Concentrations of dissolved gases at a methane seep in the deep northern Gulf of Mexico measured with an in situ mass spectrometer (ISMS)

Concentrations of dissolved methane, hydrogen sulfide, carbon dioxide and oxygen in a Bathymodiolus mussel bed at a methane seep in the deep northern Gulf of Mexico. The data were collected with an in situ mass spectrometer (ISMS) on May 6, 2015, during a research cruise with RV Nautilus, dive H1423. The location was site MC853, at 28.12835 (lat), -89.14100 (long), in 1080 m water depth. At this site the two mussel species Bathymodiolus brooksi and B. childressi were collected. ISMS measurements were performed before and after the removal of animals from the mussel bed.