Melting of Rocks and Plutons

Question 1

In order for a volcanic eruption to occur you have to have some sort of ______ rocks

Answer 1

melted/molten

Question 2

rocks generally melt between ____ and ____ degrees celsius

Answer 2

800, 1200

Question 3

to under stand volcanism and volcanic eruption, you must understand…

Answer 3

how rock melts

Question 4

crustal temperature increases with…

Answer 4

depth

Question 5

Lower pressure promotes ______

Answer 5

melting

Question 6

what does lower pressure cause?

Answer 6

a lower melting point in rocks

Question 7

Rocks melt at lower temperatures if the pressure is ______

Answer 7

lower

Question 8

If the pressure increases you need to reach _____ temperatures in order for the rock to melt

Answer 8

higher

Question 9

Any presence of ______ in a rock lowers melting point

Answer 9

moisture

Question 10

what does the presence of moisture do to a rock?

Answer 10

lowers its melting point

Question 11

rocks melt when…

Answer 11

• temperature increases
• pressure decreases
• water is added to the rock

Question 12

what are plutons?

Answer 12

magma that never reaches the surface

Question 13

what are five types of plutons?

Answer 13

batholiths, stocks, dikes, sills, and volcanic necks

Question 14

how can a pluton reach the surface?

Answer 14

after it cools and becomes igneous rock, the layers above may become eroded away, exposing the plutons

Question 15

which is the largest pluton?

Answer 15

a batholith

Question 16

what are dikes and sills?

Answer 16

thin layers of plutons

Question 17

what is the difference between a dike and a sill?

Answer 17

a dike cuts across existing layers, and a sill squeezes in parallel

Question 18

what is a volcanic neck?

Answer 18

a volcano that never erupted

Question 19

is this a dike or sill?

Answer 19

dike

Question 20

Is this a dike or sill?

Answer 20

sill