Exam 3 part 1

Question 1

What causes mass wasting?

Answer 1

Gravity

Question 2

When some one talks about mass wasting what are they usually referring to?

Answer 2

They refer to:

1) the downslope movement of rock
2) regolith and soil under direct influence of gravity

Question 3

What are the 2 combined effects that produce stream valleys?

Answer 3

1. Mass wasting

2. Running water

Question 4

What is regolith?

Answer 4

Broken up rocks

Question 5

What is the minimum angle required for mass wasting?

Answer 5

There is not minimum angle required

Question 6

What kind of area can cause spectacular and rapid mass wasting?

Answer 6

Areas of rugged, geologically young mountains.

Question 7

What slowly lowers the land surface and what keeps all land from being sea level?

Answer 7

Mass wasting lowers the land surface but plate tectonics/mountains building keep all land from being sea level

Question 8

Ultimately where does mass wasting materials end up?

Answer 8

The ocean.

Question 9

What can affect the gravity of a rock on a slope so that it falls downwards?

Answer 9

Shear stress

Question 10

What is the opposite of shear stress?

Answer 10

Friction

Question 11

Does gravity change at all?

Answer 11

No, gravity is a concept that does not change.

Question 12

What makes a rock stable on a slope?

Answer 12

When the friction is greater than the shear stress

Question 13

What are the two things that cause landslide to happen?

Answer 13

1) Controlling factors

2) Triggers

Question 14

What are two controlling factors of landslides?

Answer 14

1) Water (Decreases friction/adds weight)

2) Oversteeping slopes

Question 15

What are 3 things that could trigger a landslide?

Answer 15

1) Water (Rain/shear stress increase)
2) Earth Quakes (Cause extensive damage/liquidfaction
3) Removal of anchoring vegetation

Question 16

What could cause a landslide (No triggers)?

Answer 16

Slope materials could weaken overtime and increase shear stress

Question 17

What are the two things that classify a landslide event?

Answer 17

1) Types of material involved

2) Type of motion

Question 18

What are the 3 types of materials involved with a landslide?

Answer 18

1) Mud (Clays and silts)
2) Earth (Regolith)
3) Rock

Question 19

What are the 3 types of motion involved with an landslide?

Answer 19

1) fall (free falling pieces)
2) Slide (Material moves along a surface as a mass)
3) flow (Material moves as a chaotic mixture)

Question 20

What is a talus slope?

Answer 20

Debris that piles up to a characteristic angle (Looks lose, like sand)

Question 21

What are the 7 different forms of mass wasting?

Answer 21

1) Slump
2) Rock Slide
3) Debris Flow
4) Earth Flow
5) Creep
6) Solifluction
7) Submarine landslides

Question 22

what is a slump?

Answer 22

Movement of mass of rock or loose material as a unit along a curved surface

Question 23

What is a rock slide?

Answer 23

Blocks of bedrock slide down a slope. Generally fast and destructive.

Question 24

Describe what a debris flow is?

Answer 24

It’s a lahar, mostly soil, regolith, water. Usually in channels in dry areas

Question 25

What is an Earth flow?

Answer 25

This is a flow of soil that is clay or silt, it is saturated by water and is formed on hillsides in humid regions, usually next to highways

Question 26

What is a creep?

Answer 26

Slow moving soil and regolith, caused by the expansion and contraction of material (Ice formation). Can be seen by bent tree stumps

Question 27

What is solifluction?

Answer 27

This is a gentle slope of mass wasting, usually areas that were under permafrost thaw out and they slide downhill because they are ontop of impermeable clay

Question 28

What are submarine landslides?

Answer 28

They are little landslides that occur on the flank of seamounts which are underwater volcanoes. When the slide occurs, water replaces it causing tsunamis.

Question 29

What are two slow moving mass wasting?

Answer 29

1) Creep | 2) Solification

Question 30

What is the hydrolic cycle?

Answer 30

The hydrolic cycle is a summary of the circulation of earth's water supply.

Question 31

What are the six parts to the hydrolic cycle?

Answer 31

1) Precipitation 2) Evaporation 3) Infiltration 4) Run off 5) Transpiration 6) Evaportranspiration

Question 32

What's the first part to the hydrolic cycle?

Answer 32

Evaporation

Question 33

What powers evaporation and where does it usually occur?

Answer 33

Solar energy and usually occurs from the ocean

Question 34

Where do the salts in the ocean come from?

Answer 34

Chemical weathering from land

Question 35

What kind of hazard are sinkholes?

Answer 35

A ground water hazard

Question 36

What purifies water and makes it fresh?

Answer 36

Evaporation

Question 37

Where do oceans get their chemistry from?

Answer 37

From land streams that take both solids and particles to the ocean

Question 38

How are streams still moving even without rain?

Answer 38

ground water

Question 39

What is a sheetflow?

Answer 39

This is running water without being confined to a canal

Question 40

What are rills?

Answer 40

They are tiny channels of water that are caused by sheet flow

Question 41

What are the 5 things that will control infiltration capacity?

Answer 41

1) Intensity and duration of rainfall 2) Prior wetted condition of the soil 3) Soil texture 4) Slope of the land 5) Nature of the vegetation cover

Question 42

What is the perfect soil?

Answer 42

One that has both air and space, both porous and permeable

Question 43

What is porosity and what is permeability?

Answer 43

Porosity is the amount of space you have and permeability how well those spaces are connected

Question 44

In the terms of porosity and permeability, where does clay stand?

Answer 44

Clay is porous but not permeable

Question 45

Why does water cling?

Answer 45

Because of electrical charges

Question 46

Is the dormant season a better time for infiltration?

Answer 46

Yes.

Question 47

If you see rills in the soil, what does that tell you about the soil?

Answer 47

It tells me that the soil has no vegetation and that it is not permeable.

Question 48

What are the two different type of stream flows and what is the difference?

Answer 48

1) Laminar (Smooth, organized, almost solid looking) | 2) Turbulent (Jagged, unorganized, looks like moving water)

Question 49

What are the 3 things that determine the velocity (stream flow)?

Answer 49

1) Gradient or slope 2) Channel characteristics including slope size, roughness 3) Discharge

Question 50

How does gradient effect velocity/stream flow?

Answer 50

The steepness of the gradient will determine how fast it goes because gravity is controlling it