Chapter 9 Vocabulary

Question 1

Earthquakes

Answer 1

The vibrations in the ground that result from movement along breaks in Earths lithosphere

Question 2

Fault

Answer 2

A break in Earth’s lithosphere where one block of rock moves toward, away from, or past another

Question 3

Seismic Waves

Answer 3

Energy that travels as vibrations on and in Earth

Question 4

Focus

Answer 4

Waves that originate where rocks first move along the fault, at a location inside Earth called Focus

Question 5

Epicenter

Answer 5

The location on Earth’s surface directly above the earthquake’s focus

Question 6

Primary waves

Answer 6

Causes particles in the ground to move in a push-pull motion similar to a coiled spring

Question 7

Secondary Waves

Answer 7

Causes particles to move up and down at right angles relative to the direction the wave travels

Question 8

Surface Waves

Answer 8

Causes particles in the ground to move up and down in a rolling motion

Question 9

Seismologists

Answer 9

Scientists that study earthquakes

Question 10

Seismometer

Answer 10

Measures and records ground motion and can be used to determine the distance seismic waves travel

Question 11

Seismograph

Answer 11

Graphical illustration of seismic waves

Question 12

Volcano

Answer 12

A vent in Earth’s crust through which melted-or molten- rock flows

Question 13

Magma

Answer 13

Molten rock below Earth’s surface

Question 14

Lava

Answer 14

Molten rock that erupts onto Earth’s surface

Question 15

Hot Spot

Answer 15

Volcanoes that are not associated with plate boundaries

Question 16

Shield Volcano

Answer 16

Common volcanoes along the divergent plate boundaries and oceanic hot spots; they are large with gentle slopes of basaltic lava

Question 17

Composite Volacano

Answer 17

Large, steep-sided volcanoes that result from explosive eruptions andesite and rhyolitic lava and ash along convergent plate boundaries

Question 18

Cinder Cone

Answer 18

Small, steep-sided volcanoes that erupt gas-rich, basaltic lavas

Question 19

Volcanic Ash

Answer 19

Tiny particles of pulverized volcanic rock and gas

Question 20

Viscosity

Answer 20

A liquid’s resistance to flow