Contrasting active magma- and fault-dominated segments of the East African Rift through the synthesis of InSAR and GPS time series: Implications for rifting dynamics and hazards

东非裂谷系统（EARS）产生大型破坏性地震、山体滑坡和火山灾害，威胁着大量发展中国家的人口，这些人口往往相对而言没有做好充分准备，拥有具有弹性的基础设施。测量地球表面是如何响应这些自然过程而变形的，可以让科学家更好地了解它们和相关的危害。非洲的全球定位系统（GPS）网络很稀疏，网络扩展面临政治和财政两方面的挑战。干涉合成孔径雷达（InSAR）通过对整个ear地面变形的高空间和时间分辨率成像，极大地补充了GPS测量，同时避免了与安装和维护仪器相关的复杂性和成本。除了火山和构造应用之外，结合GPS和InSAR测量地面变形也使科学家能够监测地下水开采等人类活动。了解自然和人为造成的变形对当地社区更好地管理水资源、改善基础设施的规划和发展以及保护自然环境非常重要。该项目的目标是制作精确的时间和空间密集的地壳变形时间序列地图，记录构造、火山和人为相关的变形信号。这将涉及综合和整合以前资助的GeoPRISMS项目收集的GPS数据和InSAR位移时间序列，这些数据横跨EARS的中部部分。这些数据将允许改进表征和比较可能由羽流控制的东部段和可能由断层控制的西部段之间的应变分布，这些部分围绕坦桑尼亚克拉通分支，将这些观察结果置于地质历史和预先存在的结构的背景下。这项工作的结果将提供可靠的地壳变形测量，以支持与裂谷动力学相关的各种研究问题。此外，它将为模拟ear中部、东部和西部段的裂谷形成和演化提供关键约束，并扩展应用于人为变形。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The East Africa Rift System (EARS) produces large damaging earthquakes, landslides, and volcanic hazards that threaten large developing populations that tend to be relatively less well-prepared with resilient infrastructure. Measuring how the surface of the Earth deforms in response to these natural processes allows scientists to better understand them and the associated hazards. The Global Positioning System (GPS) network in Africa is sparse, and network expansion has both political and financial challenges. Interferometric Synthetic Aperture Radar (InSAR) greatly complements GPS measurements with high spatial and temporal resolution imagery of ground deformation over the entire EARS, while avoiding the complications and costs associated with installing and maintaining instrumentation. Beyond volcano and tectonic applications, combining GPS and InSAR measurements of ground deformation also allows scientists to monitor anthropogenic activities such as groundwater extraction. Understanding both natural and anthropogenic-related deformation is important for local communities for better water management, improved planning and development of infrastructure, and protection of natural environments.The objective of this project is to produce precise maps of temporally and spatially dense crustal deformation time series across the central EARS documenting tectonic, volcanic, and anthropogenic related deformation signals. This will involve synthesizing and integrating GPS data collected by previously funded GeoPRISMS projects with InSAR displacement time series across the central section of the EARS. These data will allow for improved characterization and comparisons of distributions of strain between the likely plume-controlled eastern segment and the likely fault-controlled western segment that branches around the Tanzania Craton, placing these observations in the context of the geologic history and pre-existing structures. Results from this work will provide reliable measurements of crustal deformation to support a diverse range of research questions related to rift dynamics. Additionally, it will provide critical constraints for modeling rift initiation and evolution on the central, eastern, and western segments of the EARS, with extended applications to anthropogenic deformationThis award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.