Structure of Earth's Interior

Question 1

What are the layers of the earth (detailed)

Answer 1

Crust->Upper mantle->mantle transition->Lower mantle->Outer core->core transition->inner core

Question 2

Oceanic crust characteristics

Answer 2

Oceanic crust floats lower than continental crust because it is thinner and denser. This is why oceans are above oceanic crust

Question 3

Seismogram

Answer 3

A seismogram is a recording of the ground motions at a particular location
due to the passage of seismic waves generated by an earthquake

Question 4

Components of a seismograph

Answer 4

seismometer, amplifier, clock, and recorder (or

telemetry)

Question 5

What was the earliest seismometer?

Answer 5

A model of the “earthquake weatherclock “invented in
132 A.D. by the Chinese astronomer and mathematician Chang Heng. Eight dragons held bronze balls in their mouths. An internal mechanism, activated by even a slight tremor, opened the mouth of one dragon, releasing the ball to sound an alarm as it clanked into the open mouth of a metal toad below.

Question 6

What is the suspended mass on a seismometer called?

Answer 6

The Inertial mass. This mass tends to remain stationary when the ground is shaking

Question 7

Continental Crust characteristics

Answer 7

variable thickness 20-50 km, silicic composition (lots of SiO2)

Question 8

Oceanic crust Characteristics

Answer 8

uniform thickness 10 km, basaltic/mafic composition (not much SiO2)

Question 9

Boundary between crust and mantle

Answer 9

Boundary between crust and mantle called Moho–vP, vS, and ρ all increase across the Moho.

Question 10

Isostasy

Answer 10

crust is in floating equilibrium on the denser mantle below

Question 11

Mantle Composition

Answer 11

Composition = ultramafic rocks, mainly olivine (Mg,Fe)2

SiO4 and pyroxene (Mg,Fe) SiO3

Question 12

Core Composition

Answer 12

Composition = Iron + Nickel + a bit of Sulfur.

Outer Core is liquid–doesn’t transmit shear waves