Rocks - MR. FETCH · Igneous Rocks Think of minerals as ingredientsThink of ... Mr. Fetch’s Earth Science Classroom Igneous Rocks: Types of Textures ... Microsoft PowerPoint - Lesson

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Mr. Fetch’s Earth Science Classroom

Rocks

What are rocks? What are rocks? What are rocks? What are rocks?

---- Rocks are Rocks are Rocks are Rocks are combinations of mineralscombinations of mineralscombinations of mineralscombinations of minerals stuck together.stuck together.stuck together.stuck together.

---- Minerals (Rice Krispies)Minerals (Rice Krispies)Minerals (Rice Krispies)Minerals (Rice Krispies)

---- Rocks (Rice Krispies Treats)Rocks (Rice Krispies Treats)Rocks (Rice Krispies Treats)Rocks (Rice Krispies Treats)


Igneous Rocks

Think of minerals as ingredientsThink of minerals as ingredientsThink of minerals as ingredientsThink of minerals as ingredients…………

If you have different minerals, you have different rocks. If you have different minerals, you have different rocks. If you have different minerals, you have different rocks. If you have different minerals, you have different rocks.

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Igneous Rocks

There are many different types of rocksThere are many different types of rocksThere are many different types of rocksThere are many different types of rocks…………

All rocks are classified based on how and what they are made of.All rocks are classified based on how and what they are made of.All rocks are classified based on how and what they are made of.All rocks are classified based on how and what they are made of.

---- Like potatoes: mashed, backed, scalloped, etc.Like potatoes: mashed, backed, scalloped, etc.Like potatoes: mashed, backed, scalloped, etc.Like potatoes: mashed, backed, scalloped, etc.

---- Each come from a plain potato, but were made differentlyEach come from a plain potato, but were made differentlyEach come from a plain potato, but were made differentlyEach come from a plain potato, but were made differently


Igneous Rocks

Just like there are different types of potatoes, there are diffeJust like there are different types of potatoes, there are diffeJust like there are different types of potatoes, there are diffeJust like there are different types of potatoes, there are different rent rent rent

types of rockstypes of rockstypes of rockstypes of rocks

The three main types of rocks are:The three main types of rocks are:The three main types of rocks are:The three main types of rocks are:

1. 1. 1. 1. IgneousIgneousIgneousIgneous: made from cooled lava or magma.: made from cooled lava or magma.: made from cooled lava or magma.: made from cooled lava or magma.

2. 2. 2. 2. MetamorphicMetamorphicMetamorphicMetamorphic: rocks change under high heat and pressure.: rocks change under high heat and pressure.: rocks change under high heat and pressure.: rocks change under high heat and pressure.

3. 3. 3. 3. Sedimentary:Sedimentary:Sedimentary:Sedimentary: when sediment is squeezed together. when sediment is squeezed together. when sediment is squeezed together. when sediment is squeezed together.

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Igneous Rocks

Igneous rocks form when magma or lava Igneous rocks form when magma or lava Igneous rocks form when magma or lava Igneous rocks form when magma or lava coolscoolscoolscools and hardens.and hardens.and hardens.and hardens.

---- Magma: Magma: Magma: Magma: insideinsideinsideinside EarthEarthEarthEarth

---- Lava: Lava: Lava: Lava: outsideoutsideoutsideoutside EarthEarthEarthEarth

Igneous rocks are Igneous rocks are Igneous rocks are Igneous rocks are classifiedclassifiedclassifiedclassified according to:according to:according to:according to:

---- WhereWhereWhereWhere they are made.they are made.they are made.they are made.

---- The The The The texture texture texture texture of the rock.of the rock.of the rock.of the rock.

---- What they are What they are What they are What they are made ofmade ofmade ofmade of....


Igneous Rocks: Where they are made?

Igneous rocks can form inside Earth or outside Earth.Igneous rocks can form inside Earth or outside Earth.Igneous rocks can form inside Earth or outside Earth.Igneous rocks can form inside Earth or outside Earth.

Inside Inside Inside Inside Earth: Earth: Earth: Earth: INTRUSIVE IGNEOUS ROCKSINTRUSIVE IGNEOUS ROCKSINTRUSIVE IGNEOUS ROCKSINTRUSIVE IGNEOUS ROCKS

---- ““““InInInIn”””” side earth.side earth.side earth.side earth.

---- Think about the Think about the Think about the Think about the ““““interiorinteriorinteriorinterior”””” of your car.of your car.of your car.of your car.

---- Think about an Think about an Think about an Think about an ““““interiorinteriorinteriorinterior”””” designer.designer.designer.designer.

