Deforming the Earth’s Crust

Beth Roland

Team 5 Mountaineers

Eighth Grade Science

Deformation

• Deformation is the process by which a rock changes shape

Deformation

Compression-Occurs when a rock Layer is squeezed-Converging platesCreate mtn ranges

Tension-Occurs when forces pull

or stretch rock layers-diverging plates create-mid-ocean ridges and

faults

Folds in the Geologic Column

• Folding is the bending of rock layers because of stress in the Earth’s crust.

Types of Folds

Anticline- upward Arching fold

Syncline- DownwardArching fold

Monocline- folded in Between 2 horizontal

ends

Faulting• Faulting is the breakage of rock caused when

stress is applied to them. The surface along which the layers slide past each other is called a fault.

• Normal Faults-when a normal fault moves the hanging wall moves downward relative to the footwall.

Faulting

• Reverse Faults- when a reverse fault moved the hanging wall moves up relative to the footwall.

San Andres Fault