Water and brine samples were taken for CH
concentration measurements.
Immediately after the water rosette was on deck the water was transferred
into 1 liter glass bottles which subsequently were degassed onboard using
an ultrasonic vacuum system [Schmitt et al.(1991)], Fig.11.
The dissolved gas is stored in gas-tight 25 ml glass vials for land-based
analyses of hydrocarbon concentrations using a gas
chromatographic system followed by mass spectrometric analyses of stable
carbon and hydrogen isotope compositions [Faber (1998)]. The results
will be used to quantitatively describe CH exchange across the brine
seawater interface and recognize hydrocarbon oxidation processes.
A parallel brine sample of selected depths was degassed and the gas was
stored to measure the 
C activity of methane at the Leibniz Institute
for Age Dating, Kiel.
figure
