Rock Types
This type of rock forms when magma cools and hardens.
What is igneous rock?
Rocks change over long periods of this amount of time.
What are millions or billions of years?
The country where the Nuvvuagittuq Greenstone Belt is located.
What is Canada?
Earth’s outer layer is divided into these.
What are plates?
These processes slowly wear away rock layers.
What are weathering and erosion?
This type of rock forms from compacted and cemented sediment.
What is sedimentary rock?
The process that turns sediment into sedimentary rock.
What is compaction and cementation?
This is how old the Greenstone Belt is.
What is about 3.8–4.3 billion years old?
This process happens when one plate moves under another.
What is subduction?
This exposed the Greenstone Belt at Earth’s surface.
What is erosion removing upper layers?
This type of rock forms when heat and pressure change existing rock.
What is metamorphic rock?
Heat and pressure cause this type of change in rocks.
What is metamorphism?
The Greenstone Belt is one of the ______ rock formations on Earth.
What are the oldest?
This process pushes rock upward to the surface.
What is uplift?
The Greenstone Belt was buried deep due to this process.
What is subduction?
This rock type forms without melting.
What is metamorphic rock?
This happens when rocks are broken down and moved by wind, water, or ice.
What is weathering and erosion?
The rock formations have stayed together for this long.
What is billions of years?
This drives plate movement inside the Earth.
What is energy inside Earth?
This caused the Greenstone Belt to become metamorphic.
What is heat and pressure deep underground?
The two types of rock that originally made up the Greenstone Belt.
What are igneous and sedimentary rocks?
The type of rock the Greenstone Belt became after transformation.
What is metamorphic rock?
The Greenstone Belt is nearly this shape today due to erosion.
What is nearly flat?
These processes move rocks deep underground and back up again.
What are subduction and uplift?
These processes “never stop” according to the article.
What are plate movement and rock transformations?