Inside the earth

Question 1

what is inside the earth?

Answer 1

• earth’s interior is hot and under enormous pressure.
• Temperature of Earth’s interior increases with depth
• Called the geothermal gradient

Radioactivity and friction created and continue to create hot Earth interior

Question 2

seismic wave:

Answer 2

energy released by earthquakes that travels through Earth’s interior.

• Most of what is known of Earth’s deep interior comes from analysis of behavior of seismic waves

Earthquake: sudden shaking of the ground caused by movements of Earth’s crust

Question 3

earths inner structure

Answer 3

crust
↓
lithosphere
↓
asthenosphere
↓
lower mantle
↓
outer core
↓
inner core
↓
earths centre

Question 4

inner core:

Answer 4

composed of solid iron and nickel

-Extends from Earth’s center to about 5,150 km below Earth’s surface

Question 5

outer core:

Answer 5

composed of liquid iron and nickel

• Extends to about 2,900 km below Earth’s surface

Question 6

magnetic field

Answer 6

• created from circulating liquid metal in outer core generates electrical currents.

Magnetic field forms..
magnetosphere: shields Earth from solar wind (stream of electrically charged particles emitted by Sun).

Magnetic North Pole—found where the magnetic field enters the planet

The geographic North Pole (true north)—found at Earth’s axis of rotation

Question 7

lower mantle:

Answer 7

he layer of heated and slowly deforming solid rock that lies between the base of the crust and the outer core

-Lies 2,900 km below the surface and extends upward to approximately 200 km below the surface

Question 8

Asthenosphere:

Answer 8

found between depths of 100 and 200 km Softer and weaker than the lower mantle beneath

Question 9

lithosphere

Answer 9

the crust and the lithospheric mantle beneath it, extending to a depth of about 100 km (62 mi) on average

Question 10

the 2 types of crust:

Answer 10

Continental crust: makes up continents, composed mainly of granite
- Granite: a silica-rich rock made up of coarse
grains

Oceanic crust: beneath the oceans, composed mainly of basalt
- Basalt: a dark, heavy, fine-grained volcanic
rock

Question 11

magma:

Answer 11

MELTED rock that is BELOW the surface of the crust. Often hardens into granite

Question 12

lava:

Answer 12

is magma that spills onto the surface of Earth’s crust.
(Molten rock that solidifies when it comes to the surface)

Often hardens into basalt

Question 13

Moho:

Answer 13

boundary that separates crust from lithospheric mantle; lies about 35 km deep on average
Deepest beneath high mountains and shallowest beneath the oceans
Overall, thickness of Earth’s crust is 0.01% to 1% of radius of planet (about same as thickness of an apple peel as a % of rest of the apple)

Question 14

The Kola superdeep borehole

Answer 14

soviet project aiming to drill deep into the crust.

• reached depth of 12,262 m