Download Unit C: Earth Science Chapter 1: The Changing Earth Lesson 1

Unit C: Earth Science
Chapter 1: The Changing Earth
Lesson 1: Layers of the Earth
1. Atmosphere is the layer of gases that surrounds the
planet
2. Clouds are in this layer
3. Atmosphere contains gases that organisms, need to live
4. Most of the atmosphere is close to the surface of the
earth
Hydrosphere is the layer beneath the atmosphere: it is the water
part of the earth's surface
1. It includes oceans, lakes, rivers, streams, and
glaciers
2. Water covers 75% of the earth's surface
3. Without water life could not exist
Lithosphere is the solid surface of the earth it includes the
continents and the ocean floors
1. Our homes are attached to the lithosphere
2. The atmosphere, hydrosphere, and lithosphere form
layers, but parts of each layer can be found in others
Crust, Mantle, Core
1.
Crust: earth's outer rock layer
2.
Mantle: is the rock layer beneath the crust the Upper
part of the mantle is solid
3.
The middle portion of the mantle is partly melted
4.
The lower portion of the mantle is solid and can flow
slowly
5.
Core: the center part of the earth made of iron and
nickel
6.
In the outer part of the core, the iron and nickel are
melted
7.
As you go deeper into the outer part of the core the
temperature continues to rise
8.
As you go deeper more of the earth is above you and the
pressure is so great it forces the iron and nickel to become
solid
Lesson 2
How Does the Earth's Crust Move?
Moving Continents
1. Scientist think the continents were once part of a single land
mass that began separating 150 to 200 million years ago
2. Evidence that supports the continents were once
connected:
3. Mountain ranges on five continents fit together in a
jigsaw puzzle and ancient rock formations of these
mountains match
4. Coal deposits in North America match identical
deposits in Europe
5. Discovery of warm-weather organisms in cold
climates
6. Glacial deposits in warm climates
Plate Tectonics
1. This is the theory of how continents move
2. The earth's surface is broken into about twenty sections or
plates
3. Plates are large sections of the earth's surface made of
the crust and the top rigid portion of the mantle
4. They fit together but keep changing because they are slowly
moving
Events Caused by Plate Movements
1. Earthquakes
2. Volcanic Eruptions
3. Mountain Formations
4. These events are most common along plate boundaries
Lesson 3
What Changes the Earth's Surface?
Weathering
1. Weathering is the process that breaks down and changes
rocks
2. Rocks can slowly be broken down by air, ice, water, chemicals,
and living things
3. There are two types of weathering
4. Physical Weathering: breaks down rock without changing the
substance that makes up the rock
5. Can be caused by freezing water, waves, windblown
particles, and plant roots
6. Chemical Weathering: breaks down rock by changing the
substance that makes up the rock
7. Water combines with chemicals such as weak acid to cause
chemical weathering
8. Air pollution and living things can cause chemical
weathering
Erosion
1. Erosion is the process of moving weathered rock and soil by
wind, water, and ice
2. Flowing water is main cause of erosion
3. Wind can also cause erosion
Deposition
1. Deposition is the dropping of materials moved by
erosion
2. Over time deposition may build new features such as:
deltas, beaches, and dunes
Lesson 4
How Do Rocks Reveal Changes on the Earth?
How Rocks Change Form
1. Rocks can be heated, compressed, cemented, twisted
and even melted
2. These changes that rocks go through make up the rock
cycle
3. Igneous rocks are rocks formed from melted mantle that
comes from deep inside the earth when it cools the melted
material hardens into igneous rock
4. Metamorphic rock is formed by the application of heat and or
pressure to sedimentary rock or igneous rock
5. Sedimentary rock is formed by the pressing and the
cementing of layers of sediments
6. Most rocks are made of one or more minerals
7. A mineral is a natural, nonliving solid with a definite chemical
structure
8. Different minerals have different properties including:
color, luster, hardness, magnetism, crystal pattern, and
breakage pattern
9. The Mohs Hardness Scale measures the hardness of minerals
Fossils That Indicate Changes
1. A river carries sediments into a shallow sea and deposits
them on the bottom. Layers build up.
2. Dead animals sink to the bottom. Layer after layer of
sediments are deposited on top.
3. Over time, the lower layers form sedimentary rock. The
remains of the dead animals form fossils.
4. Fossils in rock layers tell about changes in the earth's climate
and land features.