APES Unit 4 Study Guide Exam Questions and
Answers
What are the layers of the earth? - -15; Crust, mantle, outer core and inner core
-What are the 3 major processes in Earths geologic cycle? - -Tectonic plates, rock cycle &
soil formation
-Define the theory of plate tectonics - -The theory that the lithosphere of the earth is
divided into plates, most of which are in constant motion
-Explain the movement of divergent plate boundaries and give an example - -An area
beneath the ocean where tectonic plates move away from each other. Ex: Seafloor
spreading
-Explain the movement of convergent plate boundaries and give an example - -An area
where plates move toward one another and collide. Ex: Subduction or continental collision
-Explain the movement of transform fault boundaries and give an example - -Are where
two tectonic plates meet and slip and grind alongside one another. Ex: Earthquake
-Define volcano - -A vent in the surface of earth that emits ash, gases, or molten lava.
(Occurs as a plate moves over a hot spot and heat from the mantle melts the crust)
-Define earthquake - -The sudden movement of earths crust caused by a release of
potential energy along a geologic fault and usually causing a vibration or trembling at
earths surface.
-Define richter scale - -A scale that measures the largest ground movement that occurs
during an earthquake
-How many times greater is an earthquake with a magnitude of 8 than an earthquake with
a magnitude of 5? - -8-5=3. Add 3 zeros. Put a 1 in front.
>1,000<
-Explain the rock cycle - -The continuous formation and destruction of rock on and below
the surface of earth
-What are the 3 types of rocks and how are they formed? - -1) Igneous rock-formed from
cooling magma
2) Sedimentary rock-Formed when dissolved minerals seep through sediment layers and
act as a kind of glue, crystallizing and binding sediment particles together. (MAJOR SINK
FOR PHOSPHORUS)
, 3) Metamorphic rock- Formed by great heat and/or pressure that reshapes crystals within
the rock and changes its appearance and physical properties
-What is a mineral - -A solid chemical substance with a uniform, often crystalline,
structure that forms under specific temperatures and pressures.
-What is the difference between physical and chemical weathering? Give examples of each
- -1)Physical weathering is the mechanical breakdown of rocks and minerals. Ex: Wind or
rain
2)Chemical weathering is the breakdown of rocks and minerals by chemical reactions, the
dissolving of chemical elements from rock, or both. Ex: Acid rain
-Explain the formation of acid rain - -Sulfur is emitted into the atmosphere and reacts with
oxygen to create sulfur dioxide. It then turns into sulfuric acid which lowers the pH of the
rain.
-Explain erosion - -The removal of material from one place and its transport to another by
the action of wind or water
-In what ways do humans accelerate the rate of erosion? - -1) Overcultivating fields
through poor planning or excessive tilling
2) Overgrazing rangeland with more livestock than the land can support
3) Clearing forests on steep slopes or with large clear cuts
-Define soil - -A complex plant supporting system consisting of disintegrated rock, organic
matter, air, water, nutrients, and microorganisms.
-What are the 5 factors that determine the properties of soil? - -1)Organisms: plants and
decomposers add organic matter to soil over time
2)Climate: soil forms faster in warm, wet climates (heat and moisture speed most physical,
chemical and biological processes)
3)Topography: hills and valleys affect exposure to sun, wind, and water, and they influence
how soil moves.
4)Parent Material: its attributes influence properties of the resulting soil
5)Time: soil formation can take decades, centuries or millennia
-What are the soil horizons? - -O horizon-organic (litter layer)
A horizon-topsoil
E horizon-eluviated (leaching layer)
B horizon-subsoil
C horizon-weathered parent material
R horizon-rock (parent material)
-What is "Zone of Leaching" - -E horizon where minerals are generally transported
downward as a result of leaching
Answers
What are the layers of the earth? - -15; Crust, mantle, outer core and inner core
-What are the 3 major processes in Earths geologic cycle? - -Tectonic plates, rock cycle &
soil formation
-Define the theory of plate tectonics - -The theory that the lithosphere of the earth is
divided into plates, most of which are in constant motion
-Explain the movement of divergent plate boundaries and give an example - -An area
beneath the ocean where tectonic plates move away from each other. Ex: Seafloor
spreading
-Explain the movement of convergent plate boundaries and give an example - -An area
where plates move toward one another and collide. Ex: Subduction or continental collision
-Explain the movement of transform fault boundaries and give an example - -Are where
two tectonic plates meet and slip and grind alongside one another. Ex: Earthquake
-Define volcano - -A vent in the surface of earth that emits ash, gases, or molten lava.
(Occurs as a plate moves over a hot spot and heat from the mantle melts the crust)
-Define earthquake - -The sudden movement of earths crust caused by a release of
potential energy along a geologic fault and usually causing a vibration or trembling at
earths surface.
-Define richter scale - -A scale that measures the largest ground movement that occurs
during an earthquake
-How many times greater is an earthquake with a magnitude of 8 than an earthquake with
a magnitude of 5? - -8-5=3. Add 3 zeros. Put a 1 in front.
>1,000<
-Explain the rock cycle - -The continuous formation and destruction of rock on and below
the surface of earth
-What are the 3 types of rocks and how are they formed? - -1) Igneous rock-formed from
cooling magma
2) Sedimentary rock-Formed when dissolved minerals seep through sediment layers and
act as a kind of glue, crystallizing and binding sediment particles together. (MAJOR SINK
FOR PHOSPHORUS)
, 3) Metamorphic rock- Formed by great heat and/or pressure that reshapes crystals within
the rock and changes its appearance and physical properties
-What is a mineral - -A solid chemical substance with a uniform, often crystalline,
structure that forms under specific temperatures and pressures.
-What is the difference between physical and chemical weathering? Give examples of each
- -1)Physical weathering is the mechanical breakdown of rocks and minerals. Ex: Wind or
rain
2)Chemical weathering is the breakdown of rocks and minerals by chemical reactions, the
dissolving of chemical elements from rock, or both. Ex: Acid rain
-Explain the formation of acid rain - -Sulfur is emitted into the atmosphere and reacts with
oxygen to create sulfur dioxide. It then turns into sulfuric acid which lowers the pH of the
rain.
-Explain erosion - -The removal of material from one place and its transport to another by
the action of wind or water
-In what ways do humans accelerate the rate of erosion? - -1) Overcultivating fields
through poor planning or excessive tilling
2) Overgrazing rangeland with more livestock than the land can support
3) Clearing forests on steep slopes or with large clear cuts
-Define soil - -A complex plant supporting system consisting of disintegrated rock, organic
matter, air, water, nutrients, and microorganisms.
-What are the 5 factors that determine the properties of soil? - -1)Organisms: plants and
decomposers add organic matter to soil over time
2)Climate: soil forms faster in warm, wet climates (heat and moisture speed most physical,
chemical and biological processes)
3)Topography: hills and valleys affect exposure to sun, wind, and water, and they influence
how soil moves.
4)Parent Material: its attributes influence properties of the resulting soil
5)Time: soil formation can take decades, centuries or millennia
-What are the soil horizons? - -O horizon-organic (litter layer)
A horizon-topsoil
E horizon-eluviated (leaching layer)
B horizon-subsoil
C horizon-weathered parent material
R horizon-rock (parent material)
-What is "Zone of Leaching" - -E horizon where minerals are generally transported
downward as a result of leaching
