Transcript INSTRUSIVE igneous rocks

Introduction to Igneous Rocks
Audience: 9-12th Grade Earth Science Class
•The purpose of this tutorial is to serve as a review of presented
concepts involving igneous rocks and igneous rock terms.
•Objectives:
•Describe the processes that form the different kinds of igneous rocks.
•Explain how crystal sizes of igneous rocks indicates the rate of
cooling.
•Explain how crystal size can also determine whether a rock is intrusive
or extrusive.
Look for the arrow
buttons to move you
forward or backward
in this tutorial
Created by: Kelly L. Taunt
All igneous rocks begin as magma
As with other rocks, igneous rocks are classified by their
mineral composition and texture.
Igneous Rock Color
Felsic: Light colored, formed from magma with a large amount of silica.
Intermediate: Not too dark or too light
Mafic: Dark colored, formed from magma with a lot of iron and magnesium.
Which building do you think took longer
to build?
Skyscraper?
Playhouse?
So as with the buildings on the previous slide, a large building will take longer
to build. Igneous rocks that have a long time to cool will have:
LARGE crystals
A small playhouse may be built in a small amount of time. So igneous
rocks that cool quickly will have:
small
crystals
Practice Quiz ( 2 Slides total): Click the correct answer with your mouse to see if you are
correct.
Cooled Quickly Try again!
Cooled Slowly
YES!
Cooled Quickly
Cooled Slowly
Correct!
Try Again
Which person/people will stay warmer longer?
Her?
Them?
Just like the couple inside next to the fireplace
(inside the house), rocks that are IN the Earth stay
warmer longer. Igneous rocks that form IN the
Earth are called INSTRUSIVE igneous rocks.
Inside the Earth.
Just like the girl outside, rocks that are OUTSIDE (exiting the
Earth) cool quickly. Igneous rocks that are formed outside of the
earth’s surface are EXTRUSIVE igneous rocks.
On the Earth’s
surface, outside
of the Earth.
Since rocks that cool on the outside of the Earth cool faster, extrusive igneous
rocks usually have:
small
crystals
Rocks that are on the inside of the Earth take longer to cool because they
are near a heat source, therefore, intrusive rocks usually have:
LARGE crystals
Can you if this rock is intrusive or extrusive based on crystal size?
Intrusive
Try Again
Extrusive
Correct!
Can you if this rock is intrusive or extrusive based on crystal size?
Intrusive
Correct!
Extrusive
Try Again
Can you if this rock is intrusive or extrusive based on crystal size?
Intrusive
Correct!
Extrusive
Try Again
Are you ready for a quiz?
No, I need to review types of magma.
No, I need to review crystal size.
No, I need to review intrusive and extrusive rocks.
Yes, Let’s Go! Click here.
An igneous rocks that forms on the outside of
Earth’s crust would be classified as a(n)
________.
A. extrusive
B. felsic
C. intrusive
A mafic igneous rock would be:
A. Light colored
B. Dark colored
C. Intermediate
A rock that has small crystals probably formed
in which location?
A. Outside of a volcano
B. Deep inside a volcano
C. Under the Earth’s crust
The rock below would be classified
as a(n): ________________
A. Mafic
B. Felsic
C. Intermediate
The rocks below probably formed
____________, and have __________ crystals.
A. Slowly, Large
B. Slowly, Small
C. Quickly, Small
When an igneous rock has large crystals, it
probably formed ____________.
A. Quickly
B. Intermediate
C. Slowly
Intrusive igneous rocks have _______ crystals.
A. Small
B. Large
C. Intermediate
Rocks that form outside of the earth are called
what?
A. Intrusive
B. Extrusive
C. Exterior
All igneous rocks originally start as _______.
A. Other rocks
B. Magma
C. Sediments
The rock below represents what type of
igneous rock?
A. Felsic, Intrusive
B. Mafic, Intrusive
C. Felsic, Extrusive
GREAT!
Try one more time?