LEQ How do stress forces in Earths crust

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LEQ: How do stress forces in Earth’s crust form mountains and what kinds of

LEQ: How do stress forces in Earth’s crust form mountains and what kinds of mountains are formed from the 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

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 2

Mountains formed by Faulting When movement along faults moves blocks of rock up or

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

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

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. 5

Mountains formed from folding Under certain conditions, the stress force built up by plate

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. 6

Types of Folds Observe figure 4 on page 107. Two types of folds: Anticline

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. 7

How are mountains formed? Open the link below and view the teacher tube video

How are mountains formed? Open the link below and view the teacher tube video on How Mountains are Formed. How are Mountains Formed? 8

Mountains formed by Stress: Graphic Organizer Types of Mountains Formed by Folding Faulting Normal

Mountains formed by Stress: Graphic Organizer Types of Mountains Formed by Folding Faulting Normal Faults Caused by compression Caused by Anticline tension Form Syncline Fault Block Mountains Reverse or Thrust faults Caused by compression Form Upwarped Mountains 9