Earth Science Final Review Part 2

Question 1

Where do glaciers form? How do glaciers form?

Answer 1

Form in places that have cold temperatures year-round. The cold keeps fallen show from completely melting and each year the snow that has not melted accumulates in an area called a snowfield. The total thickness of the snow layer increases as the years pass and a glacier begins to form. The weight of the top layers of snow exert enough downward pressure to force the snow below to recrystalize into ice.

Question 2

Compare and contrast valley glaciers with continental glaciers.

Answer 2

Valley- glaciers that form in valleys in high mountainous areas.
Continental- cover broad continent sized areas.

Question 3

What are four features of glaciers?

Answer 3

• Arête
• Cirque
• Hanging Valley
• Horn

Question 4

What are four landforms produced by glaciers?

Answer 4

1) moraines
2) outwash
3) drumlins
4) eskers

Question 5

What are moraines?

Answer 5

Ridges consisting of till deposited by glaciers.

Question 6

What is outwash?

Answer 6

Sediments deposited by meltwater.

Question 7

What are drumlins?

Answer 7

Elongated landforms formed when glaciers move over older moraines.

Question 8

What are eskers?

Answer 8

Long winding ridges of layered sediments that are deposited by streams flowing under a melting glacier.

Question 9

What are four properties of minerals used for identification?

Answer 9

1) cleavage
2) hardness
3) lustre
4) streak

Question 10

What are the two ways that minerals form?

Answer 10

From magma or from solution

Question 11

How do minerals form from magma?

Answer 11

When magma cools as it is forced upwards into cooler layers of Earth’s interior, the compounds in magma no longer move freely and begin to interact chemically to form minerals.

Question 12

How did minerals form from solution?

Answer 12

A given volume of water can only dissolve so much of a solid before the water becomes saturated. The saturated water can then not dissolve any more solids. If a solution becomes over saturated with another, mineral crystals begin to precipitate. Minerals can also form when elements dissolve in a supersaturated solution. when liquid evaporates from the solution, the elements remain behind and may begin to arrange into crystals.

Question 13

Compare intrusive and extrusive igneous rocks.

Answer 13

Intrusive- coats-grained igneous rocks that cool slowly beneath Earth’s surface.
Extrusive- fine-grained igneous rocks that cool quickly on Earth’s surface.

Question 14

What are the factors that affect magma formation?

Answer 14

• temperature
• pressure
• water content
• mineral content

Question 15

Compare partial melting with fractional crystallization.

Answer 15

Partial melting- the process whereby some minerals left at low temperatures while other minerals remain solid. As each group of minerals melts, different elements are added to the magma, changing its composition
Fractional crystallization- when magma cools it crystallizes in the reverse order of partial melting. The process wherein different I reals form as different temperatures. As each group of minerals crystallizes, the changes occur because as each group crystallizes it removes elements from the remaining magma instead of adding new elements.

Question 16

What are some common igneous rock examples?

Answer 16

Granite, gabbro, pumice, rhyolite

Question 17

What are some common uses for igneous rocks?

Answer 17

Construction, memorials, kitchen tiles, countertops.

Question 18

List and describe the steps in the formation of clastic sedimentary rocks.

Answer 18

Erosion- the removal and movement of surface materials from one location to another.
Deposition- sediments are deposited when transport stops. Particles then settle out, forming layers of sediment.
Burial- most sediments are deposited on Earth’s surface in depressions called sedimentary basins which contain layers of sediments that are more than 8 km thick. More layers are deposited and lithification takes place to to increasing pressure and temperature.
Cementation- occurs when mineral growth cements sediment grains together into solid rock.
Lithification- begins with compaction as the weight of overlying sediments forces the sediment grains closer together, causing the physical changes.

Question 19

How do chemical sedimentary rocks form?

Answer 19

When the concentration of dissolved minerals in a body of water reaches saturation, crystal grains precipitate out of the solution and settle to the bottom. Layers of the chemical sedimentary rocks that form as a result are called evaporites.

Question 20

Classify and name examples of clastic, chemical and organic sedimentary rock.

