Interior Processes

Question 1

What is an anticline?

Answer 1

An upfold in rock layers

Question 2

What is a syncline?

Answer 2

A downfold in rock layers

Question 3

How do dome mountains form?

Answer 3

Rock layers get pushed up and dome is formed

Question 4

Describe a Plutonic Dome mountain and age of layers

Answer 4

Igneous intrusion pushes up rock layers and sedimentary layers wear away leaving igneous rocks at top.
Top layer is younger

Question 5

Describe a Tectonic Dome mountain and age of layers

Answer 5

Uplifting force pushes up rock layer

Top layer is older

Question 6

What are plate tectonics?

Answer 6

A theory that the surface of the Earth is in giant pieces or lithospheric plates and the movement, interactions and formation of these plates

Question 7

What is the Elastic Rebound Theory?

Answer 7

Friction prevents 2 plates from moving, strain becomes too great and plates suddenly move. Cause of Earthquake

Question 8

What is a shadow zone and what does it indicate?

Answer 8

Area with no p-waves or s-waves from an Earthquake. Occurs because p-waves get refracted and s-waves can’t transmit through liquid.
Indicates that outer core is liquid because outer core is up to 2900km below surface and peed of p-waves increase at 5200km
Also that the inner core must be solid

Question 9

What is a fault?

Answer 9

Breaks in lithosphere where movement has occurred. Have footwalls and hanging walls

Question 10

Describe the 3 major types of faults

Answer 10

Normal: Hanging wall slides down as tension pulls crust apart
Reverse: Hanging wall slides up as compression occurs
Strike-Slip: Hanging wall moves horizontally as it slides past footwall (San Andreas fault)

Question 11

What are folds?

Answer 11

Occur deep below surface, sometimes exposed due to uplift, weathering and erosion. Main types are anticline and syncline

Question 12

How does magma form at subduction boundaries?

Answer 12

Water in the subducted rock is released into the athensophere, then the water lowers melting temperatures of materials in the athensophere, leading to the formation of magma.

Question 13

What is Liquefaction?

Answer 13

Process where sediment/soil acts like a liquid causing buildings to sink

Question 14

What are the three types of magma and explain their characteristics. (I.e Content and where they are found)

Answer 14

Basaltic: 50% silica, low gas, low viscosity, high melting temp, rarely explosive. Found in rift and hot spots
Andesitic: 60% silica, medium gas, medium viscosity, medium melting temp, sometimes explosive. Found in subduction boundariess
Rhyolitic: 70% silica, high gas, high viscosity, low melting temp, usually explosive. Found in continental hot spots

Question 15

Explain Earthquake body waves and the two types

Answer 15

Body Waves: Waves of energy which travel from focus of an earthquake.
P-waves (Primary Waves):
Compression a.k.a longitudinal waves
Vibrate parallel to direction in which the wave is travelling
S-Waves (Secondary Waves):
Shear waves a.k.a Transverse waves
Vibrate perpendicular to direction that the wave is travelling

Question 16

What are the differences and similarities between p-waves and s-waves

Answer 16

P-waves travel 2x faster than s-waves

Both travel faster in denser materials

Question 17

Explain Earthquake surface waves and the two types and which travels faster

Answer 17

Surface Waves: Waves that travel along the surface of Earth
Love Waves: Side - side movement a.k.a surface transverse waves
Rayleigh Waves: Travel in elliptical patterns a.k.a torsional vibrations
Love waves travel faster than Rayleigh waves

Question 18

Describe the Divergent plate boundary

Answer 18

Plates diverge (move away) from each other
Usually along ocean floors and produce rift valleys
Rift valleys have fracture zones which are perpendicular to ridge
Earthquakes occur at fracture zones

Question 19

Describe the Convergent plate boundary

Answer 19

Plates converge (move towards) each other. 2 types
Subduction: One plate goes under the other
Collision: Plates hit each other head on

Question 20

Describe the Transform plate boundary

Answer 20

Plates slide by each other. Ex: San andreas fault

Question 21

What is a Richter scale?

Answer 21

Used to express strength/magnitude of Earthquake

Question 22

What contributes to continental growth?

Answer 22

Deep-sea Sediments: Scraped off sediments as oceanic plate submerges under continental
Igneous Rock: From cooled magma builds up surface of continents
Sediments: Deposited by rivers, helps build up edges
Terrane: Large piece of litho. plate displaced over a large area

Question 23

Describe the 3 chars. of a Terraine

Answer 23

Must be bound on all 3 sides by faults
Fossils must be completely different than neighbouring fossils in area
Different magnetic record, compared to that around it

Question 24

What is the Mohorovicic Discontinuity?

Answer 24

Change in velocity of p-waves and s-waves at boundary between crust and mantle

Question 25

What is the Transition Zone?

Answer 25

At depths between 400 and 670 km, seismic wave velocity significantly increase. Located in middle of the mante

Question 26

Explain Wegner’s continental drift hypothesis and it’s strengths and weaknesses

Answer 26

The theory that overtime continents drift from one location to another

Question 27

What were the proofs to Wegner’s continental drift hypothesis?

Answer 27

Coastlines seem to fit
Fossil remains of mesosaurus were only found near the east coaast of S.A and west coast of Africa
Unique rock formation on S.A and Africa which match up
Climate change evidence consistent with Africa and S.A

Question 28

What were the disadvantages to Wegner’s continental drift hypothesis?

Answer 28

Does not explain how continents move

Suggested plates move 100 times the speed of what they actually move

Question 29

What are the 3 causes of plate movement?

Very long answer

Answer 29

Mantle Convection: Heat transfer process which heat from core goes through mantle. Convection cells form in the middle
Slab Pull: Force at subduction boundary. Subducting part of litho. plate exerts pull on rest of plate
Ridge Push: At ridges hot magma rises and heats rocks near it and the rocks expand and become elevated above sea-floor. This produces downward slope away from ridge and older rocks cool, become denser and slide down slope. The rising magma forms new rocks at M.O.R and denser litho, slides away

Question 30

What is stress and explain the 3 main types

Answer 30

Stress: Internal resistance of an object to a force that strains that particular body
Compression: Rock layers are squeezed inwards and layers become thicker and shorter
Tension: Rock layers are stretched outwards and layers become thinner and longer (Thinner layers are weaker and can fracture)
Shear: Rock layers slide past each other. Can change shapes of rocks

Question 31

Explain the 3 types of lava flows

Answer 31

High temp. basaltic lava: flows quickly out of vents and forms pahoehoe. Has smooth rope-like surfaces
Low temp. basaltic lava: Moves slower, cools quickly, forms aa, has sharp jagged surfaces
Pillow Lava: Forms underwater, has pillow like-shapes, if pressure builds up inside it cracks

Question 32

What are the 3 major types of Volcanoes and explain each

Answer 32

Cinder Cones: Smallest and have oval base. Usually form in groups near large volcanoes. Cone forms from equption of lava
Composite: Formed from repeated explosive eruptions as material accumulates around vent. Hot ash can mix with snow and ice to form fast moving mudslides (lahar)
Shield: Largest with fast flowing basaltic lava. tend to be less explosive

Question 33

How does a Caldera lake form?

Answer 33

Volcano erupts and partly empties magma chamber
Top of volcano collapses in
Rainwater fills caldera