Module 3 – Module 3 – Earth’s CrustEarth’s Crust

Chapter 10 – Minerals, Rocks, Chapter 10 – Minerals, Rocks, and Soiland Soil

CanadaCanada• Canada is known world-wide for its large fields

and impressive landscapes.

• For example, Newfoundland is known as « The Rock ».

• Also, tourists come see the Rocher Percé in Gaspésie. Others come see the Thousand Islands, the Rockies, the Prairies, the mountains in New Brunswick and British Colombia, and the long sandy beaches in Prince Edward Island and Nova Scotia.

Newfoundland a.k.a. “Newfoundland a.k.a. “The Rock”The Rock”

The The RockiesRockies

Mountains in New Brunswick and Mountains in New Brunswick and British ColombiaBritish Colombia

• NB BC

……Thousand IslandsThousand Islands

BeachesBeaches in PEI and NS in PEI and NS

The PrairiesThe Prairies

Reflection QuestionsReflection Questions

• Why are some gemstones valuable while others are worthless?

• Why do plants grow in some places and not in others?

• What is the most valuable gemstone?

Chapter 10 – Key IdeasChapter 10 – Key Ideas

• In this chapter, you will discover:

– How minerals, rocks, and soils form and continue to change in a cycle

– How soil types and crops vary across Canada

– How human activity affects our environment positively and negatively

10.1 – 10.1 – MineralsMinerals

• MineralMineral: is inorganic (lifeless) solid matter that is natural, and composed of one or more elements.

• RockRock: a rock is made up of one or more pure, naturally occurring, non-living solid substances (minerals). A part of the Earth’s Crust is made out of rock.

MineralsMinerals

• Most minerals are quite rare. Only a few (quartz and mica) are common and are found throughout the Earth’s crust.

quartz mica

MineralsMinerals

• A mineral can be an element (a pure substance) or a compound (two or more substances).

• No other mineral has the same set of properties or proportion of elements.

Mineral Formation Mineral Formation Minerals can be formed in 3 ways:

1. Lava and magma cool off and form crystals.

2. A solution evaporates and there are dissolved crystals left in the solution.

3. Existent minerals are sometimes exposed to high temperatures and to strong pressures or are dissolved in a solution; they finish off as new minerals.

JewelryJewelry

• Most jewels are not made up or gold, silver, or platinum. In a natural state these substances are soft and very flexible.

• So they will keep their shape and appear smooth, they must be hardened. They often mix gold, silver and platinum to other metals.

How Hard are Minerals?How Hard are Minerals?

• Which mineral is the hardest?

– The diamond is the substance that is the hardest of all minerals!

• A German scientist called Friedrich MohsFriedrich Mohs created a scale of ten minerals with a « hardness » value of 1 to 10.

The Mohs Hardness ScaleThe Mohs Hardness Scale

• The Mohs Hardness Scale is a useful tool for mineral identification.

• Given that there are over 3000 minerals, other properties are also needed to identify them.

How do we use the scale?How do we use the scale?

• Suppose that you have an unknown mineral that looks like another mineral such as talc. If you scratch it with your fingernail, and it scratches easily, then it could be talc (it is number 1 according to Mohs Scale). If it does not scratch easily, then it is not talc.

• Minerals that are low on Mohs’s scale are softer then those at the bottom of the scale (7 and up).

What to do now…What to do now…

1. In the team shared folder, there is a document “Major Crystal Systems”. Save this document in your folders.

2. Fill out the tables and answer the questions. The website you are to use for the first table is on that document.

3. For the second part (on birthstones) you may use the website of your choice.

Tuesday, May 1Tuesday, May 1stst 2007 2007

1. Finish the document begun yesterday from the Team Shared Folder “Major Crystal Systems”.

2. If you finish before the others, work on your “Famous Scientists” project.

3. We will correct the worksheet today.

Other Clues to Mineral IdentificationOther Clues to Mineral Identification

LUSTRELUSTRE: (shiny): (shiny)Most dull minerals are non-Most dull minerals are non-metals. The “shininess”, or metals. The “shininess”, or lustre, of a mineral depends on lustre, of a mineral depends on how light is reflected from its how light is reflected from its surface.surface.

COLOURCOLOUR::Not all minerals are the same Not all minerals are the same colour all the time. Colour is one colour all the time. Colour is one of the most attractive properties of the most attractive properties

of minerals.of minerals.

STREAKSTREAK::A streak is the colour of the A streak is the colour of the powdered form of the mineral. powdered form of the mineral. Gold leaves a gold streak. Gold leaves a gold streak. Minerals that are too hard will Minerals that are too hard will not leave a streak (7 on Mohs not leave a streak (7 on Mohs

Scale).Scale).

CLEAVAGE and CLEAVAGE and FRACTUREFRACTURE::The way a mineral breaks apart. The way a mineral breaks apart. Cleavage = when it breaks Cleavage = when it breaks along smooth, flat surfaces. along smooth, flat surfaces. Fracture = breaks with rough or Fracture = breaks with rough or jagged edges.jagged edges.

