Constraining the global inventory of methane hydrate in marine sediments

• Main Authors: Wallmann, Klaus, Burwicz, Ewa, Ruepke, Lars H., Marquardt, Mathias, Pinero, Elena, Haeckel, Matthias, Hensen, Christian
• Format: Book Part
• Language: English
• Published: HWU 2011
• Subjects: Methane hydrate
• Online Access: https://oceanrep.geomar.de/id/eprint/12473/; https://oceanrep.geomar.de/id/eprint/12473/1/Wallmann2011ICGHProc129.pdf

The accumulation of methane hydrate in marine sediments is basically controlled by the accumulation of particulate organic carbon at the seafloor, the kinetics of microbial organic matter degradation and methane generation in marine sediments, the thickness of the gas hydrate stability zone (GHSZ), the solubility of methane in pore fluids within the GHSZ and the ascent of deepseated pore fluids and methane gas into the GHSZ. Our present knowledge on these controlling factors is discussed and new estimates of global sediment and methane fluxes are presented. A new transport-reaction model is applied at a global grid defined by these up- dated parameter values. The model yields an improved and better constrained estimate of the global inventory of methane gas hydrates in marine sediments (3000 ± 2000 Gt of methane carbon).