© REGION 4 EDUCATION SERVICE CENTER. ALL RIGHTS RESERVED.
Unit 5: Earth and Space, Part 2
Lesson 3: Alternative Energy Resources
© REGION 4
EDUCATION
SERVICE CENTER. ALL RIGHTS RESERVVED.
mantle
crust
outer core
inner core
Y ou have already learned that fossil fuels are—
natural resources
found in sedimentary rock formations deep inside Earth’s
crust
major sources of energy
It may seem that our natural resources will never run out. There
always seems to be electricity to use and fuel for cars. The
fact, however, is that some natural resources are being used at
a rate greater than the rate at which they can be renewed. This
type of natural resource is called nonrenewable.
Since fossil fuels are formed over long periods of time and
are not easily replaced, they are considered nonrenewable
resources.