The Six Major Crystal SystemsThe Six Major Crystal Systems

• All of the minerals in Earth’s crust can be grouped according to the 6 different crystal shapes.

1. Cubic / isometric2. tetragonal3. hexagonal4. orthorhombic5. monoclinic6. triclinic

Rock JokesRock Jokes

What does a rock want to be when it grows up?What does a rock want to be when it grows up?

– A Rock Star

What do you do to a baby rock? What do you do to a baby rock?

– Rock it

Where do rocks sleep? Where do rocks sleep?

– BedrockBedrock

Section 10.2 –The cycle of rocksSection 10.2 –The cycle of rocks

There are 3 major rock families (categories):There are 3 major rock families (categories):

1) Igneous rocks

2) Sedimentary rocks

3) Metamorphic rocks

• Each can usually be identified by its appearance.

Igneous RocksIgneous Rocks

• Igneous rocksIgneous rocks: form when hot magma and when hot lava cool and solidify.

• MagmaMagma: is melted rock found below Earth’s crust, where temperatures and pressures are high.

• Any rock that is heated at great depths can melt into magma.

Intrusive vs ExtrusiveIntrusive vs Extrusive• Intrusive rocksIntrusive rocks: are made when magma

cools down and hardens below the Earth’s surface.

• Extrusive rocksExtrusive rocks: are formed when lava cools down on the Earth’s surface.

• (Lava is magma that comes through the cracks of the Earth in the form of a volcanic eruption).

Sedimentary RockSedimentary Rock

• Sedimentary rocksSedimentary rocks: are formed from sediments – loose materials, such as bits of rock, minerals, and plant and animal remains. These sediments become closely packed and cemented together.

• This type of rocks make up about 75% of the rocks we see on the Earth’s surface.

GraniteGranite

• Granite is a rock that is made up of an assortment of minerals.

• Its is often polished and used in buildings and at the base of statues.

• Granite contains these minerals:– feldspar (sparkling grains)– quartz (a glassy crystal)– mica (greenish-grey flakes)– hornblende (dark flecks).

Metamorphic RockMetamorphic Rock

• This type of rock has changed its form from what it was originally. It is formed below the Earth's surface by extreme pressure and heat.

• The “parent rock” will become another type of rock depending on how much pressure and heat is used to change it.

Minerals and Metals at Home!Minerals and Metals at Home!Which minerals are hidden in these Which minerals are hidden in these outdooroutdoor objects: objects:

a) skateboardskateboard: aluminum, calcite, iron, mica, nickel, petroleum products, clays, silica and talc.

g) windowwindow: nepheline syenite and silica.

f) sidewalk (concrete):sidewalk (concrete): gypsum, iron, limestone, clays and silica.

h) roof/shinglesroof/shingles: petroleum products.

k) bricksbricks: : graphite, clays and silica.

Rock JokesRock Jokes

• What is a rock's favorite kind of music? – Rock n’ Roll

• What is a rock's favorite transportation? – A rocket

• What is a rock's favorite cereal?– Cocoa Pebbles

Minerals and Metals at Home!Minerals and Metals at Home!Which minerals are hidden in these Which minerals are hidden in these kitchenkitchen objects: objects:

a) telephonetelephone: copper, gold and petroleum products.

c) fridgefridge: aluminum, copper, iron, nickel, petroleum products and zinc.

e) toastertoaster: copper, iron, nickel, mica, chromium and petroleum products.

i) clockclock: includes iron, nepheline syenite, nickel, petroleum products and silica.

n) dishes/platesdishes/plates: clays.

Minerals and Metals at Home!Minerals and Metals at Home!Which minerals are hidden in these Which minerals are hidden in these officeoffice objects: objects:

a) a) stereo:stereo: gold, iron, nickel and petroleum products.

b) b) cdcd: aluminum and petroleum products.

c) ) chairchair: aluminum and petroleum products.

d)d) deskdesk: copper, iron, nickel and zinc.

f) f) cameracamera: aluminum, iron, gold, nepheline syenite, nickel, petroleum products, silica and silver.

g) g) booksbooks: limestone and clays.

Minerals and Metals at Home!Minerals and Metals at Home!Which minerals are hidden in these Which minerals are hidden in these bathroombathroom objects: objects:

a) a) bathtubbathtub: clays, iron and nickel

e) e) cleaning productcleaning product: silica

g) g) toothpastetoothpaste: fluorite, barite and calcite

i) i) jewelryjewelry: copper, gold, iron, nickel or silver.

k) k) drinking glassdrinking glass:: nepheline syenite and silica

n) n) faucetfaucet:: iron and nickel

Minerals In RocksMinerals In Rocks• The building blocks of rocks are naturally occurring materials,

called minerals. Rocks contain naturally occurring, non-living minerals. Most minerals are rare and can be elements (pure substances) or compounds (combinations of pure substances).

• Minerals are not only found in rocks, but they are also found in your body.– Iron and pyrite help the blood carry oxygen– Kidneys produce crystals, called kidney stones– Calcium and dolomite help regulate water in body cells

- Diamonds are used in surgery, razor blades, computers, dentistry, oil drilling and a glasscutter's wheel has diamonds embedded in it.

