Tera3D: A Tera-Scale Full-3D Waveform Tomography (F3DT) in Southern California

We are automating our full-3D waveform tomography (F3DT) and seismic source inversion algorithm based on the scattering-integral (SI) method and applying the automated algorithm to iteratively improve the 3D SCEC Community Velocity Model Version 4.0 (CVM4) in Southern California. In F3DT, the starting model as well as the derived model perturbation is 3D in space and the sensitivity kernels are calculated using the full physics of 3D wave propagation. The SI implementation of F3DT is based on explicitly constructing and storing the sensitivity kernels for individual misfit measurements. Compared with other F3DT implementations, the primary advantages of the SI method are its high computational efficiency and the ease to incorporate 3D Earth structural models into real-time seismic source parameter inversions. In a previous study, we have successfully applied the SI method to improve the 3D seismic velocity structure model (SCEC CVM3) and seismic source models in the Los Angeles region. In this presentation we will report our recent progresses on automating the complete F3DT workflow and extending our analysis to a much larger region in Southern California.