ABSTRACT: Geologic constraints on the influence of gas hydrates on Holocene climate change.

CGRG Bibliography of Canadian Geomorphology
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A number of researchers have suggested that past periods of abrupt climate change may have been triggered, or enhanced, by the catastrophic release of methane gas to the atmosphere from dissociating gas hydrates. This talk will assess the stability of various gas hydrate deposits during deglacial conditions or possible conditions of future climate warming. Key considerations include where and in what abundance do the gas hydrates occur in nature, and how responsive are they to change? Geothermal modeling suggests that most classic marine and terrestrial deposits can be expected to take many millennia to respond to temperature forcing alone. This is mainly because of the slow rate of downward-propagating heat flow, and the thermodynamics of the gas hydrate dissociation process itself. However, there are certain environments where geologic processes may have pre-conditioned gas hydrate creating significant potential for instability. These areas include transgressive arctic coasts, areas affected by abrupt changes in glacial loading, or shallow gas hydrates in permafrost and marine environments. Conditions could possibly exist in these areas for point sources where abrupt events with significant methane release could occur, or alternatively where more widespread regional release of methane may occur. While recent work points to areas for future research, it is an unfortunate reality that in terms of gas hydrates and climate change, the unknowns out weigh the knowns. Our knowledge of the natural abundance of gas hydrate is very limited as is our knowledge of the systematics of methane in the geosphere, including migration mechanisms and flux rates to the atmosphere.

Bibliography of Canadian Geomorphology