STRUCTURE OF THE EARTH

Question 1

earth layers

Answer 1

inner core, outer core, mantel (mesosphere, asthenosphere, lithosphere) , crust

Question 2

inner core

Answer 2

solid
iron and nickel

Question 3

outer core

Answer 3

iron, nickel and sulphur
* Liquid
* Magnetic field generation
o The liquid converts thermal and gravitational energy to magnetic energy  creating the magnetic field
* Polar wandering
o Pole changes over time
* Magnetic north south reversal
o Not regular, have changed hundreds of times over 250 Ma

Question 4

o Mantel

Answer 4

(less dense than core, Fe and Mg + silicate minerals (Si + O), silicate minerals), mafic rocks, low temp gradient = convection

Question 5

lower mantel

Answer 5

mesosphere
rigid

Question 6

 Asthenosphere

Answer 6

• Plastic
• At melting point

Question 7

 Uppermost mantel

Answer 7

Lithosphere)
* Rigid, floats on the asthenosphere
* Made of the upper mantel and crust
* Diamonds

Question 8

crust

Answer 8

 Oceanic or continental
 Granitic and basaltic)
 Felsic rocks

Question 9

temp and pressure profiles

Answer 9

 Increase as they go inwards
 Pressure is linear, temp is not

Question 10

body waves

Answer 10

primary - compression
secondary - shear, cannot travel through liquid

Question 11

seismology

Answer 11

o Study of vibration and waves within the earth
o Waves travel faster in stronger, dense materials

Question 12

waves effected by

Answer 12

rock density
phase of rock (solid/liquid)

Question 13

o Velocity increase with depth, boundaries marked by dramatic velocity changes and refraction of waves

Answer 13

 Greater velocity is more angled line
 Steeper line = less velocity

Question 14

o Mohorovivic discontinuity

Answer 14

crust mantle boundary)
 Waves reaching at different times after earthquakes, the denser material is faster = greater distance

Question 15

CMB

Answer 15

core mantel boundary
 S waves cannot travel through liquid
 How we know outer core is liquid

Question 16

wave travel

Answer 16

 Larger S wave shadow= larger core
 Waves travel with earths curvature

Question 17

why is interior hot

Answer 17

 Leftover heat from formation in solar system
 Radioactive decay of isotopes in the mantel