CH 27 Flashcards
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 that is capable of supporting plant life
Soil
The removal of surface material through the process of weathering
Erosion
As rocks weather, erosional agents like water, ice, wind, and gravity move eroded materials from one place to another in a process called…
Sediment transport
When the erosional agent slows down or melts , it drops this sediment load in a process called…
Deposition
The land area that gathers water for a major river
Drainage basin
The movement of water parallel to the shoreline
Longshore current
Weathering
The process of physical or chemical breakdown of materials on Earth’s surface
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 type of change happens with mechanical weathering?
Physical changes
What type of change happens with chemical weathering?
Chemical
What are the 3 specific types of mechanical weathering?
Frost wedging, biological activity, and collision
What causes frost wedging?
When water collects in the cracks of rocks and freezes
What is the cycle called during frost wedging?
Freeze-Thaw Cycles
What causes biological activity?
Plant and animal activity
What causes weathering during collisions?
When rocks fall from a cliff or tumble through turbulent rivers
What are the 2 types of chemical weathering caused by?
Oxygen and water
What is the chemical process called this is caused by oxygen?
Oxidation
What is the chemical process called that is caused by water?
Hydrolysis
What is parent material?
The material from which soil forms
What are soil horizons?
The different layers of soil
How many soil horizons are there?
6
True or false. All soils contain every soil horizon.
False
What are the specific soil horizons?
O, A, E, B, C, and R
What does the first soil horizon contain?
Organic material
What is the 2nd horizon mostly made of?
Minerals
Which layer does leaching occur?
Horizon E
Which horizon collects materials from previous horizons?
Horizon B
Which layer is partially weathered bedrock?
Horizon C
Which layer is unweathered bedrock?
Horizon R
Which soil horizons make up the topsoil?
O and A
Which soil horizons make up the subsoil?
E and B
Which soil horizons make up the true soil?
O A B E
What is the difference between 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 will happen to the speed of the river?
The speed will decrease
What are tributaries?
Small streams that flow into larger rivers
What is a drainage basin?
Land area that gathers water for a major river
What is a drainage divide?
A boundary that separates distinct drainage basins
What does water flowing downhill eroding earth’s surface create?
Channels
Why are young rivers V-shaped?
Fast movement
Wide rivers with smooth and gentle slopes are
Mature
What type of land form is created when rivers flood and drop their sediment load?
Flood plains
What is a fan shaped sediment deposit that forms at the mouth of a river called?
Deltas
What are distributaries
Branching channels created by deltas
What are the two types of glaciers?
Valley and Continental
Where do valley glaciers form?
High mountainous regions
Where do continental glaciers form?
Colder climates that occupy large land areas
Where are the two continental glaciers located?
Greenland and Antarctica
What is a cirque?
A bowl shaped basin
What is an arete?
Long sharp ridgeline between valley glaciers
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 feed into large glaciers
What type of valley do tributary glaciers form?
Hanging valleys
On which side of a sand dune does erosion occur?
Windward side
What side of a sand dune does deposition occur?
Leeward side
What is deflation
The removal of small particles by wind
What is desert pavement?
The remaining surface when all small particles are removed
The shape and sizes of land forms eroded by wind depends on what?
Wind speed
amount of time the wind blows
sediment supply
What are three land forms created by wave erosion?
Coastal cliffs
Sea arches
Sea stacks
What are two land forms created by land deposition?
Sand bar and sand spits
What are some things that can cause mass wasting?
Snow, heavy rains, earthquakes, or human activity
What are some examples of mass wasting?
Rock slides
mudflows
landslides
What percent of water on Earth is salt water?
97%
What percentage of water on Earth is freshwater?
3%
Where is the majority of freshwater found?
In glaciers
Where is the smaller percentage of freshwater found?
Lakes, rivers, and as ground water
What is precipitation?
When water vapor in the air cools and condenses (rain, snow, sleet, and hail)
What is a runoff?
Where water runs off the land surface
What is infiltration?
The process by which water enters earth and becomes ground water
What is transpiration?
When plants release water vapor into the atmosphere through their leaves
What is evaporation?
When water enters the atmosphere as water vapor
What is condensation?
When water vapor collides with other water vapor molecules to form water droplets
What is the water cycle?
Water on the land that evaporates into the air and eventually makes its way back onto land
What is an unsaturated zone for groundwater storage?
A porous area where water passes through
What is a saturated zone for groundwater storage?
Where water completely fills the pore space
What is a water table?
The upper boundary of the saturated zone
What does it mean if sediment is permeable?
Water can infiltrate through it easier
What is an aquifer?
a rock unit that can transfer water through its pore space
What is the name of the Great Plains Aquifer?
Ogallala Aquifer
How many states does the Great Plains Aquifer run through?
8
What are the names of the states that the Great Plains Aquifer runs through?
South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, New Mexico, and Texas
What is an aquitard?
It keeps water confined
How are water springs formed?
Where water tables naturally meet Earth’s surface?
What is an artesian well?
Wells drilled into pressurized aquifers
What is a cone of depression?
The direction of the water flows down toward the well
The process of assigning an exact numerical age to an organism, an object,or event.
Absolute dating
The process of placing objects or events in their proper order in time.
Relative dating
States that the laws of nature operate today as they have in the past.
Uniformitarianism
States that in an undisturbed sequence of sedimentary rock layers, the youngest rocks will be at the top and the oldest rocks will be at the bottom.
Principle of superposition
Gaps in the rock record during which either erosion occurred or deposition was absent
Unconformity
The remains or traces of organisms found in the geologic rock record.
Fossil