Answer 20

Rock Type:
Clastic: coarse, medium, or fine grained
Chemical: calcite, halite, and gypsum
Organic: calcium carbonate (shells), plant matter
Rock Name:
Clastic: conglomerate or breccia, sandstone, siltstone, shale
Chemical: limestone, rock salt, rock gypsum
Organic: limestone, coal
Method of formation:
Clastic: formed from the lithification of clastic sediments
Chemical: formed from the precipitation of dissolved minerals from water
Organic: formed from the accumulation and lithification of remains of living things.

Question 21

Why are sedimentary rocks important for understanding the Earth’s past and natural resources?

Answer 21

Sedimentary rock contain valuable information about the Earth’s history. They contain fossils, preserve the remains of plants and animals, indicate the location and direction of ancient rivers, and the wave and wind direction over lakes. Many of the natural resources used by humans come from sedimentary rocks, such as oil, natural gas, coal, uranium, phosphate, iron, and limestones.

Question 22

What are the ways that metamorphic rocks form?

Answer 22

Regional Metamorphism- when high temperatures and pressure affect large regions of Earth’s crust. Can be low, intermediate, or high grade which will reflect the intensity of temperature and pressure.
Contact Metamorphism- when molten rocks come in contact with solid rocks. High temperatures and moderate-to-low pressure from the mineral assemblages that are characteristic of contact metamorphism.
Hydrothermal Metamorphism- when very hot water reacts with rock and laters its chemistry. Hydrothermal metamorphism can dissolve some minerals, break down others, and deposit new ones.

Question 23

What are some common metamorphic rocks?

Answer 23

Marble, schist, quartzite

Question 24

What are the layers of the Earth?

Answer 24

Lithosphere
-crust
-upper mantle
Mantle
Asthenosphere
Core
-inner core
-outer core

Question 25

What was Wegener’s theory of continental drift?

Answer 25

Wegener’s proposed that the supercontinent Pangaea began to break apart 200 million years ago and formed the present landmasses.

Question 26

What are the four pieces of evidence for continental drift?

Answer 26

1) the continent puzzle
2) matching fossils
- fossil evidence for continent drift includes several fossil organisms found on different landmasses.
3) rock types and structures
- rock evidence for continental drift exists in the form of several mountain belts that end at one coastline, only to reappear on a landmass across the ocean
4) ancient climates
- stuff buried under would be similar

Question 27

What are the three types of plate boundaries?

Answer 27

Convergent- form when two plates move together
Divergent- (also called spreading centers) are the places where two plates move apart.
Transform fault- are margins we here two plates friend past each other without the production or destruction of the lithosphere.

Question 28

What are oceanic ridges?

Answer 28

Continuous elevated zones on the floor of all major ocean basins. The rifts at the crust of ridges represent divergent plate boundaries.

Question 29

What are rift valleys?

Answer 29

Deep faulted structures found along the axes of divergent plate could arise. They can develope on the Seafloor or on land.

Question 30

What is Seafloor spreading?

Answer 30

Produces new oceanic lithosphere.

Question 31

What are continental rifts?

Answer 31

When spreading centers develope within a continent, the landmasses may split into two or more smaller segments, forming a rift.

Question 32

What is a subduction zone?

Answer 32

Occurs when one oceanic plate is forced down into the mantle beneath a second plate.

Question 33

What are oceanic-continental convergent boundaries?

Answer 33

Denser oceanic slate sinks into the asthenosphere and pockets of magma develope and rise. Continental volcanic arcs form in part by cold anics activity caused by the subduction of oceanic lithosphere beneath a continent.
Examples include the Andes, Cascades, and the Sierra Nevada.

Question 34

What are oceanic-oceanic convergent boundaries?

Answer 34

Two oceanic slabs converge and one descends beneath the other. This kind of boundary often forms volcanoes on the ocean floor. Volcanic island arcs form as volcanoes emerge from the sea. Examples include the Aleutians, Mariana, and the Tonga islands.

Question 35

What are continental-continental convergent boundaries?

Answer 35

When sub ducting plates contain continental materials, two continents collide. This kind of boundary can produce new mountain ranges, such as the HImalayas.

Question 36

What are transform fault boundaries?

Answer 36

At a transform fault boundary, plates grind past each other without destroying the lithosphere.

Question 37

What are transform faults?

Answer 37

Most join two segments of a mid ocean ridge. At the time of formation, they roughly parallel the direction of plate material. They aid the movement of oceanic crust material.