Geology Reference
In-Depth Information
where R = natural resources, E = energy, I = Ingenuity,
and P = Population sharing those resources. A resident
of the U. S. will use more than 2 million pounds of
minerals in his or her lifetime, almost half of which
will be aggregates (gravel and crushed stone).
We are very near the peak in oil production in the
Fossil Fuel Age, living on buried sunlight. The degree
of dependence on fossil fuels by the U.S. is readily seen
with the mix of energy we now use. For example the
average of July 2003 and January 2004 U.S. energy con-
economic that there will not be a limit to supply. Another
view is that many resources are exhaustable, and it is
not wise to rely on expected new discoveries. Ulti-
mately, as vividly illustrated by Apollo mission pho-
tographs of Earth as a sphere in space, most resources
are limited.
There was a $10,000 wager between opposing
camps in the concern for mineral resources. In the
"cornucopian" camp (mineral resources will be avail-
able) the late Julian Simon, an economist at the Univer-
sity of Maryland, declared in the 1980s that in ten
years there would be no shortages or major increases
in costs for mineral commodities. Paul Ehrlich, a pop-
ulation biologist at Stanford in the "sustainability"
camp, said there would be shortages or price increases.
Ehrlich lost the bet. However, will this condition con-
tinue? In 1968, Preston Cloud suggested that the cor-
nucopians had five premises on which their lack of
concern for mineral resource availability was based:
(1) cheap inexhaustible nuclear energy, (2) economics
as the major factor in resource availability, (3) uninter-
rupted variation from ore to natural crustal abun-
dance, (4) assumed population control, and (5) a
technological fix.
Resource availability is impacted by environ-
mental and social concerns. In the 1990s an environ-
mental conscience began to spread globally in the
mining world and formal guidelines were proposed
for the mineral production sector. At least one example
of much delayed mine development by a major min-
ing firm can be traced to inappropriate assessment of
environmental and social impacts and poor public
relations. Environmental concerns must include
impacts of exploration, removal or mining, processing,
manufacturing and transportation, resource use, and
post-resource-use waste management. Poor waste
management results in direct (waste) or indirect (pol-
lution) loss of resources.
The modern viewpoint is that wastes are
resources out of place. Urban ore, the mineral resource
values concentrated by humans in their landfills, can
be recycled and reused. In some cases the "deposits"
in landfills are richer than the mineable virgin mineral
deposits.
For any finite nonrenewable mineral resource,
we should understand the nature of extraction of that
resource over time. "Hubbert's Bubble" (Figure IV.2)
shows the actual and forecast production curves for
world oil. Depletion of any nonrenewable mineral
resource, from a mining district or from a country, fol-
lows a similar trend.
sumption amounted to 8.85
X
10
1
5
Btus with petro-
leum accounting for 38%, natural gas for 24%, coal for
24%, hydroelectric and other renewables for 5.7%, and
nuclear power for 8.3%.
Hubbert (1969) and others have documented the
change over time of our fossil fuel use. Against a scale
of 10,000 years of human history, our use of fossil fuel
shows as a "blip." In the 1950s Hubbert forecast the
decline in U.S. oil production, which began in 1970. We
now import more than 60% of our crude oil. The global
peak and decline in production of conventional oil is
occurring now (Simmons, 2005; Strahan, 2007; Zwicker
and others, 2004).
Alternative, particularly renewable, energy
resources are the key to sustainability. Fossil fuel use
will decline over the next 30 to 40 years due to avail-
ability and its impact on local and global environ-
ments. Solar energy will grow in importance. It will be
used directly as heat or as electricity derived by heat or
photovoltaics, wind energy, ocean currents, ocean
thermal gradients, or biomass. Nuclear fusion is not
expected to be a factor in the near future but could
play a very important role if attained; nuclear fission
might be one option to counteract global warming by
CO2 from fossil fuels, and this industry is showing
signs of recovery. Deep geothermal energy (not
groundwater heat pump systems heated mainly by
solar energy) is another alternative energy source that
could become more important. For many remote local-
ities, photovoltaic cells are providing viable alterna-
tives to connections to an electric grid. In developing
countries, photovoltaics will provide major improve-
ments in the quality of life and sustainability without
construction of centralized power plants and distribu-
tion systems.
GEOLOGIC RESOURCE AVAILABILITY
Given the importance of mineral and energy
resources, it is understandable why so many commis-
sions in the 20th century explored their availability
and expected lifetimes. Two philosophical views about
mineral resources are common. One view is that the
supply of mineral resources is not a problem. Minerals
will either be replaced by something else if they run out
or an increase in price will make so many resources
QUESTIONS IV, INTRODUCTION
1.
What is a geologic resource, according to the discussion in
Geologic Resources?