---- What cools? Magma or Lava?What cools? Magma or Lava?What cools? Magma or Lava?What cools? Magma or Lava?

Outside Earth: Outside Earth: Outside Earth: Outside Earth: EXTRUSIVE IGNEOUS ROCKSEXTRUSIVE IGNEOUS ROCKSEXTRUSIVE IGNEOUS ROCKSEXTRUSIVE IGNEOUS ROCKS

---- ““““ExExExEx”””” it something means to go it something means to go it something means to go it something means to go ““““outoutoutout”””” of it.of it.of it.of it.

---- Think about the Think about the Think about the Think about the ““““exteriorexteriorexteriorexterior”””” of your house.of your house.of your house.of your house.

---- What cools? Magma or LavaWhat cools? Magma or LavaWhat cools? Magma or LavaWhat cools? Magma or Lava

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Igneous Rocks: Where they are made?


Igneous Rocks: Texture of the Rocks?

Igneous rocks have different Igneous rocks have different Igneous rocks have different Igneous rocks have different texturestexturestexturestextures....

---- Texture is how a rock Texture is how a rock Texture is how a rock Texture is how a rock looks and feelslooks and feelslooks and feelslooks and feels....

---- Texture is based on the Texture is based on the Texture is based on the Texture is based on the sizesizesizesize of of of of crystalcrystalcrystalcrystal grains in the rock.grains in the rock.grains in the rock.grains in the rock.

---- Sometimes they are large, sometimes small.Sometimes they are large, sometimes small.Sometimes they are large, sometimes small.Sometimes they are large, sometimes small.

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Igneous Rocks: Types of Textures

Pegmatite:

Very large crystal grains

They are so big that some even join together to become bigger

You can see them with your eyes

Ex: Pegmatite

Coarse-grained:

Large crystal grains

You can see them with your eyes

Ex: Granite

Fine-grained:

Small crystal grains

Too small to be seen with your eyes – you need a microscope

Ex: Basalt

Glassy/Volcanic Glass:

No crystals at all

Ex: Obsidian or Pumice

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Igneous Rocks: Types of Textures �� Rate of Cooling

Porphyry:Porphyry:Porphyry:Porphyry:

PorphyryPorphyryPorphyryPorphyry is when you have a mix of is when you have a mix of is when you have a mix of is when you have a mix of large and small crystallarge and small crystallarge and small crystallarge and small crystal grains.grains.grains.grains.

Think of the word potpourriThink of the word potpourriThink of the word potpourriThink of the word potpourri…………thatthatthatthat’’’’s a collection of things. (s a collection of things. (s a collection of things. (s a collection of things. (

big and small crystals) big and small crystals) big and small crystals) big and small crystals)

What could have caused this?What could have caused this?What could have caused this?What could have caused this?

How do we get big crystals? How do we get big crystals? How do we get big crystals? How do we get big crystals? ––––slow cooling inside Earthslow cooling inside Earthslow cooling inside Earthslow cooling inside Earth

How do we get small crystals? How do we get small crystals? How do we get small crystals? How do we get small crystals? –––– quick cooling outside Earthquick cooling outside Earthquick cooling outside Earthquick cooling outside Earth

This rock experienced two cooling situations.This rock experienced two cooling situations.This rock experienced two cooling situations.This rock experienced two cooling situations.



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Pegmatite and coarsePegmatite and coarsePegmatite and coarsePegmatite and coarse----grained textures have very grained textures have very grained textures have very grained textures have very large large large large crystals.crystals.crystals.crystals.

---- The The The The slowerslowerslowerslower the magma cools, the larger the mineral crystals.the magma cools, the larger the mineral crystals.the magma cools, the larger the mineral crystals.the magma cools, the larger the mineral crystals.

---- Rocks that cool slowly have larger crystalsRocks that cool slowly have larger crystalsRocks that cool slowly have larger crystalsRocks that cool slowly have larger crystals....

SLOW COOLING = SLOW COOLING = SLOW COOLING = SLOW COOLING = LARGE CRYSTALSLARGE CRYSTALSLARGE CRYSTALSLARGE CRYSTALS

Ex: Let’s say you are trying to cool a cake you made. Instead

of putting it outside to cool, you turn the oven off and keep it

in there to cool. You won’t be able to eat the cake for awhile

because it will take longer to cool since it is in the hot oven.

Ex: Say you are a farmer. You plant your crops in spring

and let them grow for many months until fall. The crops

will be big because they had lots of time to grow before

the ground froze.



