Contros HydroC Methane Sensor at MC118 Presented by Ken Sleeper Seabed Technology Research Center Mississippi Mineral Resources Institute University of Mississippi October 26,

Why Contros Need for a direct measure of methane on the seafloor Need for a direct measure of methane on the seafloor – PFA, BBLA, CSA and future arrays – Raman Spectrometer, METS sensor, Mid-IR and Mass Spectrometer – Evaluate new near-IR detector Chris Martens’ METS shoot out – Survey Mode Chris Martens’ METS shoot out – Survey Mode Rich Camilli redesign of the power draw – Observatory Mode Rich Camilli redesign of the power draw – Observatory Mode 2

Contros near IR CH4 sensor Key Features Membrane Diffusion Partial Pressures (Henry’s Law) Partial Pressures (Henry’s Law) IR absorption bands of Methane IR absorption bands of Methane Concentration Concentration Pressure Pressure Temperature Temperature Relative Humidity Relative Humidity 3

June 2010 MC118 Cruise 15 CTD CASTS with CDOM and Transmissometer 15 CTD CASTS with CDOM and Transmissometer 5 Casts with the Contros 5 Casts with the Contros – 3 with pump cowling – 1 with no pump cowling – 1 with pump operational – 3 with bottles & GC work 4 separate Mass Spec casts 4 separate Mass Spec casts 4

5 CTD Cast 13 With CDOM & O2

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8 Detection Chamber Readings Control Temperature Control Temperature Gas Temperature Gas Temperature Pressure Pressure Relative Humidity Relative Humidity Raw electrical signal Raw electrical signal

9 CAST 13 Raw Voltage Output

Depth Profile – Cast 13 IR raw output 10 Down CastUP Cast

Depth Profiles Mass Spec Casts 11 Cast 1 Cast 2 Cast 3

Future Directions AUV Surveys – Mid-Atlantic Ridge Geochemical Array - BBLA – Duty cycle vs reconfigure power draw – Post deployment follow up Sensor development – Shorten response time – Lower detection levels 12

Funding for this project is generously provided by 13 NOAA/OER, NIUST DOI/BOEMRE (MMS) and DOE/NETL Special thanks to Andy Gossett, Matt Lowe, Brian Noakes, Larry Overstreet and the crew of the Pelican for handling the at-sea operations of the equipment