5th Grade Earth Science

Chapter 9Earth’s Changing Surface

What is the Earth made of?

• Landforms on Earth include:– __________– __________ - flat land– ________ - a deep crack– ______ - flatlands with few trees– _______ - on land where mountains are close together– ______ - beneath the ocean, long row of towering

mountains– ________ - long narrow canyons in the ocean floor

MountainsPlateausGorgesPlainsvalleys

Ridges

Trenches

Earth’s Layers

• The Earth is composed of three distinct layers:1. ______ - outermost solid layer of the Earth.

- The part of the Earth where life is sustained- This layer includes _____and _____ that covers the

surface- The crust is covered by _______ and dry _______- The thickness of the Earth’s crust varies

Crust

soil rock

ocean land

Earth’s Crust

The Mantle

• 2. The _______ - is the layer of Earth just below the Earth’s crust.– This layer contains most of the Earth’s _______ -

the amount of matter in an object– The outer part of the mantle closes to the crust is

_____– The inner part of the mantle furthest from the

crust is made of rock that is so hot that it can _____ very slowly.

Mantle

mass

solid

flow

Structure of the Earth

The Core

• 3. The ____ - the innermost layer of the Earth. The core is made primarily of ______.– This layer is most compact because of all of the

weight above it– The core is divided into two distinct parts:• ___________ - located closest to the mantle. This layer

is so hot that it is liquid• ___________ - located furthest from the mantle and

crust – this layer is solid

core

Outer core

Inner Core

iron

Layers of the Earth

Section Assessment

• Page 265 questions 1-3

Earth’s Plates

• _________ - the Earth’s crust and the upper part of the mantle.– The lithosphere is not a continuous layer it is

made up of pieces called ______________.– The tectonic plates are of varying shapes and sizes

but they all fit together like a puzzle.– Much of the Earth’s lithosphere is under ________

and other bodies of water.– There are ____ major tectonic plates

lithosphere

Tectonic plates

oceans

10

Tectonic Plates

Spreading Ocean Floor

• ____________ - chain of mountains running along the floor of the Atlantic ocean.

• ____________ - A scientist in 1960 claimed that new crust forms at ocean ridges – this explains the existence of trenches and ridges.

• ________ - molten rock, pushes upward from the Earth’s crust. As the magma cools it forms new crust.

Mid-Atlantic Ridge

Henry Hess

magma

What causes Magma to rise?

• As Earth plates move away from each other, the ocean floor spreads apart and new crust rises to fill the gaps.

• What causes the plates to move apart?• __________ - 1930’s when a liquid is heated,

particles speed up and move apart.– ___________ weigh less and float above

____________.

Arthur Holmes

Hot liquidsCooler liquids

Convection

• _________ - as the hot liquid rises and cools it becomes heavier again and sinks, more hot liquid can rise above again – transfer of thermal energy by the movement of a liquid or gas.

• Currents in the ________ constantly rise from the slow flow of the molten rock, circle around and then fall.

• Convection is the _______ that moves the Earth’s plates.

convection

mantle

force

Theory of Plate Tectonics

• ________________ - the _________ is broken into 20 moving plates. – Plates in constant motion and in different

directions.– ____________________ - (GPS) satellites in space

- determine the distance between plates and their change over time.

– This theory explains many of Earth’s features

Theory of Plate Tectonics lithosphere

Global Positioning System

Moving Continents

• Continents move apart• Mountains form where plates move together• As plates move apart, magma may rise to the

surface forming a ________• Oceans may become larger or smaller• Positions of land and oceans has changed and

continues to change from the time of _________ to the __________.

volcano

Pangea Continents

Plate Boundaries

• _____________ - areas where two plates meet.– _________________ - plates move away from

each other • gaps form between the plates• __________________ cause magma to rise between

the gaps• Huge ________ form• Sea floor spreading – ex. _____________________

Plate Boundaries

Spreading boundaries

Convection currents

valleysMid-Atlantic Ridge

Plate boundaries continued

• ______________ - plates slide past each other• _____- break in the Earth’s crust as a result of

fracture boundaries – this can cause _________.

• ______________ - two plates push against each other – one plate might slide underneath the other – towering mountains, deep ocean trenches, earthquakes, and volcanoes can result.

Fracture boundaries

fault

earthquakes

Colliding Boundaries

Boundaries and GPS

Earthquakes

• _________ are caused by the sudden shifting of rock as tectonic plates shift positions– Pressure builds up, rocks lurch forward, and the

Earth’s crust shakes.– ______ - the underground point where the

earthquake occurs– ________ - point on the Earth’s surface directly

above the focus.

