Units 1-5: Geomorphology

Question 1

What is gemorphology?

Answer 1

Study of the form and structure of the earth and the process that shape them

Question 2

The crust (which is thickest under the continents and thinnest under the ocean) is split into what?

Answer 2

Tectonic plates

Question 3

What is the Moho Discontinuity?

Answer 3

The boundary between the crust and the mantle

Question 4

What is the asthenosphere?

Answer 4

the upper mantle of the earth

Question 5

What is NiFe? What is SiAl? What is SiMa?

Answer 5

Nickel and Iron (core)
Silicon and Aluminum (Continental crust)
Silicon and Magnesium (Oceanic crust)

Question 6

How is sedimentary rock formed?

Answer 6

Formed from sediments deposited by wind, water or ice. They are compacted together forming strata

Question 7

How is metamorphic rock formed?

Answer 7

It is formed when igneous or sedimentary rock undergoes a change cause by heat or pressure

Question 8

How is igneous rock formed?

Answer 8

It is formed when molten rock called magma rises through the crust, cools then crystalizes. The slower it cools the larger the crystals that form

Question 9

Explain resistance in rocks.

Answer 9

Some rocks are more resistance than others meaning they erode more slowly and have a steeper slope, eg sandstone. (Shale is soft)

Question 10

Explain permeability. (opposite is impermeable rock)

Answer 10

The ability of a rock to let water pass through. Water can pass through tiny spaces between cracks or sediments in a rock

Question 11

What is the continental drift theory?

Answer 11

Theory suggested by Alfred Wegener that tectonic plates move and are not fixed. This was later expanded into the Plate Tectonic theory.

Question 12

Fill in the blanks:

200 million years ago there was a super continent called _____ which later broke apart into ____ and ____. These then broke into the continents we know today.

Answer 12

Pangea
Laurasia
Gondwanaland

Question 13

6 pieces of evidence of plate tectonics

Answer 13

1. Coastlines (fit together)
2. Fossils (same species that cant swim was found on multiple continents)
3. Plants (plant life is very similar on different continents)
4. Rocks (mountain ranges with similar rock formations form on different continents)
5. Deposits (coal deposits formed from the same thing are found on different continents)
6. Glacial deposits (Brazil and West Africa have the same glacial deposits meaning they were covered in the same ice sheet)

Question 14

What causes the plates to move?

Answer 14

Convectional currents, they are formed from heat in the mantle

Question 15

What is the cause of faulting?

Answer 15

Great pressures causes rocks to bend then fracture and shift

Question 16

What is a tensile force? (Normal fault)

Answer 16

moving away from each other. One side falls down

Question 17

What is a compression force? (Reverse fault)

Answer 17

Moving towards each other. One side is pushed up

Question 18

What are lateral/horizontal forces? (Strike slip fault)

Answer 18

(eg San Andreas fault) Move past each other

Question 19

How is a rift valley formed? OR graben

Answer 19

caused by normal fault or tensile forces

Question 20

How is a block mountain formed? OR horst

Answer 20

caused by reverse fault or compression forces

Question 21

Describe a horst.

Answer 21

roof with a floor on either side

Question 22

Describe a graben.

Answer 22

floor with a roof on either side

Question 23

Labels in normal / reverse faults

Answer 23

Exposed rock - fault scarp
Rock pushed up/falling down - roof/hanging wall
Other piece of rock - floor / footwall

Question 24

Why are rift valleys important?

Answer 24

Helps with farming, attracts tourists, the steep slopes help to generate HEP,

Question 25

Focus definition

Answer 25

The place where earthquakes start (underground)

Question 26

Epicenter definition

Answer 26

The place directly above the focus (above ground)

Question 27

Seismic wave definition

Answer 27

Movement of ground traveling through the earths surface in the form of a wave

Question 28

Seismograph definition

Answer 28

Instrument used to measure seismic waves

Question 29

Richter scale definition

Answer 29

Scale used to compare strengths of earthquakes

Question 30

Effect tsunamis has on people

Answer 30

Death, loss of resources and possessions, land is eroded and places can get cut off

Question 31

Why are earthquakes less devastating in developed countries?

Answer 31

They have early warning systems and technology that can predict them, buildings are more resistant to them, emergency services are better and more equipped, people are more educated about how to deal with these situations

Question 32

How to reduce impact of earthquakes?

Answer 32

Identify high risk areas and avoid them, better prepare emergency services, build dams at fault lines to absorb shock, strengthen infrastructure, educate people on these situations and crises

Question 33

How to predict an earthquake?

Answer 33

Tremors can occur before earthquake, animal behavior can help predict it, instruments can record signs and help predict it in the future

Question 34

Active volcano definition

Answer 34

Volcano that still erupt (have erupted in the last 10000 years)

Question 35

Dormant volcano definition

Answer 35

Volcano that show no sign of activity, but are likely to erupt again

Question 36

Extinct volcano definition

Answer 36

Volcano that isn't expected to erupt again

Question 37

Features of a volcano

Answer 37

Magma chamber ----> pipe / fissures ----> Volcanic cone ----> crater ----> lava flows / rocks / lava bombs / gases

Question 38

What is a shield volcano

Answer 38

It has gaseous, runny, hot lava. It gives off few/no explosions (Kilauea)

Question 39

What is a cinder cone volcano

Answer 39

It has lots of glassy lava, ash and solid material. It is the simplest volcano with smallest cone and the steepest slope. (Monte Nuovo)

Question 40

What is a composite volcano (stratovolcano )

Answer 40

It ha slots of layers of ash and lava surrounding it and has fairly steep slopes. The eruptions are normally explosive (Mount Vesuvius)

Question 41

How do volcanoes affect people positively?

Answer 41

1. Some volcanoes areas become tourist attractions (income) 2. There could be diamonds in the volcanic pipes 3. Volcanic ash can act as a fertilizer in tropical regions and rocks can break down to form fertile soil 4. Hot springs are good for tourist attractions 5. Underground water in these areas is hot and good for generating heat or electricity

Question 42

How do volcanoes affect people negatively?

Answer 42

1. Water supply could be polluted 2. Ash and fumes in the air is dangerous for health 3. Buildings can collapse from the weight of the ash 4. Changes river systems / creates dams 5. Burns trees, house etc. 6. Ash blocks the sun 7. Ash and solidifying lava is dangerous 8. Planes cannot fly through ash

Question 43

How can you predict volcanic explosions?

Answer 43

Seismographs can be used to measure small earthquakes (These can trigger volcanic eruptions), ground temperatures will rise as the magma moves, gas and steam are given off before it erupts, the sides of the volcano swell and bulge which can be measured with a tiltmeter

Question 44

How can you be prepared for a volcano?

Answer 44

Set up a monitoring system or early warning system, make sure emergency and medical services are ready to evacuate, prepare and emergency plan, organize emergency supplies such as water or food

Question 45

Examples of the deadliest volcanic eruptions. (Know at least 2)

Answer 45

1. Mnt Vesuvius, Italy in 79AD, 3 360 casualties caused by pyroclastic flow 2. Laki, Iceland in 1783, 9 000 casualties caused by starvation 3. Kelut, Indonesia in 1586, 10 000 casualties 4. Uzen, Japan in 1792, 15 000 casualties caused by volcano collapse and tsunami 5. Nevada del Ruiz, Colambia in 1985, 25 000 casualties caused by mudflow 6. Mont Pelee, Martinique in 1902, 30 000 casualties caused by pyroclastic flow 7. Krakatau, Indonesia in 1833, 36 000 casualties caused by tsunami 8. Tambora, Indonesia in 1815, 92 000 casualties caused by starvation