Minerals Report - International Seabed Authority

Table 8. Estimates of methane gas and methane carbon resource contained in
continental and marine gas hydrate accumulations (modified from Kvenvolden, 1993,
by Prensky, 1995).
Methane gas
m3 x1015 Methane gas
Tcf x 105 Methane carbon
kg x 1015 Reference
Oceanic sediments
3.1 1.1 1.7 McIver (1981)
5-25 1.8-8.8 2.7-13.7 Trofimuk et al. (1977)
7600 2700 4100 Dobrynin et al. (1981)
17.6 6.2 11 Kvenvolden (1988)
19.5 6.9 11 MacDonald (1990)
26.4-139.1 9.3-49.1 ---- Gornitz and Fung
(1994)
Continental sediments
0.014 0.005 7.5 Meyer (1981)
0.057 0.011 17 McIver (1981)
0.057 0.02 31 Trofimuk et al. (1977)
34 12 1800 Dobrynin et al. (1981)
---- ---- 400 MacDonald (1990)
Although considerable uncertainty exists about the total gas resource
potential of hydrates, it is clear that the oceanic potential is far greater than the
continental one.
The know locations of gas hydrates is very likely to underestimate the
total world wide occurrence. From considerations of the stability condition for
hydrate, it is likely to occur everywhere that the seafloor exceeds 500 m (or
300 m in high latitudes), and where there is a source of unoxidsed organic
carbon in marine sediments. The greater the thickness of marine sediments,
the greater the likelihood of there being suitable source material for the
production of biogenic methane (the key fuel element in gas hydrates).
IINTERNATIONAL SEABED AUTHORITY 731