ch 27 Flashcards
what is the process that involves the physical or chemical breakdown of materials on earth’s surface?
weathering
a mixture of weathered rock, organic matter, water and air capable of supporting plant life
soil
the removal of surface material through the process of weathering
Erosion
erosional agents like wind, water, ice, and gravity move eroded materials from one place to another
sediment transport
the erosional agents slow down or melts and drops sediment loads in the process
deposition
the land area that gathers water for a major river
drainage basin
movement of water parallel to the shoreline
longshore current
Do rocks weather at the same rate?
no
What are the two main factors that determine how fast a rock will weather?
rock type and landscape
What are the two types of weathering?
mechanical and chemical
What types of change happens with mechanical weathering?
physical weathering
What type of change happens with chemical weathering?
chemical weathering
What are the 3 types of specific mechanical weathering?
frost wedging, biological activity, and collisions
what causes frost wedging?
water freezes in the cracks of rock and cracks the rock even more
What is the cycle called during frost wedging?
freeze thaw cycle
What causes biological activity?
plants and animals
What causes weathering during collisions?
rock fall from cliffs or tumble through turbulent rivers
What is parent material?
Is what soil is formed from
What are the 2 types of chemical weathering caused by?
oxygen and water
What is the chemical process called that is caused by oxygen?
oxidation
What is the chemical process called that is caused by water?
hydrolysis
What are soil horizons?
All the different layers of soil
How many soil horizons are there?
6
True of false All soils contain every soil horizon
false
What are the specific soil horizons?
o,a,e,b,c,r
What does the first soil horizon contain?
organic material
What is the second horizon mostly made up of?
minerals
Which layer does leaching occur?
E
Which horizon collects materials from previous horizons?
B
Which layer is partially weathered bedrock?
C
Which layer is unweathered bedrock?
R
Which soil horizons make up topsoil?
O and A
Which soil horizons make up the subsoil?
B and E
Which soil horizons make up the true soil?
C and R
What is the difference of weathering and erosion?
Weathering is the breakdown of materials and erosion is the removal of surface material
If the slope of a river decreases what happens to the speed of a rivers
the rives speed decreases
Small streams that flow into larger rivers are called
tributaries
Land areas that gather water for a major river is called a
drainage basin
a boundary that seperates distinct drainage basins is called a
drainage divide
as water flows downhill under the influence of gravity, water erodes earth’s surface creating
channels
Young rivers and _____ due to the fast movement
V-shaped
___ rivers are wide with smooth and gentles slopes
Mature
When rivers flood and drop their sediment load which type of land form is created
flood planes
What is a fan shaped sediment deposit that forms at the mouth of a river
Delats
What are distributaries
the branching channels from deltas
the mouth of a river or stream enters dry land
Alluvial fans
What are the two types of glaciers?
Valley and continental
Where do valley glaciers form?
In high mountainous regions
Where do continental glaciers form?
colder climates and they occupy large land areas
Where are the two continental glaciers located?
one in greenland and one in antartica
What is a cirque?
bowl shaped basin
What is an arete?
2 tributary valley glaciers meet and create a long sharp ridge line
What is a horn in a mountainous region?
sharpened peaks
What shape of valley do valley glaciers form?
u-shaped valleys
What are tributary glaciers?
small glaciers that lead into large glaciers
What type of valleys do tributary glaciers form?
hanging valleys
which side of a sand dune does erosion occur?
windward side
Which side of a sand dune does deposition occur?
leeward side
what is the removal of small particles by wind, leaving heavier particles behind?
deflation
what is it when small particles are removed and its just the remaining surface?
desert pavement
what do the shape and sizes of land forms depend on?
3 things
wind speed
amount of time the wind blows
sediment supply
what are three landforms that are created due to wave erosion?
coastal cliffs
sea arches
sea stacks
what are two landforms created by wave deposition?
sand bars
sand spits
what is a sand bar?
landforms that are parallel to the shoreline
what is a sand spit?
like the sand bar but curves back toward the land
what can cause mass wasting?
snow, heavy rains, earth quakes or human activity
process by which water enters Earth and becomes ground water
infiltration
What is the upper boundary of the saturated zone called
water table
a rock unit that can transfer water through its pore space
aquifer
the percentage of a materials total volume and pore space
porosity
The process of assigning an exact numerical age to an organism, object or event
absolute dating
the process of placing object or events in the proper order in time
relative dating
states that the laws of nature operate today has they have in the past
uniformitarianism
states that undisturbed sediment layers the youngest will be at the top and the oldest at the bottom
principle of super position
gaps in the rock record when either erosion occurred or deposition was absent
unconformity
remains or traces of organisms found in geological rock record
fossils
