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

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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.