Seismotectonics of the Lesser Antilles Arc

小安的列斯群岛弧的地震构造

• 批准号: 2892607
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2892607
• 关键词: Seismotectonics; Lesser; Antilles; Arc

Background: Subduction zones are the sites of the world's largest earthquakes, sometimes generating devastating tsunamis. The earthquake potential of the Lesser Antilles Arc (LAA) is poorly known, largely because of the challenge of obtaining data along this arc of small islands. Two historic earthquakes are thought to have been classical subduction thrust events, possibly with tsunamigenic potential. However, the extent of megathrust seismic coupling remains debated. The potential risk to large, poorly-protected communities in the Caribbean region is large.Rationale: In a recent large consortium grant, VoiLA, we collected new seismic data, including seabed-installed instruments, in and around the LAA. Data from our experiment has been used to image the subduction zone in unprecedented detail. We have compiled a preliminary catalogue of earthquakes detected during our deployment and developed a new moment tensor method to characterise faulting styles. We have been able to track how regions of more extensively hydrated incoming plate correlate with concentrations of small earthquakes and enhanced volcanic productivity along the arc. The next stage is to undertake an in-depth analysis of the VoiLA data to improve understanding of earthquake potential of the LAA.This project: In this PhD project the VoiLA seismic data will be used together with thermal and mechanical odels of the subduction zone to improve the understanding of the seismic potential and tectonics of the LAA. Machine learning techniques will be used to identify and locate as many events as possible, to characterise the spatial distribution, size-frequency characteristics and where possible styles of events. These results will be combined with existing earthquake catalogues, and then compared with predictions of the thermal structure and subducting plate stresses from models that are tailored based on our detailed imaging of the subduction zone. Given the LAA is an important end-member, where slow-convergence of The student would join the Imperial Plates, Mantle and Core group working on shallow and deep geophysical imaging, surface processes and mantle dynamics.

背景：俯冲带是世界上最大的地震发生地，有时会产生毁灭性的海啸。小安的列斯群岛弧（LAA）的地震潜力知之甚少，主要是因为获取沿着这一小岛屿弧的数据的挑战。两次历史上的地震被认为是典型的俯冲逆冲事件，可能具有引发海啸的潜力。然而，大推力地震耦合的程度仍然存在争议。理由：在最近的一个大型财团赠款VoiLA中，我们收集了新的地震数据，包括LAA及其周围的海底安装仪器。我们的实验数据已被用于以前所未有的细节拍摄俯冲带。我们已经编制了一个初步的地震目录，在我们的部署和开发一个新的矩张量方法来识别断层类型。我们已经能够追踪更广泛的水化传入板块的区域如何与小地震的集中和沿弧沿着火山生产力的增强相关联。下一阶段是对VoiLA数据进行深入分析，以提高对LAA地震潜力的理解。本项目：在本博士项目中，VoiLA地震数据将与俯冲带的热和机械模型一起使用，以提高对LAA地震潜力和构造的理解。将使用机器学习技术来识别和定位尽可能多的事件，以确定事件的空间分布、规模-频率特征和可能的类型。这些结果将与现有的地震目录相结合，然后与根据我们对俯冲带的详细成像量身定制的模型对热结构和俯冲板块应力的预测进行比较。鉴于LAA是一个重要的端元，在那里缓慢收敛的学生将加入帝国板块，地幔和核心小组工作浅，深地球物理成像，表面过程和地幔动力学。