Page 175 - (DK) I Can’t Believe It! 2

IT CAN’T BE TRUE! 173

FAST FACTS
The Mponeng
elevator Oil reserve
travels at
46 ft (14 m) per Sea of Okhotsk
second but it
still takes an
hour to take
workers to
the bottom Kola is still the world’s deepest
of the shaft. borehole, but it is no longer the
longest. In 2012, Exxon drilled
an oil well 40,604 ft (12,376 m)
long. Parts of it run horizontally,
however, so it is not quite as deep.

Vostok station
Mponeng Gold
Mine in South Ice sheet Lake Vostok
Africa is the
world’s deepest,
at more than Bedrock
2.4 miles (4 km).
The mine has In 1989, Russian scientists
about 236 miles began a project to drill through
(380 km) of 2 miles (3 km) of Antarctic ice to
tunnels worked reach Lake Vostok, a freshwater
by 4,000 miners. lake that had lain sealed under the
ice for more than 15 million years.
In 2012, the scientists reached
their goal.
South
Africa Mponeng miners are
the humans who have
traveled deepest into
the Earth. The rock face in
these lowest passageways
can reach 140°F (60°C),
so the mine shafts are Continental crust Oceanic
air-conditioned to a crust
safe temperature.
Upper mantle
Scientists almost broke through
The Kola borehole project the crust where is it very thin, at
aimed to reach the boundary less than 3.4 miles (5.5 km), in
between the Earth’s crust and the ocean off Costa Rica. Oceanic
mantle. Although the borehole crust is always thinner than
penetrated less than a third of continental crust, which forms
the crust, it reached rocks more the Earth’s landmasses and is
than 2.5 billion years old. 15–45 miles (25–70 km) thick.
Russia

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