Earthquakes

focus

epicenter

Waves

• Energy from the earthquake is carried by _______.

• Waves spread out from the _____ and ________.

• Waves can cause the Earth to move ________, ___________, or in a ___________

• As the waves spread out from the epicenter, they __________.

waves

focus

Lose energy

Up and downBack and forth Circular motion

Volcanoes

Earthquakes and Plate boundaries

• ____________ and _________ have had the most earthquakes because they are located on a ____________ between the Pacific plate and the North American Plate.

• The strength of an earthquake can be measured on a ____________ - a series of numbers that is based on the amount of energy that is released.

California Alaska

Plate Boundary

Magnitude scale

S and P waves

• http://www.thetech.org/exhibits/online/quakes/waves/p&s_waves.htmlDraw a diagram of each

Volcanoes

• __________ occur when magma from the mantle either flows or explodes through the crust.– Opening in the surface of the Earth through which

magma rises– Occur near ______________– Theory of plate tectonics – one plate sinks beneath

another at a plate boundary – sinking crust melts into _______.

– _____ - Magma that reaches the surface

Volcanoes

Plate boundaries

magmalava

Draw and Label Volcanoe page 270-271

Earth’s Features

• Earth’s surface is made up of many different __________.

• Earth’s surface is constantly ________ and so are the landforms

• ___________ - the process of breaking down rock into smaller pieces

• Forces of __________ include ________ and _____

Landforms

changing

weathering

weathering waterice

Mechanical / Chemical Weathering

• _________________ - process of breaking down rock into smaller pieces as a result of ice or water – MINERALS THAT MAKE UP THE ROCK DO NOT CHANGE!

• ________________ - minerals that make up the rock change.

• The cause of chemical weathering is a _________ with something in the environment such as ____ or ________

Mechanical Weathering

Chemical Weathering

reactionwater oxygen

Erosion

• ________ - the process by which soil and sediments are transferred from one location to another

• The movement of soil and sediments can be caused by:– _________– ________– ______– ________

erosion

windwaterice

gravity

Soil Erosion

• Areas of land with no plant covering are susceptible to __________

• __________ - help prevent soil erosion by holding the soil in place

• ___________ - planted by farmers in between harvests to prevent soil erosion and add nutrients to the soil

• ______________ - years of drought and poor farming practices left bare areas of soil

Soil erosion

Plant roots

Cover crops

Dust Bowl of 1930’s

Soil

• ____ - made of weathered rock, air, water, and the remains of living things.

• __________ - process of breaking down rocks through physical factors such as _____, _________, _______ or__________________.

• ________ = non-living parts of the soil• As rock breaks down small pieces collect on

the surface

soil

weathering

frostdrought Changes in temperaturerainwater

inorganic

Soil Formation

• _______ and _______ are plants that help break down rock.

• When rocks are broken down _______are released

• ___________ - dead or decaying matter such as bacteria, fungi, animals and plants.

• ______ - dark colored organic matter formed from decayed plant and animal remains- _______________________

mosses lichens

minerals

Organic matter

humus

Rich in nutrients needed by plants

Layers of Soil

• Soils form in _____ layers• _________- a vertical cross section of the soil

and rock underneath• ________ - first layer of soil, mixture of small

rock pieces, humus, and other organic matter– Most living things are found in the _______– Loose _____________ often covers the topsoil– Rainwater carries minerals from the topsoil to the

2nd layer of soil.

three

Soil profile

topsoil

topsoilOrganic matter

Subsoil / Parent Rock Layers

• _______ - less organic matter than topsoil, lighter in color.

• _________ penetrate the subsoil through rainwater and accumulate

• _________ - third layer, very little organic matter found in this layer

subsoil

mineral

Parent rock

Water

• _________ - solid particles that are moved from one place to another__________ - sediments that form during weathering and erosion are deposited in another location

During the process of deposition, the _______ and ________ of a river’s flow changes

As rivers flow to the oceans they carry ________ and ______________ which are useful to plants and animals to carry out their __________

deposition

sediments

shapedirection

sedimentsDissolved minerals

Life processes

River Systems

• Rivers and streams are _____________ - always moving and changing

• _______ - begins on land that is higher than sea level – ______ pulls the water downward to a lower area

• _____ - streams join until a river is formed• River water wears down soil and rock and

carries their ________ away in different places

Dynamic systems

Streamgravity

river

sediments

Wave Energy

• Ocean waves ________ and __________ a great deal of _________

• Water _______ and _______ in a circular motion

• __________ contained in the waves moves forward

• _________________ interferes with the waves movements – causes waves to slow

carry Pass along

energy

rises falls

energy

Shallower ocean bottom

Waves continued

• Wind Waves are formed when energy is transferred from the ________ to the _______

