Accession Number : ADA305982

Title :   Seafloor Data Loggers. Phase 1.

Descriptive Note : Final rept. 1 Jun-30 Nov 95,

Corporate Author : SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA

Personal Author(s) : Orcutt, John ; Constable, Steve

PDF Url : ADA305982

Report Date : MAR 1996

Pagination or Media Count : 13

Abstract : 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.

Descriptors :   *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.

Subject Categories : Physical and Dynamic Oceanography
      Computer Hardware

Distribution Statement : APPROVED FOR PUBLIC RELEASE