TY - JOUR
KW - 1615 Global Change: Biogeochemical cycles
KW - processes
KW - and modeling (0412
KW - 0414
KW - 0793
KW - 4805
KW - 4912)
KW - 3002 Marine Geology and Geophysics: Continental shelf and slope processes (4219)
KW - 3004 Marine Geology and Geophysics: Gas and hydrate systems
AU - Angus Best
AU - Michael Richardson
AU - Bernard Boudreau
AU - Alan Judd
AU - Ira Leifer
AU - Anthony Lyons
AU - Christopher Martens
AU - Danial Orange
AU - Simon Wheeler
AB - Abnormally high levels of methane gas in seafloor sediments could pose a major hazard to coastal populations within the next 100 years through their impact on climate change and sea level rise. Marine scientists have known for many years that biogenic methane (CH<sub>4</sub>) is generated in shallow seabed sediments on continental margins, especially in rapidly deposited muddy sediments with high organic matter content (see Methane Flux Control in Ocean Margin Sediments (METROL) project in Mienert et al., [2004]).Gassy sediments are found in river deltas, estuaries, and harbors, but also in deeper waters on continental shelves and slopes. Human activities can accelerate natural seafloor gas generation by increasing the supply of sediments and organic matter from rivers through deforestation and intensive farming, and also by the disposal of human waste at sea. When this extra organic matter becomes buried to about one meter beneath the seabed, biogeochemical processes start to convert it to CH<sub>4</sub> [Floodgate and Judd, 1992]. The impact of this extra CH<sub>4</sub> could be felt within the next 100 years, assuming a one-centimeter-per-year sediment accumulation rate.
BT - Eos Trans. AGU
M1 - 22
N2 - Abnormally high levels of methane gas in seafloor sediments could pose a major hazard to coastal populations within the next 100 years through their impact on climate change and sea level rise. Marine scientists have known for many years that biogenic methane (CH<sub>4</sub>) is generated in shallow seabed sediments on continental margins, especially in rapidly deposited muddy sediments with high organic matter content (see Methane Flux Control in Ocean Margin Sediments (METROL) project in Mienert et al., [2004]).Gassy sediments are found in river deltas, estuaries, and harbors, but also in deeper waters on continental shelves and slopes. Human activities can accelerate natural seafloor gas generation by increasing the supply of sediments and organic matter from rivers through deforestation and intensive farming, and also by the disposal of human waste at sea. When this extra organic matter becomes buried to about one meter beneath the seabed, biogeochemical processes start to convert it to CH<sub>4</sub> [Floodgate and Judd, 1992]. The impact of this extra CH<sub>4</sub> could be felt within the next 100 years, assuming a one-centimeter-per-year sediment accumulation rate.
PB - AGU
PY - 2006
SN - 0096-3941
T2 - Eos Trans. AGU
TI - Shallow seabed methane gas could pose coastal hazard
UR - http://dx.doi.org/10.1029/2006EO220001
VL - 87
ER -