Alaska is the most tectonically active area in North America with abundant seismic and volcanic activities, and its unique lithosphere structures record a series of tectonic events of collision and deformation. Studying the subsurface structures is crucial for understanding these tectonic processes. Seismic imaging, which builds the Earth’s velocity model by analyzing the travel times of seismic waves, is one of the most important method to map the subsurface structures. The recent increasingly available seismic data in Alaska due to the deployment of USArray provides us with an unprecedented opportunity to conduct seismic imaging in that area.

In this presentation, I will start with a brief overview of the historic and current tectonics in Alaska. Then I will use some examples to illustrate how can we study the subsurface structures by mapping the velocities. Finally, I will talk about our seismic imaging project in Alaska using ambient noise data and the full-waveform inversion technique, including a short introduction of our method and a demonstration of our preliminary result.