- Batholith:A Batholith is when magma forces its way into the crust but becomes trapped and solidifies into rock, it is a large mass of intrusive igneous rock believed to have solidified deep within the earth. When it cools it forms granite and this can be exposed due to weathering and erosion. They can form hilly or mountainous uplands
- Dyke:A dyke is a vertical intrusion cutting through layers of older rocks, cools rapidly on contact with surrounding colder rocks.
- Sill:A sill is a horizontal intrusion through layers of older rocks, cools rapidly on contact with surrounding colder rocks.
