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Flashcards in Mass Movements Deck (13)
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1
Q

Gravity’s 2 components

A

Surface parallel component “D”: parallel to gravity’s force.

Surface Perpendicular Component “N”: produces friction “F” which resists downward force of “D”

If F>D then the object is stable

2
Q

Creep

A

is the gravitational process of things being pulled downward.

3
Q

Angle of repose

A

is the angle to which you can stack something before it becomes unstable.

4
Q

The formula for energy is=

A

PE=MGH

5
Q

External and Internal causes of mass movement

A

External: increase of mass on slope, the steeping of the slope and removal of support

Internal: is weathering and the adverse of geological structure.

6
Q

External and internal role of water

A

External: rainfall increases erosion, water-based undercutting of slopes occurs.

Internal: additional weight is added, decreased cohesion through an increase in pore water pressure. The dissolution of the material.

7
Q

3 Types of movement

A

fall, slide, and flow

8
Q

Plot mudflow, earthflow, landslide, slump, rockfall in terms of speed and moisture

A
MUDFLOW = WET AND FAST
EARTH FLOW= WET AND SLOWER
LANDSLIDE= MEDIUM AND FAST
SLUMP= MEDIUM AND SLOW
ROCKFALL= DRY AND FAST
9
Q

Mitigation for mass movement focuses on?

A

reshaping the topography by:
focusing on reducing gravity and loose material
increasing cohesion and the shear strength (resistance)
controlling water content and erosion through warning systems
diversion and containment through barriers

10
Q

Shear force, shear strength, normal force

A

the normal force is equal to the gravity pulling it down
the shear strength is looking to resist
the shear force wants to follow the direction of gravity on the slope.

11
Q

Slope is the product of what features

A

Uplift + Erosion

12
Q

what besides gravity causes creep

A

freeze and thaw

13
Q

what causes slump

A

excess water in thick unconsolidated deposits