Salinity-induced hydrate dissociation: A mechanism for recent CH4 release on Mars

Recent observations of CH4 in the Martian atmosphere suggest that CH4 has been added relatively recently. Several mechanisms for recent CH4 release have been proposed including subsurface biological methanogenesis, abiogenic hydrothermal and/or volcanic activity, dissociation of CH4 hydrates, atmosp...

Full description

Saved in:
Bibliographic Details
Published in:Geophysical research letters 2007-06, Vol.34 (11), p.n/a
Main Authors: Elwood Madden, M. E., Ulrich, S. M., Onstott, T. C., Phelps, T. J.
Format: Article
Language:English
Subjects:
BRINES
DISSOCIATION
Earth sciences
Earth, ocean, space
Exact sciences and technology
FLUCTUATIONS
Gas hydrate
GAS HYDRATES
GEOTHERMAL ENERGY
GEOTHERMAL GRADIENTS
hydrate
HYDRATES
Mars
methane
PHOTOLYSIS
SALINITY
STABILITY
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Recent observations of CH4 in the Martian atmosphere suggest that CH4 has been added relatively recently. Several mechanisms for recent CH4 release have been proposed including subsurface biological methanogenesis, abiogenic hydrothermal and/or volcanic activity, dissociation of CH4 hydrates, atmospheric photolysis, or addition of organics via bolide impact. This study examines the effects of increasing salinity on gas hydrate stability and compares estimates of the Martian geothermal gradient to CH4 and CO2 hydrate stability fields in the presence of high salinity brines. The results demonstrate that salinity increases alone result in a significant decrease in the predicted hydrate stability zone within the Martian subsurface and may be a driving force in CH4 hydrate destabilization. Active thermal and/or pressure fluctuations are not required in order for CH4 hydrates to be the source of atmospheric CH4.
ISSN:0094-8276
1944-8007
DOI:10.1029/2006GL029156