Fault (geology) | a fracture, or break, in the Earth's crust

Author: Leandro Alegsa Creation date: November 13, 2022

A fault is a fracture, or break, in the Earth's crust (lithosphere). Some faults are active. Here, sections of rock move past each other. This sometimes makes earthquakes.

Faulting occurs when shear stress on a rock overcomes the forces which hold it together. The fracture itself is called a fault plane. When it is exposed at the Earth's surface, it may form a cliff or steep slope called a fault scarp.

The angle between the fault plane and an imaginary horizontal plane is called the dip angle of the fault. Faults may dip shallowly or steeply.

Faults are categorized into three types:

Questions and Answers

Q: What is a fault?

A: A fault is a fracture, or break, in the Earth's crust (lithosphere).

Q: What happens when sections of rock move past each other?

A: When sections of rock move past each other it can sometimes cause earthquakes.

Q: What causes faulting?

A: Faulting occurs when shear stress on a rock overcomes the forces which hold it together.

Q: What is the name for the fracture itself?

A: The fracture itself is called a fault plane.

Q: How does a fault plane appear at the Earth's surface?

A: When it is exposed at the Earth's surface, it may form a cliff or steep slope called a fault scarp.

Q: What is the angle between the fault plane and an imaginary horizontal plane called?

A: The angle between the fault plane and an imaginary horizontal plane is called the dip angle of the fault.

Q: How are faults categorized?

A: Faults are categorized into three types.