Exam 2 part 3 Flashcards
What happens when a volcano goes extinct?
The tectonic around it become unmovable
Where are most volcanoes located?
Either in or near ocean basins
Basaltic rocks are oceanic or continental?
They are both
Where is the greatest volume of volcanic rocks formed?
At oceanic ridges
What happens when the lithosphere is being pulled apart?
Decompression melting occurs at the mantle and large quantities of basaltic magma is produced
Where is the world’s most explosive volcanoes and what is their composition?
The ring of fire and their composition is andesite
What is all around the pacific basin?
Subduction zones
What is intraplate volcanism?
When a volcano occurs within a tectonic plate instead of at the edge of the plate
How is it possible for a volcano to occur in the middle of a tectonic plate?
It is possible through mantle plumes creating a hot spot
What does a intraplate volcano produce?
Basaltic magma sources in the oceanic crust, can even form land such as Hawaii and Iceland
How many hotspots are there is the world?
There are over 20
How do igneous rocks form definition/texture?
Through cooling and solidification
What creates soil?
The weathering of rocks at the surface, their physical break down is what makes soil
What are the 3 external processes of weathering?
1) Weathering
2) Erosion
3) Mass wasting
What is erosion and what are the four processes of it?
It is the physical removal of material by mobile agents such as water/wind/ice/gravity.
What is mass wasting?
The transfer of rock and soil down slope under the influence of gravity.
What is the difference between disintegration and decomposition?
Disintegration is the physical break down of material and decomposition is the chemical alteration of materials
What is the most common land form transportation agent?
Rivers
What is the first thing to happen after weathering takes place?
Gravity
What are creeps and what do they do?
They are land movements, they’re no threat to human life but they do cause more damage than any landslide
What are the two types of weathering?
Mechanical and Chemical
What are the 4 types of mechanical weathering?
1) Frost wedging
2) Unloading
3) Thermal expansion
4) Biology activity
What is unloading?
Pressure being released and causing the rock to crack
What is thermal heat in weathering?
As the rock gets hotter it starts to expand on the outside and causing the material to crack
What is the most important chemical weathering agent?
Water. It is responsible for the transport of ions molecules involved in chemical process
What is the most common mineral group?
Feldspar (Silicate)
What is an important byproduct of chemical weathering
Clay
What are the 3 major processes of chemical weathering and what do they do?
1) Dissolution (Small amounts of acid in water)
2) Oxidation (Electrons lost from one element/rust)
3) Hydrolysis (Reaction of any substance in water)
What is the most stable form of chemical weathering?
Spheroidal weathering, where something is turned into a sphere and gets smaller and smaller
What are the 3 factors affecting weathering?
1) Surface area (Deterioration)
2) Climate (Temperature and moisture)
3) Differential weathering (rocks don’t weather at same time)
What rocks are easy to deteriorate in water/acid?
Anything with calcite
What is the most effective factor of chemical weathering?
Climate/temperature and moisture
What are the 4 parts to soil
1) Air
2) Minerals
3) Water
4) Organic matter
What is regolith?
Mineral fragments produced by weathering, they help support the growth of plants
What is humus and why is it important?
Decayed animal and plant remains, essential component to regolith
What are pores?
They are water and air spaces in the soil
What are the five things that can affect soil composition?
1) Parent material
2) Time
3) Climate
4) Plants and animals
5) Topography
What is the difference between residual and transported soil?
Residual soil is soil that has the clay and quartz left over from just weathered bedrock. Transported soil is soil that transports onto sediment
What does it mean when you are describing climate as a factor that can affect soil composition?
Climate basically describes the temperature and water that your soil has within it’s region
What do plants and animals do to a soil’s composition?
They influence the soil’s physical and chemical properties
How does topography change a soil’s composition?
If the topography around the soil is steep, like a steep slope then the soil will be poorly developed
What is the best topography for soil?
Flat to undulating upland surface
What’s the most important plant to affect soil composition and what is the most important animal to affect soil composition?
Plant: Leaves
Animal: Worms
Why do steep slopes have poorly developed soils?
Because the gravity pulls material down before is can become soil
Name the 6 soil horizons in order.
1) O
2) A
3) E
4) B
5) C
6) R
What does each soil horizon represent?
O and A: Top soil E: Leaching area B: Accumulation C: Parent Material R: Bedrock
What type of soil is north Ohio and why?
It’s transported soil from glacial till.
What are the 4 things that the natural rates of soil erosion depend on?
1) Soil characteristics
2) Climate
3) Slope
4) Type of vegetation
Is there more soil erosion than there is soil formation?
Yes.
