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  Moored Autonomous Hydrophones
image of hydrophone data acquisition
Diagram of earthquake sound travelling to hydrophone. View animation:
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  Mooring deployment
Hydrophone mooring deployment.
Following the successful use of the U.S. Navy's SOund SUrveillance System (SOSUS) for monitoring low-level seismicity on the Juan de Fuca Ridge, NOAA's Pacific Marine Environmental Laboratory has developed a strategy for monitoring remote areas of the world ocean not covered by fixed hydrophone arrays. This strategy requires the deployment of moored, autonomous, hydrophones. In May, 1996 the array was successfully deployed in the eastern equatorial Pacific to begin long-term monitoring of the East Pacific Rise between 20N and 20S. In February 1999, an array of six hydrophones was deployed in the North Atlantic between 15N and 35N and in June 2002 an additional six hydrophones were deployed between 40-52N along the mid-Atlantic Ridge. Hydrophones were deployed in the Gulf of Alaska for marine mammal monitoring in 2000.