Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
Talus
|
loose material accumulated by gravity
|
|
|
Mass wasting
|
-downslope movement of earth materials influenced by gravity
|
|
|
Creep
|
Mass wasting that moves slowly
|
|
|
Catastrophic
|
Mass wasting that happens at once
e.g. rock fall |
|
|
Controls on mass wasting
|
(1) angle of slope
(2) type of earth material (3) the orientation of surfaces in earth materials (4) involvement of water |
|
|
Normal stresses
|
Holds rocks together
|
|
|
Shear stress
|
wants to tear rocks apart
|
|
|
Controls and Triggers for mass wasting
|
1. Gravity
2. Saturation of material with water 3. Oversteepenning of slopes 4. Removal of anchoring Vegetation 5. Ground vibrations |
|
|
Ductile
|
Elastic, Easy to bend
|
|
|
Brittle
|
Hard, snaps
|
|
|
Water and Mass wasting
|
1) Water unconsolidates material (reduces cohesiveness)
2) Water makes dry clay ductile 3) Water reduces all normal stress 4) Water adds weight to permeable materials |
|
|
Earthflow
|
Water+ permeable soil
|
|
|
Hydrologic cycle
|
Percolation
Evaporation Condensation Precipitation |
|
|
Concept of Base sea level
|
Level below a stream cannot erode
|
|
|
River discharge
|
Q= A*V
|
|
|
Types of Flood
|
Riverine - regional
Flash - localized Storm surge - coastal |
|
|
Porosity
|
Amount of open space within earth
|
|
|
Permeability
|
Ability to allow water flow
|
|
|
Ground water discharge
|
High watertable
goes into stream |
|
|
Ground water recharge by infiltration
|
Low watertable
stream water recharges ground water |
