandic seismic network, complementing ongoing InSAR and campaign-based GPS investigations, and providing new data for studies of weather and climate. The project is providing research experience for RESESS (Research Experience in Solid Earth Science for Students) interns.