Types of Rocks
What type of rock forms from cooled lava or magma?
Igneous
What process is responsible for breaking down rocks into sediments?
Erosion
What are rocks made of?
Minerals
What is a common sedimentary rock formed from calcium carbonate?
Limestone
What type of metamorphic rock has a layered or banded appearance?
Foliated
What type of rock forms from the remains of living organisms?
Organic sedimentary
What two processes turn sediments into sedimentary rock?
Compaction and cementation
What type of igneous rock forms when magma cools quickly at the surface?
Extrusive
What are rock fragments in sedimentary rocks called?
Clasts
What happens to the size of crystals in a metamorphic rock when the pressure increases?
They become larger
Which type of igneous rock forms underground from slowly cooled magma?
Intrusive
What process turns igneous rock into magma?
Melting
What type of igneous rock is glassy and forms when lava cools very quickly without crystal growth?
Obsidian
What is the most common type of sedimentary rock that contains fossils?
shale
What is the term for the alignment of minerals in metamorphic rocks?
Foliation
What type of rock is formed when heat and pressure change an existing rock?
Metamorphic
What two factors are responsible for the formation of metamorphic rocks?
Heat and Pressure
Why does obsidian have a glassy texture?
It forms from quickly cooled lava.
What type of sedimentary rock forms from dissolved minerals?
Chemical sedimentary rock
What type of rock is formed when shale is exposed to heat and pressure?
Slate
Which volcanic rock is so light it can float in water?
Pumice
What must happen for a sedimentary rock to become an igneous rock?
It must melt into magma, then solidify.
Why does pumice have holes and a spongy texture?
Gas bubbles escape as the rock cools
How can a sedimentary rock become a metamorphic rock?
Heat and Pressure
How does a metamorphic rock become an igneous rock without becoming sedimentary?
It must melt into magma and then solidify