Concept for a High MEO InSAR Seismic Monitoring System

Demonstration of a spaceborne system to image seismic surface waves dynamically (i.e. coseismically) would be the early steps of a future operational capability for monitoring earthquakes and discriminating clandestine underground nuclear tests. Complementing the global network of seismic instruments, such system would enable unprecedented global mapping of the velocity structure of the Earth´s crust, thereby improving hypocentral location, understanding of rupture dynamics and wave propagation effects, and source characterization. Seismic wave measurement requirements include lower bounds on detectability of events and wave amplitude accuracy for different levels of analysis, such as source characterization and crustal tomography, with 10-100 mum wave amplitude resolution for waves nominally traveling 5 km/s, an upper frequency bound based on earthquake surface displacement spectra, and minimum horizontal resolution (1-5 km) and areal coverage. Advanced radar technologies are keys to demonstrating a pre-operational system leading to a high MEO (10,400 km orbit altitude) constellation for continuous surveillance.