Folds and Faults

Tectonic Plates

Types of Differential Stress

1 2 3

Ductile Deformation

• Rock will flow in response to stress

•Rock will change shape during flow

•Example: Copper penny on train tracks

Brittle Deformation

• Rock will break in response to stress

• Example: Glass objects, broken bones

Deforming MarbleShallow

Crust BrittleDeeper Crust

Ductile

M.S. Patterson, Australian National University

AnticlinAnticlinee

Syncline

Sinclair Dome, near Rawlings, WY

Folds

Types of Differential Stress

FaultsKanab, Utah

Fault

FaultA break in a rock along which movement has

occurred.

Normal Fault: Rock above fault plane has moved down relative to rock below

Reverse Fault:Rock above fault plane has moved up relative to rock below

Normal

Reverse

Strike-Slip

Normal Fault

Rift Valley

Reverse Fault

Jurassic Sandstone

Devonian Limestone

Thrust

Fault

Thrust Fault

San Andreas Fault

Carrizo Plain, CA