Fine grained texture means that there are very Fine grained texture means that there are very Fine grained texture means that there are very Fine grained texture means that there are very tinytinytinytiny crystal grains.crystal grains.crystal grains.crystal grains.

---- The faster the magma cools, the smaller the mineral crystals.The faster the magma cools, the smaller the mineral crystals.The faster the magma cools, the smaller the mineral crystals.The faster the magma cools, the smaller the mineral crystals.

---- Rocks that cool fast have small crystals.Rocks that cool fast have small crystals.Rocks that cool fast have small crystals.Rocks that cool fast have small crystals.

FAST COOLING = FAST COOLING = FAST COOLING = FAST COOLING = SMALL CRYSTALSSMALL CRYSTALSSMALL CRYSTALSSMALL CRYSTALS

Ex: Back to the cake, let’s say you put it in the fridge to

cool. It will certainly cool faster because of the cooler

temperatures.

Ex: Back to the crops. Instead of letting the crops grow

all summer, you harvest them early. They won’t get to

grow as big because they didn’t have enough time.

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SUMMARY:SUMMARY:SUMMARY:SUMMARY:

Intrusive Rocks:Intrusive Rocks:Intrusive Rocks:Intrusive Rocks:

Form Form Form Form insideinsideinsideinside the Earth where it is hot, so the magma the Earth where it is hot, so the magma the Earth where it is hot, so the magma the Earth where it is hot, so the magma cools slowlycools slowlycools slowlycools slowly

producing large crystals. producing large crystals. producing large crystals. producing large crystals.

Extrusive Rocks:Extrusive Rocks:Extrusive Rocks:Extrusive Rocks:

Form Form Form Form outsideoutsideoutsideoutside of the Earth where it is cool, so the lava of the Earth where it is cool, so the lava of the Earth where it is cool, so the lava of the Earth where it is cool, so the lava cools quicklycools quicklycools quicklycools quickly

producing small or no crystals. producing small or no crystals. producing small or no crystals. producing small or no crystals.

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Igneous Rocks: Magma Types

GraniticGraniticGraniticGranitic

---- Lots of Lots of Lots of Lots of silicasilicasilicasilica, low Fe, low Fe, low Fe, low Fe

----Therefore it will be Therefore it will be Therefore it will be Therefore it will be light in colorlight in colorlight in colorlight in color....

AndesiticAndesiticAndesiticAndesitic

----Medium amounts of Medium amounts of Medium amounts of Medium amounts of SiSiSiSi/Fe/Fe/Fe/Fe

---- Not light, but not darkNot light, but not darkNot light, but not darkNot light, but not dark

Basaltic Basaltic Basaltic Basaltic

---- Lots of FeLots of FeLots of FeLots of Fe, low Si, low Si, low Si, low Si

---- Very darkVery darkVery darkVery dark in colorin colorin colorin color

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Igneous Rocks: Magma Types

LetLetLetLet’’’’s say you make batter.s say you make batter.s say you make batter.s say you make batter.

You take that batter and pour it in a pan and you make round, flYou take that batter and pour it in a pan and you make round, flYou take that batter and pour it in a pan and you make round, flYou take that batter and pour it in a pan and you make round, flat pancakes.at pancakes.at pancakes.at pancakes.

You take that batter and pour it into a waffle iron and make thiYou take that batter and pour it into a waffle iron and make thiYou take that batter and pour it into a waffle iron and make thiYou take that batter and pour it into a waffle iron and make thick waffles.ck waffles.ck waffles.ck waffles.

The same batter makes two completely different items based on thThe same batter makes two completely different items based on thThe same batter makes two completely different items based on thThe same batter makes two completely different items based on the way it was made.e way it was made.e way it was made.e way it was made.

This is just like magma This is just like magma This is just like magma This is just like magma –––– when magma cools fast, you get one type of rock.when magma cools fast, you get one type of rock.when magma cools fast, you get one type of rock.when magma cools fast, you get one type of rock.

When it cools slow, you get a completely different type of rock.When it cools slow, you get a completely different type of rock.When it cools slow, you get a completely different type of rock.When it cools slow, you get a completely different type of rock.

Ex: Granitic magma forms granite and rhyolite when it cools diffEx: Granitic magma forms granite and rhyolite when it cools diffEx: Granitic magma forms granite and rhyolite when it cools diffEx: Granitic magma forms granite and rhyolite when it cools differently. erently. erently. erently.

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Rocks - MR. FETCH · Igneous Rocks Think of minerals as ingredientsThink of ... Mr. Fetch’s Earth Science Classroom Igneous Rocks: Types of Textures ... Microsoft PowerPoint - Lesson