quit unit 2

Question 1

layers of the eart deepest to outer

Answer 1

core
mantle
lithosphere
crust

Question 2

core

Answer 2

most dense
made of nickle and iron
solid inner core, liquid outer core

Question 3

mantle

Answer 3

where convection occurs
hot, semi-solid rock influences, tectonic activity
asthenosphere

Question 4

crust

Answer 4

5 km thick below the ocean
70 km thick below the continents
lithosphere

Question 5

continental

Answer 5

forms all land masses
older, thicker, and less dense
Granite- 2.7g/cm3

Question 6

oceanic

Answer 6

under oceans
younger, thinner, and more dense
Basalt- 2.9 g/cm3

Question 7

theory of continental drift

Answer 7

alfred wegener, 1912
continents have been moving around
and single continent pangea broke up 175-200 million years ago

Question 8

theory of plate tectonics

Answer 8

explains how and why the continents move
heat from core causes uneven heating and convention occurs within the mantle

as these currents move magma the plates above collide seperate and slide
crust is destroyed and created reforming earths surface

Question 9

what provides evidence for the theory of plate tectonics

Answer 9

mid atlantic ridge and seafloor of atlantic ocean

Question 9

mariana trench

Answer 9

deepest trench on earth
indo australian and pacific plates colliding

deepest point is challenger deep

Question 9

mid ocean ridge

Answer 9

run direct down center of atlantic
rocks at equal distance from ridge same age
sediment builds up gets thicker the further from the ridge
seismic activity is frequent
paleomagnetic stripes match both sides

Question 10

hot spot theory

Answer 10

magma plumes rise and break through the crust at host spots
creates volcanoes farfrom plate boundaries (hawaii)
hot spots stay in one place but the plate moves over top of it which creates line of volcanoes

Question 11

earthquakes

Answer 11

when plates stuck together and dont move for a long time so
pressure builds
burst of energy releases when movment occurs energy released moves as seismic waves through lithosphere

Question 12

tsunamis

Answer 12

caused by sudden release of energy on the seafloor(earthquake/volcanic eruption)
energy displaces a large volume of water and moves quickly through deep water
as approaches shallow coast line waves slow and build height

Question 13

hydrothermal vents

Answer 13

cracks in crust along plate boundaries and water seeps down

gets heated by mantle and dissolves mineral by surrounding rocks
pressure forces water back up
as superheated mineral rick water meets cold deep water it rapidly cools and the minerals recrystalized and build vent structure
creates small plume of water in cold sea ecosysten formed here

Question 14

oldest seafloor

Answer 14

deepeat part of trench

Question 15

continental shelf

Answer 15

shallow waters
continental crust emerged
makes up 8 percent of ocean
biologically richest

Question 16

continental slope

Answer 16

begins at shelf break and extends to abyssal plain

Question 17

deep seafloor

Answer 17

abyssal plain
mostly flat
hills, plateaus, other features

Question 18

what is the core made of