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Chapter One
HOW COAL
FORMED
C
oal, like natural gas and petroleum
oil, is a resource known as a
fossil
fuel
. It formed millions of years
ago from the remains of living things,
altered and preserved deep in the ground.
This happened especially during the
Carboniferous period, from 359 to 299
million years ago. The time span is named
after its
carbon
-rich remains (carbon is
the main substance in coal).
anaerobic:
occurring without
oxygen.
bituminous:
containing the
thick, sticky, dark, tarry
substance called bitumen
or asphalt.
carbon:
a pure chemical
substance or element found
in great amounts in living
and once-living things.
macerals:
microscopic
particles or units in coal,
made from the changed,
fossilized remains of plants.
reserves:
amounts in store,
to be used in the future.
stagnant:
inactive or stale.
9
Words to Understand