The Rock CycleThe Rock Cycle

• So far, we have seen that rocks are constantly changing.

• Rocks continue to change in an ongoing process called the rock cyclerock cycle.

Rock SayingsRock Sayings

• Your head is as hard as a rock.

• I am between a rock and a hard place.

• He is just a chip off the old rock.

• Your head must be full of rocks.

• She has a heart of stone (or heart of gold).

Source: http://library.thinkquest.org/J002289/sayings.html

Test Review for Chapter 10Test Review for Chapter 101.1. The The 3 major rock families3 major rock families & & how they are formedhow they are formed

2.2. The difference between a The difference between a rockrock and a and a mineralmineral

3.3. Mohs’ Hardness Scale Mohs’ Hardness Scale (scale of 1 to 10 and which (scale of 1 to 10 and which mineral is the hardest)mineral is the hardest)

4.4. Intrusive rocksIntrusive rocks vs. vs. Extrusive rocksExtrusive rocks

5.5. MagmaMagma and and LavaLava

Review questionsReview questions

Sciencepower 7:Sciencepower 7:

1.1. p. 310 # 7, 11, 19p. 310 # 7, 11, 19

2.2. p. 288 # 1, 2p. 288 # 1, 2

3.3. p. 299 # 1p. 299 # 1

Review - AnswersReview - Answersp. 310p. 310 #7. #7. A mineral that is A mineral that is cleavedcleaved has smooth, flat surfaces. has smooth, flat surfaces.

A mineral that is A mineral that is fracturedfractured has rough or jagged has rough or jagged edges.edges.

#11. #11. MagmaMagma is melted rock formed under the is melted rock formed under the Earth’s crust.Earth’s crust.

LavaLava is magma that comes through the cracks of the Earth in the form of a volcanic eruption.

#19. #19. DiagramDiagram

Review - AnswersReview - Answersp. 288p. 288

# 1. # 1. RockRock: : a rock is made up of one or more pure, naturally occurring, non-living solid substances (minerals). A part of the Earth’s Crust is made out of rock.

MineralMineral: : is inorganic (lifeless) solid matter that is natural, and composed of one or more elements.

ElementElement: a pure substance: a pure substance

Review - AnswersReview - Answers

P. 288P. 288

#2. #2. LUSTRELUSTRE (shiny), (shiny), CCOLOUROLOUR, , STREAKSTREAK, , CLEAVAGECLEAVAGE andand FRACTUREFRACTURE..

p. 299p. 299

# 1. # 1. One or more mineralsOne or more minerals

10.3 – 10.3 – SoilSoil

• Sediment is an in-between stage in the rock Sediment is an in-between stage in the rock cycle.cycle.

• The slow process of rock formation takes The slow process of rock formation takes thousands of years to occur. thousands of years to occur.

• Rock sediment is commonly called dirt but what Rock sediment is commonly called dirt but what most people call dirt is actually soil.most people call dirt is actually soil.

• SoilSoil: is a mixture of weathered rock, organic : is a mixture of weathered rock, organic matter, mineral fragments, water, and air.matter, mineral fragments, water, and air.

Formation of SoilFormation of Soil

– Earth is covered by a layer of rock and sediment. Earth is covered by a layer of rock and sediment. Sediment and mineral fragments do not become Sediment and mineral fragments do not become soil until plants and animals have lived in them soil until plants and animals have lived in them and added organic matter (leaves, twigs, and and added organic matter (leaves, twigs, and dead worms and insects).dead worms and insects).

– The organic matter creates spaces that can be The organic matter creates spaces that can be filled with air or water. All of these combine to filled with air or water. All of these combine to form soil, a material that can support plants.form soil, a material that can support plants.

Soil ProfilesSoil Profiles

• Soils can take thousands of years to form. Soils can take thousands of years to form.

• The can range in thickness from 60 m in The can range in thickness from 60 m in some areas to just a few centimeters in some areas to just a few centimeters in others. others.

• The layers of soil make up a The layers of soil make up a soil profilesoil profile..

Soil TextureSoil Texture

• TextureTexture: how soil feels when it is rubbed : how soil feels when it is rubbed between your fingers. The particle size between your fingers. The particle size affects how gritty a soil feels.affects how gritty a soil feels.

• Water-holding capacityWater-holding capacity: the soil’s ability : the soil’s ability to hold water. Soil with low water-holding to hold water. Soil with low water-holding capacity tends to be dry most of the time. capacity tends to be dry most of the time.

Chapter 11Chapter 11: Earthquakes, : Earthquakes, Volcanoes, and MountainsVolcanoes, and Mountains

Imagine this…Imagine this…

• Imagine that you are the first person on Imagine that you are the first person on Earth ever to experience an earthquake.Earth ever to experience an earthquake.

• What would you think was happening?What would you think was happening?

• What do you think might be causing it?What do you think might be causing it?

• How would you explain what happened?How would you explain what happened?