1

Contros HydroCMethane Sensor

at MC118

Presented by Ken SleeperSeabed Technology Research Center

Mississippi Mineral Resources InstituteUniversity of Mississippi

October 26, 2010

2

Why Contros

• 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• Rich Camilli redesign of the power draw –

Observatory Mode

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Contros near IR CH4 sensor

Key Features

• Membrane Diffusion• Partial Pressures (Henry’s Law)• IR absorption bands of Methane• Concentration• Pressure• Temperature• Relative Humidity

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June 2010 MC118 Cruise

• 15 CTD CASTS with CDOM and Transmissometer

• 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

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CTD Cast 13With CDOM & O2

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9:58:39 10:03:5910:09:1810:14:3810:19:5810:25:1810:30:380

0.5

1

1.5

2

2.5

3

3.5

4

62310 Cast 11Concentration µmol/L

Concentration µmol/L

10:49:4810:55:0811:00:2811:05:4811:11:0811:16:2811:21:4811:27:0811:32:280

0.5

1

1.5

2

2.5

3

62310 Cast 12Concentration µmol/L

Concentration µmol/L

7

13:15:08 13:17:48 13:20:28 13:23:08 13:25:48 13:28:28 13:31:08 13:33:48 13:36:28 13:39:08 13:41:48 13:44:28 13:47:08 13:49:48 13:52:28 13:55:080

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

062410 cast 13Concentration µmol/L

Concentration µmol/L

8

13:15:0813:19:2313:23:3813:27:5313:32:0813:36:2313:40:3813:44:5313:49:0813:53:23900

950

1000

1050

1100

1150Pressure

TIME (hr:min:sec)

Pres

sure

(mba

r)

13:12:00 13:19:12 13:26:24 13:33:36 13:40:48 13:48:00 13:55:12 14:02:2425

27

29

31

33

35

37

39

41

Gas Temperature (°C)

CH4-0510-006 CH4-0510-006 T_gas °C

Tem

pera

ture

Time (hr:min:sec)

13:12:00 13:19:12 13:26:24 13:33:36 13:40:48 13:48:00 13:55:12 14:02:240

10

20

30

40

50

60

70Relative Humidity (rh%_gas%)

CH4-0510-006 CH4-0510-006 %rH_gas %

Rela

tive

Hum

idity

(%)

Time (hr:min:sec)13:15:0813:19:0313:22:5813:26:5313:30:4813:34:4313:38:3813:42:3313:46:2813:50:2313:54:18

00.20.40.60.8

11.21.41.61.8

2

062410 cast 13Concentration µmol/L

Concentration µmol/L

Time (hr:min:sec)

Conc

entr

ation

13:15:0813:19:2313:23:3813:27:5313:32:0813:36:2313:40:3813:44:5313:49:0813:53:2339.2

39.4

39.6

39.8

40

40.2

40.4

40.6

40.8

41Control Temperature (°C)

Time (hr:min:sec)

Tem

pera

ture

(°C)

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

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CAST 13 Raw Voltage Output

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Depth Profile – Cast 13IR raw output

Down Cast UP Cast

Depth ProfilesMass Spec Casts

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Cast 1 Cast 2 Cast 3

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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

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Funding for this project is generously provided by

NOAA/OER, NIUSTDOI/BOEMRE (MMS)

andDOE/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