Seafloor Data Loggers. Phase 1.

• Main Authors: Orcutt, John, Constable, Steve
• Other Authors: SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA
• Format: Text
• Language: English
• Published: 1996
• Subjects: Physical and Dynamic Oceanography; Computer Hardware; *OCEANOGRAPHIC DATA; *DATA ACQUISITION; *OCEAN BOTTOM; *MAGNETIC DISKS; *MAGNETIC DRIVES; LOW POWER; SPATIAL DISTRIBUTION; DEPLOYMENT; COMMERCE; CLOCKS; RATES; CRYSTALS; FRACTURE(MECHANICS); COSTS; CODING; SAMPLING; SEISMIC WAVES; DRIVES; INSTRUMENTATION; RECORDING SYSTEMS; DATA COMPRESSION; HYDROPHONES; REFRACTION; ONBOARD; MASS STORAGE; *SEAFLOOR INSTRUMENTS; L CHEAPO(LOW COST HARDWARE FOR EARTH APPLICATIONS AND PHYSICAL OCEANOGRAPHY); PHYSICAL OCEANOGRAPHY; Antarctic; Australian-Antarctic Discordance; Antarc*
• Online Access: http://www.dtic.mil/docs/citations/ADA305982; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA305982

The current demand for large spatial armys of seafloor instruments and deployment times of up to 12 months can be best fulfilled by inexpensive, low-power data loggers with modern commercial magnetic disk drives for on-board mass storage. We recently designed, constructed, tested, and used 6 seafloor data loggers equipped with hydrophones for seismic refraction experiments on the Clipperton Fracture Zone and Australian-Antarctic Discordance. The instruments are based on Onset's Tattletale microcomputer, weigh only about 70 kg in air, and cost much less than existing instruments of comparable capability. They can be powered for up to one year, using expendables costing as little as $300 for shorter deployments, and record up to 4 Gbyte of data on disk drives using currently available hardware (10 Gbyte are available at this time), which with modest data compression would allow a sampling rate of 256 Hz over a yean Using modern clock crystals, timing can be corrected to 0.1 s/year or better.