BBLA redesign w/ contros The Benthic Boundary Layer Array: A Modular, Reconfigurable Seafloor Observatory Node N. Farr, C. Pontbriand, J. Ware, J. Kapit and R. Camilli The Benthic Boundary Layer Array: A Modular, Reconfigurable Seafloor Observatory Node N. Farr, C. Pontbriand, J. Ware, J. Kapit and R. Camilli GULF OF MEXICO HYDRATES RESEARCH CONSORTIUM ANNUAL MEETING Oct , 2010 GULF OF MEXICO HYDRATES RESEARCH CONSORTIUM ANNUAL MEETING Oct , 2010

Re-deployment operations Sept 2010 Engineering work completed Integrated Contros methane sensor (power requirement 20W!!) Recalibrated full suite of sensors Reconfigured for –multiple power systems, –asynchronous duty cycle, –independent data logging Deployment completed Deployed September 2010 in SW crater area Anticipated operational endurance 6-9 months Data will be compared with 2009 deployment to: – investigate SW crater hydrocarbon expulsion activity –Monitor for overprinting of hydrocarbons from DWH spill

Benthic turbine a low water velocity electric generator for continuous recharging of the BBLA Operational requirements High efficiency enabling power generation in low velocity (<0.2 m/s) currents Light in-air weight to facilitate deployment, near- neutral in water to minimize flotation requirement Modular design, enabling compact storage on ships pre/post deployment Safely operate in currents up to 0.5 m/s Calculated benthic water column velocity distribution at MC118 (based on nearby MMS data)

Results from trials Tested in well on WHOI dock Begins rotating in 5 cm/s currents Produces ~1 W of power in <0.5 m/s currents ~10 ft dia, 6 ft high and 200 lb in air Components pack flat and turbine is easy to assemble

CORK Optical Telemetry System Wireless data transfer from seafloor instrument to surface vessel Increase power to the CORK for higher bandwidth operation

Sensitive hemispherical receiver 2-inch PMT Wide field of view gathers out- of-plane light. AGC with blanking circuit Dynamic range Ws to 100s-nW Optical Technology High power hemispherical transmitter 24 commercial LEDs 6 W avg. optical power

7 Lowered system mounted on light bar (blue) CORK system on basket (green)

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9 CTD mounted OTS USBL transponder SDSL modem for CTD cable transmission

Transects with lowered unit Range (meters)Data transfer rate (mbps) 1081, 5, ,5 1281,5 1381

Measured power-vs-range