SCIENCE Third Grade Week Three

Which rocks are formed from melted and cooled magma or lava and often look glassy?

igneous rocks

Which rocks are made up of pieces of rocks, animal shells, or plant remains that have been pressed together?

sedimentary rocks Examples – sandstone and limestone

Which rock was once another type of rock that was changed by heat and pressure?

metamorphic rock Examples – marble and slate

What type of soil is made of decayed parts of once-living organisms and is dark, soft, and crumbly?

humus

What type of soil is gritty with large grains and lets water leave it quickly?

sand

The four basic materials that soil can be made from are humus, sand, clay and ______.

silt

Minerals are earth materials that were formed in nature, have never been alive, and can be identified by their_______.

properties

Which property of minerals is usually discovered by a scratch test?

hardness

Color is a property that helps scientists identify minerals. Why should you not use only color when identifying a mineral?

Many minerals have the same color.

What property identifies the mineral as shiny, pearly, glassy, or dull?

luster

What are some other properties that scientist can use to identify minerals?

reacts to an acid by bubbling splits into thin sheets magnetic

What are rocks that have been formed from remains of living things that lived long ago?

fossils

What type of fossil has an opening that is the shape or imprint of something that was once a living thing?

mold

What type of fossil was formed when sediments filled a mold fossil and harden making a fossil that looks like something that used to be living?

cast

Why can you only find imprint fossils of leaves and feathers and can never find the actual leaves and feathers?

The actual leaves and animal parts rotted away long ago.

How would scientists know that the Sand Hills of South Carolina were once covered with the ocean?

They have found fossils of sharks’ teeth and shells.

Where are most glaciers found?

They are found where temperatures are very cold such as in high mountains or near the poles.

What do you call the flat top of a mountain?

plateau

What is the difference in valleys and canyons?

Valleys are lowland areas between mountains. Canyons are deeper valleys with steep sides.

What are three uses of our earth’s resources?

for fuels for building for growing plants

What is the difference in weathering and erosion?

Weathering causes earth materials to break apart, but erosion causes earth materials to wash away.

What is called it called when eroded materials are move to a new location?

deposition

What happens in a landslide?

Rock, sand, or soil move rapidly to a lower location.