Intrusive volcanic activity Flashcards
1
Q
How do batholiths form?
A
When large chambers of magma cool underground they form domes of igneous rock
2
Q
How do dykes and sills form?
A
Where magma has flowed into gaps in the surrounding rock and cooled it forms vertical dykes (across the layers of rock) and horizontal sills (between the layers of rock)
3
Q
What are cooling cracks?
A
Cracks that form as the magma cools. In a sill they’re vertical and in a dyke they’re horizontal
