Name: _______________________________
Date: ______________________________
Chapter 11: Deformation of the Crust
Section 2: How Mountains Form
Mountain Ranges and Systems
•
Many mountains form due to extreme _________________________________.
•
Mountain range - a series of mountains that are closely related in orientation, ______________,
and mode of formation.
•
A group of mountain ranges that are adjacent is called a ________________________________.
•
The largest mountain systems are part of two larger systems called
_______________________________________________.
•
Earth’s two major mountain __________________ are the circum-Pacific belt and the EurasianMelanesian belt.
Plate Tectonics and Mountains
•
The circum-Pacific and the Eurasian-Melanesian Mountain belts are both located along
________________________________________plate boundaries.
•
The location of these two mountain belts provides evidence that most mountains form as a
result of __________________________________ between tectonic plates.
•
Sometimes mountains, such as the __________________________________, do not lie along
active convergent plate boundaries. However, evidence indicates that the places at which these
ranges formed were _____________________________________________________________.
Collisions between Continental and Oceanic Crust
•
Some mountains form when
oceanic lithosphere
____________________________
beneath the continental
lithosphere at convergent plate
boundaries. This type of collision
produces such
_________________________________
__________________________________________________________that high mountains
are uplifted.
•
In addition, the subduction of the oceanic lithosphere causes partial _______________________
of the overlying mantle and crust.
Name: _______________________________
•
Date: ______________________________
This melting produces magma that may eventually erupt to form
_____________________________________________________________ on Earth’s surface.
Collisions Between Oceanic Crust and Oceanic Crust
•
_________________________
commonly
form where two plates whose
edges consist of oceanic
lithosphere collide.
•
As the ____________________
oceanic plate subducts beneath
the other oceanic plate, fluids from
the subducting lithosphere cause
partial melting of the overlying mantle and crust.
•
The resulting magma rises and breaks through the oceanic lithosphere. These eruptions of
magma form an arc of volcanic mountains on the __________________________________.
Collisions Between Continents
•
Mountains can form when
__________ continents collide.
•
An example of this type of
collision is the formation of
the ___________________
_______________________ in
which the oceanic
lithosphere of the Indian
plate subducted beneath the
Eurasian plate.
•
When the continental lithosphere of both plates collided, _____________________ stopped,
but the collision continued. The intense deformation that resulted from the collision uplifted the
Himalayas. Because the plates are still colliding, the Himalayas are still
_______________________________________.
•
Why are the Himalayas growing taller today?
Name: _______________________________
Date: ______________________________
Types of Mountains
•
Scientists ____________________________mountains according to the way in which the crust
was deformed and shaped by mountain-building stresses.
Folded Mountains and Plateaus
•
Many of the highest mountain ranges in the world consist of folded mountains that form when
continents ________________________.
•
Folded mountain - a mountain that forms when rock layers are ______________________
together and uplifted.
•
The same stresses that form folded mountains also uplift plateaus, which are large, __________
areas of rock ____________ above sea level.
•
Most plateaus form when _________________, _______________________ layers of rock are
______________________ uplifted so that the layers remain flat instead of faulting and folding.
•
Most plateaus are located near ________________________________________________.
•
Plateaus can also form when layers of ___________________________ harden and pile up on
Earth’s surface or when large areas of rock are _______________________________.
Fault-Block Mountains and Grabens
•
Where parts of Earth’s crust have been ________________________ and broken into large
blocks, faulting may cause the blocks to tilt and drop relative to other blocks.
•
Fault-block mountain - a mountain that forms where faults break Earth’s crust into large blocks
and some blocks _______________________________ relative to other blocks.
•
The same type of faulting that forms fault-block mountains also forms ____________________,
____________________________ valleys called grabens.
•
______________________________ develop when steep faults break the crust into blocks and
one block slips downward relative to the surrounding blocks.
•
Grabens and fault-block mountains commonly occur ________________________________.
Dome Mountains
•
A dome mountain is a less common type of mountain that forms when _______________ rises
through the crust and __________________________the rock layers above the magma.
•
Dome mountain - a circular or _____________________, almost symmetrical elevation or
structure in which the stratified rock slopes downward gently from the
_______________________________________ of folding.
•
Dome mountains may also form when tectonic forces ____________________ uplift rock layers.
•
Name three types of mountains found in the United States.
Name: _______________________________
Date: ______________________________
Volcanic Mountains
•
Mountains that form when magma _________________ onto Earth’s surface are called volcanic
mountains, which commonly form along ______________________________ plate boundaries.
•
Some of the largest volcanic mountains are part of the _______________________ ridges along
_______________________________ plate boundaries.
•
Other large volcanic mountains form on the ocean floor at ___________________________,
which are volcanically active areas that seem to correspond to places where hot material rises
through Earth’s interior and reaches the __________________________________.
The diagrams below shows the types of mountains found in the United States.
Death Valley is a graben that lies
between two mountain chains and has the
lowest elevation in the United States.
The Sierra Nevada Range in California
contains many fault-block mountains.
The Colorado Plateau is near the Rockies.
This dome mountain is part of
the Hudson Highlands in NY.
The Appalachian Mountains stretch from Georgia to
Canada and contain many older, eroded mountains.