What is igneous rock that forms from lava that erupts onto Earth's surface called?
Extrusive Rock
100
Where do most metamorphic rocks form?
Deep underground.
100
__________ is the process that presses sediment together.
Compaction
100
The look and feel of the rock's surface is its ________.
Texture
100
What kind of reef forms on top of a volcanic island far from land?
An atoll.
200
What is the most abundant intrusive rock?
Granite
200
What three things can change an existing rock into a metamorphic rock?
heat, pressure, and chemical reactions
200
What are the three types of sedimentary rocks?
Clastic Rocks, Organic Rocks, and Chemical Rocks
200
If a rock has large and easy to see grains it is considered to have what kind of texture?
Coarse-grained
200
Over time, coral buried by sediments can turn into what?
Limestone
300
Name three uses of igneous rocks.
tools, building materials (granite), statues (granite), gravel (basalt)
300
How do geologists classify metamorphic rocks?
According to the arrangement of the grains that make up the rock.
300
What are the four steps that turn rock into sedimentary rock?
Erosion, Deposition, Compaction, Cementation.
300
What do geologists observe when studying a rock sample?
The rock's color, texture, and it's mineral composition.
300
Coral reefs are made up of a material that forms the skeletons of coral animals. What is this material?
calcite
400
An igneous rock that cools in two stages - a slow stage forming large crystals and then a faster stage forming very small crystals - has what kind of texture?
A prophyritic texture.
400
The heat that changes a rock into a metamorphic rock comes from where?
Friction of plate movement or the heat of the mantle.
400
Chalk formed from sediments made of skeletons of microscopic living things in the ocean is what type of sedimentary rock?
Organic Rock
400
How did the rock cool if it has no visible grain and is very smooth and shiny.
It cooled very quickly.
400
What happens to a coral reef if the sea level rises or if the sea floor sinks?
It will die.
500
What three ways are igneous rocks classified?
Igneous rocks are classified according to the origin, texture, and mineral composition.
500
What type of texture will a metamorphic rock have if it cannot be split into layers?
It is nonfoliated.
500
What type of sedimentary rock forms when water deposits tiny particles of clay in very thin, flat layers?
Shale
500
What are the four categories that geologists use to describe a rock's texture?
Grain size, grain shape, grain pattern, and no visible grain.
500
Why can limestone that began as coral reefs be found on continents?
Because plate movements have raised ancient sea floors above sea level.