Igneous Rocks

Question 1

How much does igneous rocks cover Earth’s surface?

Answer 1

5%

Question 2

How much does igneous rocks make up of the Earth’s crust?

Answer 2

95%

Question 3

How do igneous rocks form?

Answer 3

From cooling and solidification of lava and magma

Question 4

What’s the range of temperature igneous rocks are formed?

Answer 4

600- 1300 degrees celcius

Question 5

What are plate tectonics?

Answer 5

Large-scale movements and interactions between the Earth’s plates

Question 6

How do you classify igneous rocks?

Answer 6

By texture and composition

Question 7

What are the 2 types of igneous textures?

Answer 7

Extrusive and intrusive

Question 8

What’s extrusive texture?

Answer 8

Lava

Question 9

What’s intrusive texture?

Answer 9

magma

Question 10

What’s the speed of cooling and crystal size of extrusive igneous rocks?

Answer 10

Fast and fine

Question 11

What’s the speed of cooling and crystal size of intrusive igneous rocks?

Answer 11

Below the crust: Medium and medium

Deep under ground: Slow and large

Question 12

What’s a dike?

Answer 12

A vertical rock between older layers of rock

Question 13

What’s a sill

Answer 13

A tabular (parallel) sheet intrusion that has intruded between older rocks of foliation

Question 14

What’s pluton?

Answer 14

A body of intrusive igneous rock that’s crystallized from magma slowly cooking

Question 15

What’s laccolith?

Answer 15

A sheet intrusion that has been injected between 2 layers of sedimentary rocks

Question 16

What are the 3 products extrusive volcanic activity produce?

Answer 16

Lava, pyroclastic debris, and gases

Question 17

What’s pyroclastic debris?

Answer 17

Fire fragments, ash, tephra, cinders

Question 18

Which eruptions form composite of strato-volcanoes?

Answer 18

Felsic & intermediate

Question 19

What does the term composite refer to when talking about volcanoes?

Answer 19

Alternating types of layers

Question 20

How do composite or strato-volcanoes form?

Answer 20

From alternating eruptions of lava and explosive ash clouds

Question 21

What are the main features of a volcano?

Answer 21

Ash cloud, pyroclastic flow, crater, main vent, lava flow, magma chamber, secondary vent, secondary cone, and volcanic bombs

Question 22

What are the typical conical volcanoes?

Answer 22

strato-cones or composite volcanoes

Question 23

What is a caldera?

Answer 23

A collapsed strato-volcano

Question 24

What happens when a strato-volcano collapse?

Answer 24

The magma chamber empties

Question 25

What produces cinder cones?

Answer 25

Eruptions with little lava and much gas

Question 26

What’s a cinder cone volcano?

Answer 26

A volcano built from blobs of lava ejected from a single vent

Question 27

What’s a stratovolcano?

Answer 27

A volcano built of layers of lava, ash, and volcanic debris

Question 28

What’s a shield volcano?

Answer 28

A volcano build from countless outpourings of fluid lava flows

Question 29

What’s a batholith?

Answer 29

An intrusive igneous body greater than 40 sq. miles in area

Question 30

What is a hotspot?

Answer 30

A portion of the Earth’s surface which experiences volcanism and where lava pushes up from under the mantle and creates volcanoes

Question 31

What are the two well-known hotspots in the U.S.?

Answer 31

Hawaii and Yellowstone