Earth's Layers
Scientists who study the earth's
layers are called geologists. Since they cannot see the inside of the
earth they use geographical clues to help them. These clues are gathered
from activities such as volcanoes and earthquakes. From these clues
geologists hypothesize (make an educated guess) what they think the earth
actually looks like.
Geologists
believe the earth is neither liquid nor solid all the way through. It is
a made up of different layers. Some of these layers are solid. Some
are liquid, and some are both. The layers of the earth have special
names. They are the crust, the mantle, and the core. These layers
vary in width and temperature. Look at the picture below.
The thin
crust, or outer layer of the earth is made mostly of rock. The thickness
of this layer varies from 3 to 34 miles. Below the crust is the
mantle. The mantle is about 1,800 miles thick and made mostly of solid
rock. It is the thickest layer of the Earth. The mantle is also very hot
- about 5,400 degrees F in some spots. The center of the earth is called
the core. It is about 2,200 miles thick. The core is extremely hot
- about 7,200 degrees F. The core is further divided into an inner core
and an outer core. The outer core is a liquid layer of melted nickel and
iron. The inner core is made of solid nickel and iron.
Directions: Answer
the questions about the inside of the earth.
1. A
scientist who studies the earth is called a .
2. To
hypothesize means to
read
make a guess
make an educated guess
cut apart and observe
make a guess
make an educated guess
cut apart and observe
3. The
thin outermost layer of the earth is called the.
4. The
layer below the thin outermost layer is called the .
5. The
center of the earth is called the .
6. The
layers of the earth vary in width and .
crust
mantle
core
mantle
core
8. Which
of the following statements is true?
The
mantle of the earth is made of solid nickel and iron.
The crust of the earth is made of solid nickel and iron.
The inner core is made of solid nickel and iron.
The crust of the earth is made of solid nickel and iron.
The inner core is made of solid nickel and iron.
9. The is the
thinnest part of the earth.
10. The is the
thickest part of the earth.
(adapted
from http://www.myschoolhouse.com/courses/O/1/69.asp)