• ____________ depends on the _________ and how __________ and _____________

• Waves can also be caused by:– ______________– _______________– ______________________

wind water

Size of waves Wind speedLong it blows Distance it covers

tectonic activityVolcanic eruptions

Earthquakes and landslides

Dynamic Systems

• __________ are dynamic systems because the energy from waves has the power to

• _________ also build up beaches by moving sand along the shore

• _________ created when waves move materials from the shoreline to an area away from the shore

• __________ - places where water bodies are separated from the open ocean

beaches

waves

sandbar

lagoons

Beaches

• ________ formed when wind carries sand along the shore - sand builds up into small hills

• ______________are constantly changing as a result of ________ and ______

• _____ and ________ of any beach is determined by the sources of its ______ and _____ - no two beaches are the same!

dunes

Coastal Landforms

wind water

Color texturesand

rock

Section Assessment

• Question 1 on page 278

Section Assessment

• Questions 1-3 page 281

Minerals

• ___________ - a natural, non-living solid with a definite chemical structure.

• Earth’s crust contains more than _________ minerals – only two dozen are common.

• Examples: diamond, quartz, emerald copper• Minerals are made up of ______.• Particles of _______ are arranged in a

particular repeating pattern.

Mineral

4,000 kinds

crystals

crystals

Crystals

• _______ form when minerals are made in nature

• Each type of mineral has its own unique chemical __________.

• Differences in minerals result from the way that particles are arranged.

• Brass – Copper + Zinc –____________because it does not occur naturally

Not a mineral

structure

Mineral

Identifying Minerals

• Minerals are identified by their ____________• _______________ - a scale to measure

hardness of a mineral • The range of the harness scale is from 1

(_______) to 10 (______)• Talc has a harness of __ / diamond is a _____• ________ - refers to how difficult it is to

scratch its surface

characteristics

Moh’s hardness scale

hardness

Softest Hardest

1 10

Other Mineral Characteristics

• _______ - a mineral may have different crystals depending on the kinds of materials that make up its ______.

• The color of a mineral can be seen in its ______.• A mineral can also be identified by the ______

of its crystals.• _______ - minerals show particular patterns

when they are broken along flat planes.

Color

crystals

streak

shape

Cleavage

Luster

• ______ - the appearance of a mineral in reflected light.

• A mineral may appear:– __________– __________– __________– __________– __________

Luster

Metallic

NonmetallicGreasy

Glassy

Waxy

Rocks

• _____ - a solid, natural material made up of one or more minerals

• ___________ - as time passes, rock break down, and the minerals in them are recycled – pattern of change

• The rock cycle takes place over ________ of years.

• There are three types of rocks: __________, __________, and __________

rock

Rock cycle

millions

sedimentaryigneous metamorphic

Sedimentary Rock

• ______________ - made from pieces of rocks and minerals

• Sedimentary rock forms in ________ - the oldest rock at the bottom and the newest rock on top.

• Sedimentary rock is like a “_________” - past events captured in each layer.

• _____ - remains of once living animals or plants

Sedimentary rock

layers

History book

fossils

Sedimentary Rock Continued

• Fossils are ONLY found in _____________• Example of sedimentary rock = ________• Limestone is made from _________________

or from dissolved __________ that settle out of seawater.

Sedimentary rock

limestone

Shells of tiny sea animals

minerals

Igneous Rock

• __________ - forms from magma – molten rock inside of the earth that cools and hardens

• Some igneous rock forms ______________ and is only exposed after rocks above have worn away

• Other igneous rocks form when _____ cools at the Earth’s surface

• When lava cools fast - _______________• When lava cools slowly - _______________

Igneous rock

Below Earth’s surface

lava

Fine-ground rocks form

Coarse-grained rock

Metamorphic Rock

• _____________ - forms when heat, pressure, or chemical reactions change one type of rock into another type of rock.

• Metamorphic rock is made from ___________ or _________.

• Example: ______ is a metamorphic rock made from________ (sedimentary rock)

Metamorphic rock

Sedimentary rockIgneous rock

marblelimestone

Compare and Contrast

• How are the three types of rocks similar and different?

Clues to the Past

• Scientists can tell a great deal about Earth’s history by looking at _____.

• ______________ - scientists look at the layers of sedimentary rock and learn about the relative age of each layer and the minerals found in it.

• Relative dating allows scientists to place past events in ____________

rocks

Relative dating

Sequential order

Rock Cycle