Vocabulary
A rock that has been changed by heat, by pressure, or by both.
metamorphic rock
cast
What are some different ways that rocks can be used?
1. pieces of rocks are mixed into cement, which are used to build things.
2. rocks are mixed into asphalt, which are used to pave roads.
3. some rocks are used to build sculptures.
Which part of an animal's body is LESS LIKELY to become a fossil?
the skin
What is amber?
hardened tree sap, often a source of insect fossil
A process by which rocks are changed from one type into another.
rock cycle
a fossil created by a print or impression
imprint
Which statement about rocks is NOT true?
1. all rocks are made of minerals.
2. rocks come in different shapes, colors, and sizes.
3. a rock is always made up of just one kind of mineral.
4. scientists who study the physical properties of rocks are called geologists.
#3
What are the three properties used to identify minerals?
hardness, streak, and luster
What is an igneous rock?
"fire-made" rock formed from hot, molten rock material
The age of something compared with the age of another thing.
relative age
a naturally occurring substance that is neither plant nor animal
mineral
In what type of rock are most fossils found?
What happens when wood or bones become petrified?
The once-living parts are filled in by minerals
What are the three different types of fossils?
imprints, casts, and molds
hardened tree sap, often a source of insect fossils.
"fire-made" rock formed from hot, molten rock material
igneous rock
What causes a metamorphic rock to become an igneous rock?
melting, then cooling and hardening
What does finding fossil evergreen leaves tell scientists about an area?
the area was cool
Why are casts of fossils sometimes displayed in museums instead of the real fossils themselves?
1. Fossils are rare and valuable.
2. Some fossils are stored safely for further study.
3. Casts can be used to protect the fossils.
Rock formed when bits or layers of rocks are cemented together.
sedimentary rocks
a hollow fossil form clearly showing the outside features of the organism
mold
How are rocks with small grains and fine textures formed?
when lava cools quickly as it is exposed to air
What is conglomerate made of?
pebbles and large grains of sand cemented together
What is a rock cycle?
a process by which rocks are changed from one type into another