POSTSEISMIC GPS SURVEY, MODELING, AND EDUCATION FOLLOWING THE M7.0 JANUARY 12, 2010 EARTHQUAKE IN HAITI

2010 年 1 月 12 日海地 M7.0 地震后的震后 GPS 调查、建模和教育

• 批准号: 1045809
• 负责人: Eric Calais
• 金额: $ 41.07万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-02-15 至 2016-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1045809&HistoricalAwards=false
• 关键词: POSTSEISMIC; GPS; SURVEY; MODELING; EDUCATION

On January 12, 2010 a Mw7 earthquake struck the Port-au-Prince region of Haiti, killing an estimated 230,000 people, leaving more than 1.5 million homeless, costing 120% of the country?s GDP, and destroying most governmental, technical, and educational infrastructure throughout this region of 3 million people. Despite warnings from the geoscience community that Haiti was at high risk for an earthquake, the country found itself unprepared. With historical seismicity indicating that this earthquake may be the beginning of a new cycle of large events, it is imperative to understand where seismic hazards are greatest in the years to come, and to prepare the people of Haiti for this eventuality. To this end we will measure postseismic deformation to constrain numerical models of stress transfer and develop a Haiti-specific earthquake education curriculum for use in Haitian high schools. Specifically, this project will (1) measure 3-dimensional postseismic deformation using a combination of existing continuous GPS stations and survey sites that we installed and observed immediately following the January earthquake; (2) use these constraints to validate finite element models of postseismic deformation and infer the relative contributions and depth distributions of the three main postseismic mechanisms: afterslip, poroelastic rebound, and viscoelastic relaxation; and (3) use the resulting finite element models to calculate the evolution of Coulomb stress on regional faults in the years to come to determine which segments are currently being loaded at the fastest rates. The January earthquake is the first large event to occur in the northern Caribbean plate within the geodetic age, and thus provides a key opportunity to use postseismic observations to explore the rheological properties of the lower crust and upper mantle in this region. This work is critical to understanding how transpression at this plate boundary is accommodated at depth, and more imperatively, how postseismic processes are currently working to change the stress field on other active faults in the region. Thus, this work will help to improve improving our understanding of the hazards associated with earthquakes in Haiti following the January 12 event and help define the likelihood that other large earthquakes may be impending along that fault system. The project initiates a capacity building effort in geosciences that is so much needed in Haiti, including the training of Haitian collaborators in the use of modern space geodetic techniques and the education of Haiti?s young. While conducting our GPS work, we will visit Haitian high schools in the towns we pass through to discuss the tectonics and earthquake hazards of Haiti. In addition, we will work with US and Haitian high school teachers and students, in collaboration with Teachers Without Borders to develop an earthquake education curriculum for use in Haitian high schools. The curriculum will focus on regional tectonics, earthquake hazards, and preparedness and planning efforts specific to Haiti in order to create a lasting legacy of earthquake education.

2010年1月12日，一场Mw 7级地震袭击了海地的太子港地区，造成约23万人死亡，超过150万人无家可归，损失了该国的120%。破坏了这个拥有300万人口的地区的大部分政府、技术和教育基础设施。尽管地球科学界警告说，海地有发生地震的高风险，但该国发现自己毫无准备。历史上的地震活动表明，这次地震可能是一个新的大事件周期的开始，因此必须了解未来几年地震危险最大的地方，并使海地人民为这种可能性做好准备。为此，我们将测量震后变形，以限制应力传递的数值模型，并开发一个海地特定的地震教育课程，供海地高中使用。具体而言，本项目将（1）使用我们在1月地震后立即安装和观察的现有连续GPS站和调查点的组合来测量三维震后变形;（2）使用这些约束来验证震后变形的有限元模型，并推断三种主要震后机制的相对贡献和深度分布：后滑、孔隙弹性回弹和粘弹性松弛;以及（3）使用由此产生的有限元模型来计算未来几年区域断层上库仑应力的演变，以确定哪些段目前正以最快的速率加载。1月的地震是第一个大事件发生在北方加勒比板块的大地测量年龄，从而提供了一个关键的机会，利用震后观测，以探讨该地区的下地壳和上地幔的流变特性。这项工作是至关重要的，了解如何在这个板块边界的平移压力是适应在深度，更迫切的是，如何震后过程目前正在努力改变该地区的其他活动断层的应力场。因此，这项工作将有助于提高我们对1月12日事件后海地地震相关危害的了解，并有助于确定该断层系统沿着可能发生其他大地震的可能性。该项目启动了海地急需的地球科学能力建设工作，包括培训海地合作者使用现代空间大地测量技术和海地教育？她很年轻。在进行全球定位系统工作的同时，我们将访问我们所经过的城镇的海地高中，讨论海地的构造和地震危险。此外，我们将与美国和海地的高中教师和学生合作，与无国界教师组织合作，开发一个地震教育课程，供海地高中使用。该课程将侧重于区域构造，地震灾害，并准备和规划工作具体到海地，以创造地震教育的持久遗产。