I) Where Mountains FormA)Mountain Belts

1) Most Mountains are associated with convergent plate boundaries

2) Most mountains occur in long belts that follow convergent boundaries

3) Himalayas lie along a current convergent boundary

4) Appalachians are in the middle of a plate – but were formed by converging plates over a billion years ago.

B) Continental Margins (land and sea meet)

1) Active Margins

a) occur along plate boundaries

b) mountain building takes place

c) Himalayan Mountains2) Passive Margins

a) stable areas away from plate

boundaries

b) Appalachian Mountains

c) Passive margins provide the materials or

sediments from which mountains form.

Active

Passive

IV) Mountain Building

A)Major mountain systems are related

to plate tectonics. Most mountains

form along convergent boundaries

Where else would

you find mountains?Divergent Boundaries

Hot Spots

V) Mountain Facts

A) Himalayan Mountains

1) The largest/highest mountain range

B) Mid-Atlantic Ridge

1) The longest mountain range

Factors that affect mountain Factors that affect mountain DeformationDeformation

• Deformation – all changes that occur to a body of rock.

1. Temperature2. Pressure3. Rock Type4. Time exposed to pressure or heat

Tectonic ForcesTectonic Forces

Mountains are the result of rock that is permanently deformed by stress/forces

• Three types of forces cause three types of faults:

• Tension• Compression• Shear

1) Break in crustal rock with movement

Normal FaultsNormal Faults((Dip-slip fault)Dip-slip fault)

Normal Reverse Thrust Strike-Slip

Type of Force

Name of Boundary

Type of Mountains

Direction it is moving /illustration

Reverse FaultsReverse Faults ( (Dip-slip fault)Dip-slip fault)

• Caused by COMPRESSION forces• Occur along convergent plate boundaries• Hanging wall surface moves UPWARD

Strike-Slip FaultsStrike-Slip Faults

• Caused by SHEAR forces• Occur along transform plate boundaries• Rocks on either side of fault line move

past each other with NO vertical movement.

http://www.youtube.com/watch?v=BLZurdq2qpk&feature=related

Horsts & Grabens

• Large blocks of crust that rise due faulting on either side of the block.

•http://www.youtube.com/watch?v=5rmF4bY7VMk&feature=related

Name this fault! Name this fault!

III) Types of Mountains

A)Mountains are classified according

to their dominant featuresB) Four main categories

1) Volcanic mountains

Volcanic MountainsVolcanic Mountains• Formed by lava and pyroclastic material that

build up.

2) Folded mountainsa) Largest mountains on Earthb) Urals, Himalayas, Appalachians

Folded MountainsFolded Mountains

• Mountains that form from folding processes (compression)

A) Folds

1) Rock is bent into a series of waves2) Results from compressional force3) Two common types of folds

a) Anticline – upward fold of rockb) Syncline – downward fold of rock

AnticlineAnticline

SynclinesSynclines

SynclineSyncline

MonoclineMonocline

Subduction zone animationSubduction zone animation

• http://www.youtube.com/watch?feature=endscreen&NR=1&v=K8J7t3KYr9c

3) Fault-block mountains a) Uplifted

b) Sierra Nevada Mountains

Fault-block mountains

a) Tilted

b) Teton Range, WY

4) Dome Mountains

a) Individual, isolated structures that form in layers of sedimentary rock.

b) There are two types of dome mountains:

Plutonic Dome

• an igneous intrusion

pushes up existing rock

layers.

Tectonic Dome

Tectonic Dome:

Black Hills of South Dakota (Mt. Rushmore)

Yosemite National Park

• uplifting forces arch

rock layers into a

dome

Normal Reverse Thrust Strike-Slip

Type of Force

Name of Boundary

Type of Mountains

Direction it is moving /illustration