earth science test chapter 5 (nooooo) :( Flashcards
what is mechanical weathering occur
when physical forces break into smaller pieces without changing the rocks mineral compostion
what are the three main causes of mechanical weathering
frost wedging, unloading, and biological activity
what is chemical weathering
the transformation of rock into one or more new compounds
what are two factors that affect the rate of weathering
the climate and rock characteristics
what are the three common types of soils
pedalfer pedocal laterite
what is the best type of soil to grow plants in
loam/topsoil
what is regolith
A layer of rock and mineral fragments that covers almost al the earth surface cuased by weathering.
What are the four major components of soil(what is humus)
mineral matter/broken down rocks, organic matter/humus(the decayed remains of organisms, water and air.
what are the most important factors in soil formation
parent material, time, climate, organisms, and slope
does soil texture color and compostiton stay the same as you go deeper underground
no
what is mass movement
the transfer of rock and soil downslope due to gravity
hwo do geologists classify mass movement
the kind of material that moves , how it moves, and the speed
What is exfoliation
A process in which unloading causes slabs of outer rock to separate and break loose
Does breaking rocks into smaller pieces increase or decrease the surface area
Increases
What is a common feature produced by exfoliation
A dome shaped rock formation
Which factor has the greatest effect on soil formation explain?
Climate Becuase if it’s cold the soil is going to be hard if it’s really hot the soil will not be good but if it sunny and moist etc the soil will be good
How does slope effect the formation of soil
If a slope is steep erosion is accelerated and it’s not good for plant growth cause of little moisture.
The direction too in the north if the slope faces south it receives more sunlight than north facing slopes/ same with south of slope is north recurve more sunlight
Describe the major characteristics of A B and C horizons
A. Commonly known as topsoil. Has lots of insects fungi and microorganisms. Lower part is a mix of mineral matter and organic matter
B. B/subsoil contains clay particles washed out of A horizon. The lower limit for most plant roots and burrowing animals.
C. Located between B and unweathered parent material. Contains some weathered parent material. This also better resembles the parent material than A and B horizons
Distinguish between pedalfer and pedocal
Pedalfer forms in temperate areas that get more than 63 cm of precipitation every year.
Pedocal is found in drier places that have grasses and brush vegetation. They generally have less clay than pedalfer.( have lots of calcite)
Describe laterite
Forms in hot wet tropical areas. They have a orange and red color. When dried it becomes very hard and practically waterproof. People in Southeast Asia used this for a long time.
What are three bad things about soil erosion
It removes the soil making land bad for agriculture. Creates new desserts. And pollutes waterways/ how water flows making floods more common.
Explain how weathering and mass movements produce most landforms.
The weathering breaks rocks while the mass movement moves it down slope. Then I think something happens
What is the force behind mass movements and what other things can trigger it.
Main thing - gravity
Others - saturation of surface materials with water, oversteep slopes, removal of vegetation, earthquakes
What are rockfalls/ rockslides differentiate
Rockfalls happen when rocks or fragments of rocks fall freely through the air.
Rockslide are when a block of materials move along a inclined surface. The slide includes segments of bedrock.
Distinguish between mudflows and earth flows
A mudflow is a bunch of minerals that contain a lot of water go downslope extremely fast.
And earthflow move relatively slowly with soil and rock materials saturated with water.
How do freezing and thawing contribute to creep
Becuase the freezing expands while the thawing contracts which allows particles to fall to lower levels. And each deez and thaw cycle moves particles downhill.
I’m which type of climate does mechanical weathering happen more rapidly
Warm and wet
What is soils texture determined by
Particle size
What are the five common mass movements
Rockfalls, slides, slumps, flows, creep
what is unloading
when the outer layers of rock break away from the rest of the rock
what is biological activity
the weakening and disintegration of rocks and minerals because of the activity of plants animals and microorganisms.
what is a slump
A type of mass movement that forms a C shape.
what is contour plowing
plowing along the contours of the land in order to minimize soil erosion.
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