Environmental Engineering Reference
In-Depth Information
There is a deep divide between geologists and economists over trying to answer the
question of how much oil, gas, coal, or uranium the Earth's crust holds.
An increasing number of resource geologists expect the production of oil re-
sources to end in the not so distant future, that is, over the next 10-20 years. The
geologists base their projections on the fact that oil must first be found before it
can be produced. The heydays of large oil discoveries (“super giants”) ended in
the mid-1960s, followed by a substantial decline in the discovery of new reserves
globally. Between 1980 and 2007 only 82% of global oil production was replen-
ished by new oil reserve additions.
Continuously producing more oil without locating new reserves will eventually
result in peak oil production at the approximate time when half of the oil reserves
have been produced. After the peak is reached, the global availability of oil will de-
cline year after year at a rate that depends on the rate of production. Therefore, the
assumed ultimate global oil reserve endowment is a critical parameter in determ-
ining both the level of peak production and the point in time when the peak will
occur. Estimated recoverable oil has routinely been calculated since the mid 20th
century from the world's original endowment of conventional oil. The approxim-
ately 100 different estimates cover a wide range, especially those made during the
1970s. The majority, however, lie in the 12.6-16.7 zetajoule (ZJ) bracket. By the
end of 2008 cumulative oil production amounted to some 6.5 ZJ (156 Gtoe). Go-
ing by the lower estimates, we have almost reached the half-way production mark
(the peak), and production is bound to decline from here on out. Using the higher
estimates would only shift the peak by a decade or so.
The term “recoverable” is not a definite measurement for “oil-in-place” but only
the portion that is recoverable because of geological complexities and econom-
ic limitations. One technology for mining more oil is enhanced recovery (EOR),
which is applied to extract residual amounts of oil that otherwise would not reach
the surface. Another one is offshore extraction at increasingly deeper depths, where
the oil is sometimes covered by very tricky salt deposits.
Economists believe that technological innovation will continue to allow explor-
ation of additional reserves not currently identified, or not economically extract-
able with existing technology. Higher prices not only push the frontier of mar-
ketable resources (smaller field, higher recovery rates, more challenging environ-
ments, etc.) but stimulate upstream technology and R&D in exploration and pro-
duction.
