When stuck rocks underground suddenly slip, what travels outward?

• Sunlight shining through the layers of buried rock
• Air carrying sound through an empty underground tunnel
• Energy that shakes the surrounding ground

What rock movement can start an earthquake?

• Sunlight slowly warming rocks on a hillside
• Underground rocks suddenly slipping or breaking
• Ocean waves washing loose stones onto a beach

Shaking can reach places away from where rocks suddenly moved underground.

Circle one:   True   False

Rocks slip underground. Their energy reaches Jay's classroom and the floor shakes. Which part is an effect felt at the surface?

• The rocks sticking before the sudden slip
• The rocks storing energy before they move
• The classroom floor shaking under Jay

Rocks suddenly slip along an old underground crack. No new crack forms. What can this slip start?

• Only a slow change with no shaking
• An earthquake that sends shaking outward
• Only a crack that must reach the surface

Rocks can store energy while they are stuck, before they suddenly slip.

Circle one:   True   False

One earthquake shakes a nearby town strongly and a farther town lightly. Which explanation could account for the difference?

• The farther town's people must have imagined shaking
• Shaking can weaken as it travels through the ground
• Every town receives exactly the same amount of shaking

Zara says, "My house shaking made the rocks underground slip." Which explanation matches the lesson?

• The rocks slipped and sent shaking to her house
• Her house shook and pushed the buried rocks apart
• The rocks could only slip after everyone felt shaking