Plate Tectonics Lecture A-C

Question 1

What crust is used for countertops?

Answer 1

Continental crust, Consists of granite, pink-colored rock

Question 2

What crust forms from volcanoes?

Answer 2

BASALT, oceanic crust consists of basalt forms from volcanoes and lava flows

Question 3

What does Earth’s Mantle consist of?

Answer 3

Olivine, makes up Hawaii’s green sandy beaches

Question 4

Solid inner core and liquid outer core consist of what?

Answer 4

IRON

Question 5

What creates Earth’s magnetic field?

Answer 5

LIQUID OUTER CORE, turning earth into an electro magnet

Question 6

Continental Drift Theory

Answer 6

The idea that continents were once together

ALFRED WEGENER (German Meteorologist) AND HARRY HESS (US Navy Captain)

Question 7

Alfred Wegener Summary of continental drift

Answer 7

1) Puzzle Pieces fit of the continents
2) Matching rocks across coninents
3) Mountain Ranges that line up when the continents are reassembled
4) Glacial features that line up when the conitnents are reassembled
5) Similar land-based fossils found on many different continents

Question 8

Harry Hess, Mechanism for Continental drift

Answer 8

Seafloor AGES YOUNGEST NEAR RIDGES and OLDEST AWASY FROM RIDGES

1) Underwater mountain ranges
2) Pillow Basalts that indicate an underwater origin for oceanic crust
3) Seafloor is youngest near Midocean ridges
4) Magnetic reversals match across ridges

Question 9

Normal polarity vs Reverse polarity

Answer 9

Field Points TOWARD NORTH (Normal)

Field points TOWARD SOUTH (Reverse)

Question 10

SEAFLOOR SPREADING

Answer 10

Magnetic reversals indicate that the Earth is being torn apart along these ridges

Question 11

Plates and plate boundaries

Answer 11

PLATES : Large stable areas with no Earthquake activity

Plate Boundaries : Spaces Between these plates

Question 12

Lithosphere and Asthenosphere

Answer 12

Lithosphere : Rigid plate (Crust and Cold uppermost mantle is part of lithosphere)

Asthenosphere : Deformable surface that the rigid plate rides on (Rest of mantle) CAPABLE OF FLOW

Question 13

Convection within the asthenosphere

Answer 13

WHAT DRIVES MOVEMENT OF EARTH’S PLATES, Convection circular style of mixing

ALSO HOW EARTH CIRCULATES HEAT

Question 14

MID OCEAN RIDGES

Answer 14

FORM AT DIVERGENT BOUNDARIES BETWEEN TWO oceanic plates

Question 15

RIFT VALLEY with mid-ocean ridge

Answer 15

The mid-ocean ridge that splits the Atlantic Ocean cuts right through Iceland forming a rift valley

Question 16

RIFT VALLEYS

Answer 16

Commonly form at divergent boundary between two continental plates

WILL eventually fill with oceanic crust and ocean water as the continents split apart

Question 17

SUBDUCTION

Answer 17

Convergent Boundaries with OCEANIC LITHOSPHERE ONE PLATE IS SUBMERGED BENEATH THE OTHER

Question 18

Thickness of Continental lithosphere and oceanic lithosphere

Answer 18

Continental lithosphere is THICK LIKE A CRUISE SHIP

Oceanic lithosphere is THIN LIKE A CANOE

Oceanic lithosphere is submerged from Continental

Question 19

Magma (Formulation)

Answer 19

Mantle Rock + H20 = Magma

MANTLE ROCK IS NOT MOLTEN

Question 20

How Magma is generated

Answer 20

Water from wet seafloor being subducted gets evaporated and the water causes mantle to melt to create magma

Question 21

CONTINTEAL VOLCANOES

Answer 21

Form at convergent boundaries as an oceanic plate is subducted below a continent

It makes up the Andes Mountains

Question 22

VOLCANIC ISLANDS

Answer 22

Oceanic Plate is subducted below another oceanic plate

Volcanoes grow from the seafloor to sea level

INDONESIA, PHILIPPINES, JAPAN, AND NEW ZEALAND

all volcanic islands from subduction

Question 23

LARGE MOUNTAINS

Answer 23

Form where two continental plates collide at a convergent boundary

Himalayan Mountains formed from the collision of India and Asia

Question 24

San Andreas Fault

Answer 24

Transform Boundary

Question 25

SALTON SEA

Answer 25

Results in the sourthern San Andreas that forms a Pull apart basin

Question 26

SAN GABRIEL MOUNTAINS

Answer 26

Being pushed up due to compression along San Andreas Big Bend

Question 27

North American Plate what plate boundaries does it contain?

Answer 27

ALL PLATE BOUNDARIES

Convergent, Transform, and Divergent