Transcript Mountains formed by Stress

Key Terms:
fault block mountain,
upwarped mountain,
folds, folded mountain,
anticline,
syncline
Mountain Building
 Please turn to page 106 in your textbook.
 Stress forces produced by plate movement can
build up mountains on Earth’s surface.

The process occurs over millions of years
 The types of mountains formed from stress forces
are:



Fault Block Mountains
Upwarped Mountains
Folded Mountains
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Mountains formed by Faulting
When movement along faults
moves blocks of rock up or down.
Caused by dip slip faults.
 Uplift occurs over millions of years

Types of mountains formed:


Fault block mountains.
Upwarped mountains.
3
Fault Block Mountains
When normal faults uplift a block
of rock.

Caused by the stress force of tension.
View some images of fault block
mountains at this link.
4
Upwarped Mountains
When reverse or thrust faults uplift
a block of rock.

Caused by the stress force of
compression.
View some images of upwarped
mountains at this link.
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Mountains formed from folding
 Under certain conditions, the stress force built up by
plate movement does not break the rock, but causes
the crust to fold.

Caused by compression.
 Folds


A bend in the rock that forms where part of Earth’s crust is
compressed.
Folds vary in size from a few centimeters across to hundreds of
kilometers wide.
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Types of Folds
 Observe figure 4 on page 107.
 Two types of folds:

Anticline


An upward fold in the rock layers
Syncline

A downward fold in the rock layers.
 View some images of folded mountains
at this link.
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How are mountains formed?
 Open the link below and view the teacher tube video
on How Mountains are Formed.
How are Mountains Formed?
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Mountains formed by Stress: Graphic Organizer
Types of
Mountains
Formed by
Faulting
Folding
Normal
Faults
Caused by
compression
Anticline
Reverse or
Thrust faults
Caused by
Caused by
tension
compression
Form
Syncline Fault Block
Mountains
Form
Upwarped
Mountains
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