Afloat on a sea of noise

Frederik Simons, at Princeton University, discusses how he developed the Mobile Earthquake Recording in Marine Areas by Independent Divers (MERMAID) instrument. Frederik borrowed the technology called 'Sounding Oceanographic Lagrangian Observers,' (SOLO) floats from the ocean scientists. These can drift at depths of anywhere between the surface and about 1500m. Rapid, precise identification of the signal, exact timing and location accuracy, and a high signal-to-noise ratio are of vital importance for the improvement of seismic tomography. He set about designing algorithms that could identify and pick out arriving seismic sounds, efficiently and reliably, from a sea of noise. MERMAID can quickly filter through the incoming stream of sound with these algorithms onboard. It can identify seismic arrivals that could be useful for seismic tomography and send the results as a series of small messages to one of the many IRIDIUM satellites, which will relay them to land.