CHAPTER 1 SECTION 1

EARTH’S INTERIOR

1.GEOLOGIST-scientists who

study the forces that make and shape planet

Earth.

2. Geologists study:-CHEMICAL and PHYSICAL

characteristics of rock - MAP where different types of

rock are found- describe LANDFORMS

- study the processes that CREATE Earth’s features and

search for clues about EARTH’S HISTORY.

3. ROCK – the material that forms

Earth’s hard surface

4. GEOLOGY – the study of planet

Earth

5. Geologists have concluded that

Earth’s landforms are the result of

NATURAL FORCES that slowly build

up and WEAR DOWN the land.

6. Geologists divide the forces that change the surface into two

groups:CONSTRUCTIVE FORCES – forces

that build up mountains and landmasses

DESTRUCTIVE FORCES – forces that slowly wear away mountains

and other features on the surface.

7. Give one example of a constructive force and one example of a destructive

force

8. CONTINENT – a great landmass surrounded by

oceans.

9. Why would a geologist study the interior of a

cave?

TO STUDY MATERIALS THAT ARE NORMALLY UNDERGROUND

10. The EXTREME CONDITIONS of Earth’s

interior prevent exploration far below the

surface.

11. Geologists must rely on

INDIRECT methods of observing

Earth’s interior.

12. SEISMIC WAVES – waves

produced when

earthquakes occur.

13. The SPEED of seismic waves and the PATHS they take reveal how the planet

is put together.

14. How is the earth like an onion?

IT HAS LAYERS

15. As you go deep toward the center of the Earth TEMPERATURE and PRESSURE increase.

16. PRESSURE – the force pushing on a surface or

area.

17. Three main layers make up Earth’s interior:

A. CRUST – a layer of rock that forms Earth’s outer skin.

- It includes both the dry LAND (where it is thickest

under MOUNTAINS) and the OCEAN floor (where it is

thinnest)

- OCEANIC CRUST – crust beneath the ocean. It

consists mainly of dark, dense rocks called BASALT.

- CONTINENTAL CRUST –crust that forms the continents. It consists mainly of light colored less dense rock

called GRANITE.

B. MANTLE – the layer of hot solid rock, located under

the crust.

- LITHOSPHERE – the rigid layer consisting of the uppermost part of the mantle and the crust

together (lithos means “STONE”)

- ASTHENOSPHERE – the soft part of the mantle located just below the lithosphere (asthenos means “WEAK”).

- The LITHOSPHERE floats on the ASTHENOSPHERE.

C. The core consists of two parts.

- OUTER CORE – the liquid

layer of molten

metal – it behaves

like a thick liquid.

- INNER CORE – a dense ball

of solid metal.

The metals IRON and NICKEL make up both

parts of the core.

- The inner and outer cores together are just slightly smaller than the MOON, yet they make up about 1/3 of the Earth’s mass.

18. CURRENTS in the liquid outer core force the solid inner core

to spin at a slightly FASTER rate than the rest of the planet.

These currents in the outer core create Earth’s MAGNETIC FIELD.