Environmental Engineering Reference
In-Depth Information
contained just over 60% of the world's crude oil reserves,
and Saudi Arabia alone more than 20%. Discoveries of
giant fields have become rare, and new reserves will have
to come from smaller continental finds and from offshore
areas that may contain as much as 40% of the world's
undiscovered oil.
The Persian Gulf-Zagros Basin will remain an
astounding singularity. Two supergiant oil fields, the
Saudi al-Ghaw¯r with reserves of at least 550 EJ and
the Kuwaiti al-Burk¯n with at least 470 EJ, will retain
their position as the world's largest oil reservoirs (fig.
8.3). The Cantarell complex in Mexico and Venezuela's
Bolivar rank third and fourth, followed by Saf
¯
n
¯
ya-Khafj
¯
near the Saudi-Kuwait border. Of the world's ten largest
natural gas fields, eight are in Russia. The Urengoy field
in Western Siberia, discovered in 1966, producing since
1978, and holding some 270 EJ of reserves, is unlikely
to be surpassed as the world's largest natural gas deposit.
Its neighboring Yamburg field and Orenburg field in the
Volga Basin rank second and third.
Resources in place in any small hydrocarbon fields pro-
rate to less than 1 GJ/m
2
, and extensive giants such as
Hugoton-Panhandle in Texas or Alberta's Pembina have
less than 10 GJ/m
2
. The richest fields contain 10
1
-10
2
GJ/m
2
. Prudhoe Bay rates about 25 GJ/m
2
; the Alge-
rian Hassi Messaoud, 35 GJ/m
2
; the Saudi al-Ghaw¯r,
originally 100 GJ/m
2
; California's Wilmington, 200
GJ/m
2
; California's Ventura-Rincon, 300 GJ/m
2
, and
the Kuwaiti al-Burk¯n, more than 1 TJ/m
2
. The Green
River formation, the world's largest concentration of oil,
interspersed in the shales of Colorado, Utah, and Wyo-
ming, has a total energy content rivaling al-Burk
¯
n's den-
sity, but deposits of richer shales yielding 100-400 L/t
of rock prorate to no more than 185 GJ/m
2
(Dinneen
and Cook 1974). The extraordinarily high energy cost
8.3 Major supergiant and giant oil fields in the world's
richest oil province, the Persian Gulf-Zagros Basin. From
Smil (2003).
of extracting liquid fuel from these rocks makes it highly
unlikely that this will be a commercial source of oil.
The total bitumen content of Canada's oil sands pro-
rates to about 100 GJ/m
2
, and the ultimately recover-
able share has an energy density of nearly 13 GJ/m
2
.
Only about 20% of the recoverable share could
be reached by surface mining; the rest would have to be
extracted in situ. The first operation of this kind, Im-
