GEOL20E Review

Question 1

We know the outer core is liquid because of...

Accepted Answer

The behavior of primary (compressional) seismic waves., The bulk composition of the Earth, inferred by chondrites., The behavior of secondary (shear) seismic waves., The total mass of the Earth, inferred by its orbit around the sun.

Question 2

Why is there liquid mantle rock below Hawai&#x27;i?

Accepted Answer

As islands move away, pressure release lowers the mantle&#x27;s melting point, Very high pressure at the convergent boundary creates a chain of hot spots, A hot plume from the deep mantle raises the temperature of the upper mantle, Water from the oceanic crust lowers the mantle&#x27;s melting point

Question 3

Ocean trenches are usually found near volcanic chains. These volcanic chains get their magma from

Accepted Answer

Flux melting, Decompression melting

Question 4

We know the outer core is liquid because of...

Accepted Answer

The behavior of secondary (shear) seismic waves.

Question 5

The mantle is mostly solid and ultramafic.

Accepted Answer

True

Question 6

Which of the following commonly occurs at subduction zones?

Accepted Answer

Deep, powerful earthquakes in a region parallel to the subducted slab.

Question 7

The mantle melts at mid-ocean ridges because of decompression

Accepted Answer

True

Question 8

Why is there liquid mantle rock below Hawai&#x27;i?

Accepted Answer

A hot plume from the deep mantle raises the temperature of the upper mantle

Question 9

Which of the following commonly occurs at subduction zones?

Accepted Answer

Two oceanic plates "crumple" as they collide, forming mountains., Volatiles from the subducted slab lower the surrounding mantle pressure., Mantle plumes rise toward the surface, creating volcanoes and earthquakes., Deep, powerful earthquakes in a region parallel to the subducted slab.

Question 10

Ocean trenches are usually found near volcanic chains. These volcanic chains get their magma from

Accepted Answer

Flux melting

Question 11

The mantle melts at mid-ocean ridges because of decompression

Accepted Answer

True, False

Question 12

The crust-mantle boundary (Moho) is shallower under continents than oceans due to lower continental density.

Accepted Answer

False, True

Question 13

Melting the mantle almost always requires increasing its temperature.

Accepted Answer

True, False

Question 14

The crust-mantle boundary (Moho) is shallower under continents than oceans due to lower continental density.

Accepted Answer

False

Question 15

Oceanic crust covers more of Earth&#x27;s surface today than it did billions of years ago.

Accepted Answer

False

Question 16

Melting the mantle almost always requires increasing its temperature.

Accepted Answer

False

Question 17

Oceanic crust covers more of Earth&#x27;s surface today than it did billions of years ago.

Accepted Answer

False, True

GEOL20E Review

Questions 17

GEOL20E Review

Questions 17