Chapter 12 - Forces in the Earth - 6th grade

Normal Fault

• Break in the crust in which the over hanging block of rock has slid down.

• A type of fault where the hanging wall moves up relative to the footwall.

• A fracture in the Earth's crust where two blocks slide past each other horizontally.

• A geological formation where rocks are pushed together and fold.

Sea-floor spreading

• Theory that the ocean floor spreads apart as new crust is formed at mid-ocean ridges

• Process by which tectonic plates collide and create mountains

• Concept that oceanic crust is older than continental crust

• Theory that the ocean floor remains static over time

Focus

• Point inside the earth where rock first moves, starting an earthquake

• The surface location directly above the earthquake's origin

• The area where seismic waves are first detected

• A measure of the earthquake's intensity

Volcano

• Mountain that develops where magma pushes up through the earth's surface

• A type of cloud formation

• A large body of water

• A geological fault line

Continental Drift

• Theory that the major landmasses of the earth move

• A hypothesis that continents are fixed in place

• A model explaining ocean currents

• A concept related to climate change

Convection Current

• Circular motion of a gas or liquid as it heats

• A process of heat transfer through direct contact

• The movement of air caused by temperature differences

• A type of wave motion in fluids

What is the difference between the focus and epicenter of an earthquake?

• Focus: point on the earth's SURFACE directly over the epicenter

• Epicenter: point INSIDE the earth where rock first moves

• Focus: point INSIDE the earth where rock first moves

• Epicenter: point in the atmosphere where seismic waves are first detected

Strike-slip Fault

• Break in the crust in which the blocks of rock move horizontally past each other

• A type of fault where rocks move vertically

• A geological formation caused by volcanic activity

• A fracture in the Earth's crust that does not result in movement

Fault

• Break in the earth's crust along which movement occurs

• Type of rock formation that is solid and unyielding

• Natural disaster caused by seismic waves

• Layer of soil that supports plant life

Name 3 types of volcanoes

• Cinder Cone Volcano

• Shield Volcano

• Composite Volcano

• Lava Dome Volcano