9617623 Webb This grant provides funds to complete development and improve performance of a broad band seafloor hydrophone system for measurements in a band from 1 mHz to 64 Hz. The sensor is designed for observations of Rayleigh waves and short and long period body waves. Presently, the noise level of the sensor does not reach ambient noise levels at frequencies between 0.03 and 0.1 Hz. Proposed work should provide improvements in noise level of up to 40 dB with new components that have become available. This improvement in noise level will allow the detection of long period body waves from smaller earthquakes, and improve the signal to noise for seafloor observations of Rayleigh waves. The enhanced capability will make the new sensor an important tool for future deployments of portable seafloor arrays or of a permanent ocean seismic observatory.
