Download Chapter 11 Mountain Building

Chapter 11 Mountain Building:
Section 11.1 Forces in Earth’s Crust:
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Earth has 14 ___________________ over 8000 meters (~14,250 ft.)
Deformation of Rock:
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________________________ – any change in the original shape and/or size of a rock body. Every
rock, no matter how strong, has a point which it will bend or break.
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Most deformation occurs at _________________________ where rocks are subjected to stress and
strain.
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_______________________ – the force per unit area acting on a solid. Rocks begin to fold, flow, or
fracture when subjected to stress greater than their own strength.
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_______________________ – the change in shape or volume or a rock due to stress.
Types of Stress:
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________________________
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________________________
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________________________
Principle of Isostasy:
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__________________________ – concept of floating crust in gravitational balance.
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__________________________ – the process of establishing a new level of gravitational balance.
Newly formed mountains sink deep into the crust due to their ______________________________.
As mountains weather and erode away they become lighter, and the crust rises in response. This is an
example of an ________________________________.
Section 11.2 Folds, Faults, and Mountains:
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During mountain building, __________________________________________ often bend flat-lying
sedimentary and volcanic rocks into wavelike ripples called folds.
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There are three types of folds –
1. ____________________
2. ____________________
3. ____________________
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The Appalachian and Himalayan Mountains are ______________________________.
Types of Folds:
1._________________________ -- Upward fold of rock – an arch
2._________________________ -- Downward fold in rock – a trough
3._________________________ -- Step-like Fold
Types of Faults:
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_______________________– rock surface immediately above the fault.
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_______________________ – the rock surface below the fault.
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The major types of faults are normal faults, reverse faults, thrust faults, and strike-slip faults.
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_______________________– occur due to tensional stress. The hanging wall block moves down
relative to the footwall. Found at divergent boundaries. Angles are often 60 0
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_______________________ – result from compressional stress. The hanging wall block moves up
relative to the footwall. High angle faults > 450. Convergent boundary
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_______________________– reverse faults with angles less than 450. The hanging wall goes up an
over the footwall. Convergent boundary
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_______________________– produced by shearing stress at transform boundaries. The movement
is horizontal and parallel to the trend, or strike, of the fault.
Types of Mountains:
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The major types of mountains include volcanic mountains, folded mountains, fault-block mountains,
and dome mountains.
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____________________________ – processes involved in mountain building.
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____________________________ – several mountains of similar shape, age, and structure. The
Clinch Mountain Range is in this area.
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____________________________ – group of mountain ranges in the same region. We live in the
Appalachian system.
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____________________________ – caused by compressional forces found at convergent boundaries
that fold rock at reverse and thrust faults. The Appalachian Mountains, the Himalayan Mountains,
and the Alps are some examples of folded mountains.
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____________________________ – vents in the Earth’s crust that allow magma to come to the
surface.
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_____________________________ – form as large blocks of crust are uplifted and tilted along
normal faults.
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_____________________________ – block of crust that drops down due to normal faulting. It
creates the valley floor.
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_____________________________ – blocks of crust that border the graben that stay uplifted
creating the mountains.
Landforms:
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Up-and-down movements of the crust can produce a variety of landforms, including plateaus,
domes, and basins.
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_____________________________ – broad, flat area of land uplifted to a relatively high elevation.
The Colorado Plateau is cut by the Grand Canyon.
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_____________________________ – broad upwarped areas of land caused by laccoliths. The Black
Hills of South Dakota are an example.
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_____________________________ – downwarped structures in the crust caused by plate motions
causing the crust to bend downward.
Section 11.3 Mountains and Plates Convergent Boundary Mountains:
Convergent Boundary Mountains:
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____________________________________________ – when two oceanic plates collide, one will
subduct beneath the other resulting in a deep ocean trench and a volcanic island arc. An example is
the Aleutian Islands of Alaska.
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_____________________________________________ – when they converge it can produce inland
volcanic mountains along with some folded mountains.
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Examples include the Cascade Range, the Andes of South America, and the Coastal Range on the
West Coast of the United States.
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_____________________________________________ – when two continental plates collide folded
mountains are formed. Examples include the Appalachians and the Himalayas.
Divergent Boundary Mountains:
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Most mountains are formed at convergent boundaries, but some are formed at divergent
boundaries along the mid-ocean ridges. They are _____________________________________ made
of volcanic rock.
Non-Boundary Mountains:
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Some mountains do not form at plate boundaries. These are _____________________________ that
form at a hot spot, a weak area in the Earth’s crust. Fault-block mountains and upwarped(domed)
mountains can also form a long way from plate boundaries
Continental Accretion:
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________________________________ – this process enlarges continental landmasses and forms
mountains along the edges of continents. Pieces of crust that collide with the continent become
stuck or embedded in the continental crust.
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________________________________ – accreted crustal blocks.