Collaborative Research: Unraveling distributed deformation during early-stage rifting in the Western and Southwestern African Rifts

合作研究：揭示非洲西部和西南部裂谷早期裂谷期间的分布式变形

• 批准号: 2039962
• 负责人: Matthew Pritchard
• 金额: $ 14.58万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2039962&HistoricalAwards=false
• 关键词: Collaborative; Research; Unraveling; distributed; deformation

Rifting, which leads to the breakup of continents and the formation of new ocean basins, is one of the fundamental processes in plate tectonics. East Africa is the prime example of present-day continental rifting. While a number of studies have yielded important insights in the older, more developed rifts in northern East Africa, there are major gaps in our knowledge of how rifting begins and develops due to sparse data in the younger Western and Southwestern rift systems. In particular, there is significant uncertainty about how far ground deformation related to early-stage rifting extends across the region and to what extent deformation may occur without earthquakes. This project will use a combination of ground deformation data from GNSS/GPS data, Synthetic Aperture Radar Interferometry (InSAR), and permanent seismometers to measure and investigate the kinematics of early-stage rifting across the Western and Southwestern rifts. Results will improve our understanding of fundamental tectonic processes and earthquake hazard estimates in the region. The project will provide student research opportunities at both the undergraduate and graduate levels, develop international research collaborations, and contribute to capacity building in science and technology through outreach in secondary schools in the USA and Africa and providing opportunities in training in data processing and analysis through in-country workshops and visits to US research institutions.The overall goal of this project is to test existing models of how rifting is distributed across uplifted and faulted areas of Central Africa surrounding the Western and Southwestern segments of the East African Rift and determine what component of the active rifting is aseismic. To achieve this goal, geodetic measurements, including campaign and continuous GNSS and InSAR, in this under-studied area will be increased. This will provide improved constraints on the tectonic strain field across multiple temporal and spatial scales. Catalogue and regional seismic source data will be combined and then Kostrov summation comparisons of seismic and geodetic observations across the region will be performed in order to evaluate the amount and spatial variation in aseismic deformation and to constrain lithospheric properties. The new geodetic and seismic results will be used to generate an improved model of the kinematics of deformation in the region that is consistent with other geological and geophysical data and can be used to evaluate current models of strain localization in cold, strong lithosphere.This 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.

裂谷导致大陆的破裂和新海盆的形成，是板块构造的基本过程之一。 东非是当今大陆裂变的主要例子。 尽管许多研究在北部非洲的较旧，发达的裂痕中产生了重要的见解，但由于较年轻的西方和西南裂谷系统中的数据稀少，我们的裂谷如何开始和发展存在很大的差距。 特别是，与早期裂隙相关的地面变形在整个地区延伸多远以及在没有地震的情况下可能发生变形的程度，存在明显的不确定性。 该项目将使用来自GNSS/GPS数据，合成孔径雷达干涉仪（INSAR）和永久性地震仪的地面变形数据的组合来测量和研究西部和西南裂谷的早期裂变的运动学。 结果将提高我们对该地区基本构造过程和地震危害估计的理解。 该项目将在本科和研究生层面提供学生的研究机会，发展国际研究合作，并通过在美国和非洲的中学的外展来为科学和技术的能力建设做出贡献东非裂谷的西南段，并确定主动裂谷的哪些组成部分是无向抗病的。 为了实现这一目标，将会提高地测量的测量，包括运动和连续的GNSS和Insar，在这个研究不足的地区。 这将在跨多个时间和空间尺度上对构造应变场的改进约束。 将组合目录和区域地震源数据，然后将进行整个区域的地震和大地测量观测值的Kostrov求和比较，以评估无菌变形的数量和空间变化，并约束岩石圈特性。 新的大地测量和地震结果将用于生成该地区变形运动学的改进模型，该模型与其他地质和地球物理数据一致，可用于评估当前在寒冷的，强质地强的质量定位模型。这一奖项反映了NSF的法定任务，反映了通过评估的构成群体的构成者的构成群体的构成群体的构成师的构成和构成的构成，并构成了基础。