42MINING
People need to dig up the
resources from the Earth’s crust
before they can use them. This
is called mining. There are two
main techniques, depending
on the types of mineral being
extracted. They are surface
mining, or quarrying, and
underground mining.Surface mining The largest mines
are strip mines, which extract
minerals on or near the Earth’s
surface. Miners use explosives,
diggers, and heavy machinery to
dig huge holes in the ground.
Most of the world’s mining output
is through surface mining. This
type of mining is much safer
than underground mining. IRON MINE
Iron ore mines in
Brazil are some of
the most productive
in the world.Riches from the Earth
Many useful materials are hidden away below the
Earth’s surface. Some of these rich resources, such
as precious metals and gemstones, have been used
since ancient times. Others, such as fossil fuels, are
more recent discoveries, but equally important.
O South Africa is one of the world’s
leading mining nations, holding large
reserves of gold, diamonds, and other
valuable mineral resources.
O By 2015, the world demand for oil will
be about 96 million barrels a day.
O Saudi Arabia is the world’s
leading oil producer.
O Mining kills and injures more
workers than any other industry.FAST FACTS
EARTH
DRILLING FOR GOLD A miner
drills for deposits of gold at a mine in
South Africa. The rock face lies deep
underground, and the work is physically
demanding and very dangerous.Underground mining Any minerals
buried deep beneath the Earth’s
surface must be extracted using
underground mining techniques.
Miners use heavy machinery to drill
deep shafts under the ground. They
lay rails to carry the minerals, drilling
gear, waste material, and the miners
themselves to and from the rock face.
Underground mining is dangerous
work and much more expensive than
surface mining. HEMATITE,
the mineral form
of iron oxide, is
identified by its
rusty red streaks.