8.1-8.4 Notes Flashcards
Breaking a rock into smaller pieces without changing it’s chemical composition
Physical weathering
Breaking a rock into smaller pieces by changing it’s chemical composition (it forms a new material)
Chemical weathering
Which happens best in a hot wet climate?
Chemical weathering
rocks break apart when liquid water seeps into cracks then freezes and expands
frost wedging
roots of plants grow and move underground causing enough pressure that the rocks break
root action
when rocks collide resulting in the break and wearing away of rocks
Abrasion
how are rocks different when abrasion occurs?
rounded and smaller
the chemical reaction of rain water with another substance (Nitric and sulphuric acids)
Hydrolosis
The chemical reaction of oxygen with another substance (iron oxide rust)
Oxidation
when carbon dioxide is dissolved in groundwater it creates a weak acid that breaks down various clay materials (limestone)
Carbonic acid
as rocks are weathered they usually get…
smaller, rounder, and smoother
A solid rock has the ____ surface area
Least (the interior is protected)
A ground up rock has the ___ surface area
greatest (the interior can now be attacked)
The more surface area is exposed the ___ weathering will occur
More
A mineral’s ___ determines it’s resistance to weathering
hardness
what climates favor physical weathering
Cold and/or dry
Frost action works best where?
High elevations because the temp fluctuates above and below freezing
what climates favor chemical weathering
warm and wet
where do chemical reactions occur faster?
warmer environments
where do chemical reactions occur faster?
warmer environments
where does physical weathering happen the most
cold and wet (good for frost wedging)
which climates have less weathering and erosion?
arid
dry climates have what type of rocks
angular
what can chemically weather limestone and form caves
acid rain
when particles are broken into smaller pieces the surface area
increases
as the particle size decreases the rate of weathering
increases
the top layer of Earth’s surface consisting of sediment mixed with organic material (dead organisms and their poop)
Soil
texture refers to the
particle sizes
Soil texture directly affects what
the soil’s ability to support plant life
soil has 4 major components
air, water, minerals, and organic material
all of the layers that make up the soil in the area
soil profile
soil forms in layers called
horizons
Immature soils only have _ horizons
2
Mature soil has at least _ horizons
3 (topsoil, subsoil, and weathered bedrock)
the resistance of the rock that created the sediment in the soil
Parent material
the more time soil has to mature the ____ it will be
thicker
A hot wet climate produces what soil
chemically weathered soil
a cold dry climate produces what type of soil
physically weathered
what is the main source of organic material
plants
what decomposes the organic matter into useable nutrients
microorganisms
what mixes everything together
burrowing animals
a soil formed by the weathering of the bedrock found beneath it
residual soil
transported soil
soil that has been moved from it’s original location
Most NYS soil is
transported from up north
breaks down rocks
weathering
what carries the pieces away
erosion
what is when rocks are left behind
deposition
what is the result of weathering and biological activity over long periods of time
soil
what are the broken down pieces of rock
sediments
what is classified based on their particle size
sediments
mixture of weathered rock pieces and remains of dead plants and animals
soil
erosion will equal what
depostion
erosion equalling deposition is what
dynamic equillibrium
5 agents of deposition
Gravity, wind, waves, glaciers, and running water
the transfer of rock and soil down the slope due to gravity
mass movement
what causes mass movement to happen
earthquakes, water, oversteepened slopes, removal of vegetation
when rock fragments move freely through the air
rockfalls
what occurs from weathering of rock caused by frost action or biological activities
rockfalls
the sudden movement of rock material along a flat inclined surface seen in high mountainous areas
rock slides
the downward movement of material along a curved surface
Slumps
how fast do slumps move
not very fast
slumps are seen when soil is high in what
clay (smallest particles)
movements of materials that contain large amounts of water
flows
move quickly, occurs after/during heavy rains or rapid snow melt
mudflows
move slowly, occurs on hillsides in wet regions
earthflows
the slowest type of mass movement, occurs due to freezing and thawing
creep
freezing does what to the water in soil
expands
thawing does what to the soil
contracts, lowering particles to a slightly lower position from when they started
deposition due to gravity causes
piles of unsorted angular rock fragments
what is the force behind all erosion
gravity
what is the movement of sediments
erosion
earth materials move downslope because of gravity (aka landslide)
mass movement
gravity leaves behind what type of rocks
angular (not round) and unsorted rocks (different sizes all mixed up)
