EOS 101 TEST 3 VERIFIED STUDY GUIDE
mass wasting - Answers - the downslope movement of rock, regolith, and soil under
the direct influence of gravity
weathering - Answers - The breaking down of rocks and other materials on the
Earth's surface
erosion - Answers - the removal and transport of material by wind, water, or ice
reasons to study mass wasting - Answers - 1. major geologic hazard - mass wasting
causes thousands of deaths each year
2. landform development - mass wasting, combined with actions of water, wind, and
ice, plays a major role in shaping the earth's surface
angle of repose - Answers - the maximum angle of a stable slope for loose
(unconsolidated) material; it is a function of grain size, shape, moisture
grain size and grain shape - Answers - larger grains can have a greater angle of
repose; more angular grains can have a greater angle of repose
moisture - Answers - dry grains are bound together by friction; small amounts of
water increase the cohesiveness among sand grains (greatest angle of repose);
saturation reduces friction and causes the sand to flow
controls and triggers of mass wasting - Answers - 1. water - reduces cohesion
between particles and adds weight to material
2. over-steeping of slope
3. vegetation removal - roots stabilize soil; removal by human or natural actions
leads to slope failure
4. earthquakes - ground shaking and/or liquefaction may trigger slope failure
risk factors for landslides - Answers - primary - elevation, rainfall
secondary - earthquakes, volcanoes
*greater than 30,000 mass wasting fatalities from 2004-2010
classification of types of mass wasting - Answers - 1. type of material - rock
(unconsolidated) vs. earth, mud, or debris
2. type of motion - fall vs. slope. vs. flow
3. rate of movement - fast vs. slow
fast forms of mass wasting (up to ~100km/hr) - Answers - - rockslide or rockfall
- debris flow, lahar
intermediate forms of mass wasting - Answers - - earthflow
- slump
slow forms of mass wasting (imperceptible: mm or cm/year) - Answers - - creep (ex.
frost heave)
, - solifluction (ex. regions of permafrost)
rockslide - Answers - fragments of detached rock slip along a planar surface
rockfall - Answers - fragments of detached rock fall from irregular surface
debris flow - Answers - water-laden masses of soil and rock fragments that rush
down mountainsides (often confined to canyons); result in alluvial fans
lahar - Answers - debris flow composed mostly of volcanic pyroclastic material (ash
and rock) in a slurry of water (can be initiated by volcanic eruptions that melt snow)
earthflow - Answers - commonly form on hillsides during heavy precipitation, material
moves as a viscous fluid
slump - Answers - movement of a mass of rock or unconsolidated material as a unit
along a curved surface of rupture
creep - Answers - The gradual downslope movement of soil or regolith
frost heave - Answers - an example of creep
solifluction - Answers - gradual downslope flow of water-saturated soil during warm
seasons in areas with permafrost; creates solifluction lobes
permafrost - Answers - permanently frozen layer of soil beneath the surface of the
ground; very sensitive to. heat
submarine landslides - Answers - landslides that take place underwater, can lead to
tsunamis; ex. Monterey Bay, California
the hydrologic cycle - Answers - the movement of water through the biosphere
total hydrosphere - Answers - - 97% ocean water
- 3% freshwater
total freshwater - Answers - - ~69% glaciers
- ~1% surface water
- ~30% groundwater
drainage basin - Answers - the land area that contributes water to a particular stream
or river
tributary - Answers - stream or river that flows into a larger stream/river
divide - Answers - an imaginary line, at highest surface elevation, separating one
basin from another
mass wasting - Answers - the downslope movement of rock, regolith, and soil under
the direct influence of gravity
weathering - Answers - The breaking down of rocks and other materials on the
Earth's surface
erosion - Answers - the removal and transport of material by wind, water, or ice
reasons to study mass wasting - Answers - 1. major geologic hazard - mass wasting
causes thousands of deaths each year
2. landform development - mass wasting, combined with actions of water, wind, and
ice, plays a major role in shaping the earth's surface
angle of repose - Answers - the maximum angle of a stable slope for loose
(unconsolidated) material; it is a function of grain size, shape, moisture
grain size and grain shape - Answers - larger grains can have a greater angle of
repose; more angular grains can have a greater angle of repose
moisture - Answers - dry grains are bound together by friction; small amounts of
water increase the cohesiveness among sand grains (greatest angle of repose);
saturation reduces friction and causes the sand to flow
controls and triggers of mass wasting - Answers - 1. water - reduces cohesion
between particles and adds weight to material
2. over-steeping of slope
3. vegetation removal - roots stabilize soil; removal by human or natural actions
leads to slope failure
4. earthquakes - ground shaking and/or liquefaction may trigger slope failure
risk factors for landslides - Answers - primary - elevation, rainfall
secondary - earthquakes, volcanoes
*greater than 30,000 mass wasting fatalities from 2004-2010
classification of types of mass wasting - Answers - 1. type of material - rock
(unconsolidated) vs. earth, mud, or debris
2. type of motion - fall vs. slope. vs. flow
3. rate of movement - fast vs. slow
fast forms of mass wasting (up to ~100km/hr) - Answers - - rockslide or rockfall
- debris flow, lahar
intermediate forms of mass wasting - Answers - - earthflow
- slump
slow forms of mass wasting (imperceptible: mm or cm/year) - Answers - - creep (ex.
frost heave)
, - solifluction (ex. regions of permafrost)
rockslide - Answers - fragments of detached rock slip along a planar surface
rockfall - Answers - fragments of detached rock fall from irregular surface
debris flow - Answers - water-laden masses of soil and rock fragments that rush
down mountainsides (often confined to canyons); result in alluvial fans
lahar - Answers - debris flow composed mostly of volcanic pyroclastic material (ash
and rock) in a slurry of water (can be initiated by volcanic eruptions that melt snow)
earthflow - Answers - commonly form on hillsides during heavy precipitation, material
moves as a viscous fluid
slump - Answers - movement of a mass of rock or unconsolidated material as a unit
along a curved surface of rupture
creep - Answers - The gradual downslope movement of soil or regolith
frost heave - Answers - an example of creep
solifluction - Answers - gradual downslope flow of water-saturated soil during warm
seasons in areas with permafrost; creates solifluction lobes
permafrost - Answers - permanently frozen layer of soil beneath the surface of the
ground; very sensitive to. heat
submarine landslides - Answers - landslides that take place underwater, can lead to
tsunamis; ex. Monterey Bay, California
the hydrologic cycle - Answers - the movement of water through the biosphere
total hydrosphere - Answers - - 97% ocean water
- 3% freshwater
total freshwater - Answers - - ~69% glaciers
- ~1% surface water
- ~30% groundwater
drainage basin - Answers - the land area that contributes water to a particular stream
or river
tributary - Answers - stream or river that flows into a larger stream/river
divide - Answers - an imaginary line, at highest surface elevation, separating one
basin from another
