Fault: Transform

Novice Spanish

How do the plates accommodate motion near spreading ridges?

A transform fault is a type of strike-slip fault wherein the relative horizontal slip is accommodating the movement between two ocean ridges or other tectonic boundaries. They are connected on both ends to other faults. A transform fault or transform boundary, also known as conservative plate boundary since these faults neither create nor destroy lithosphere, is a type of fault whose relative motion is predominantly horizontal. Additional animations on seafloor spreading and transform faults are available from Tanya Atwater (http://emvc.geol.ucsb.edu/2_infopgs/IP1GTect/eSoAtlantic_CutGlobe.html).

Objectives:

  • A transform fault  accommodates relative horizontal slip between other tectonic elements, such as oceanic plates
  • A transform fault has strike-slip motion
  • It is connected on both ends to other faults

Keypoints:

  • A transform fault  accommodates relative horizontal slip between other tectonic elements, such as oceanic plates
  • A transform fault has strike-slip motion

Related Animations

In a strike-slip fault, the movement of blocks along a fault is horizontal. The fault motion of a strike-slip fault is caused by shearing forces. Other names: transcurrent fault, lateral fault, tear fault or wrench fault. Examples: San Andreas Fault, California; Anatolian Fault, Turkey.

Animation Novice

Animation shows the buildup of stress along the margin of two stuck plates that are trying to slide past one another. Stress and strain increase along the contact until the friction is overcome and rock breaks.

Animation Novice

In a normal fault, the block above the fault moves down relative to the block below the fault. This fault motion is caused by extensional forces and results in extension. Other names: normal-slip fault, tensional fault or gravity fault. Examples: Sierra Nevada/Owens Valley; Basin & Range faults.

Animation Novice

New oceanic crust is created at this boundary when basalt magma, formed in the mantle, rises into fractures in the crust and solidifies. Spreading ridges are high elevation because the young oceanic plate at the ridge crest is hot and less dense than the older, colder and more dense plate on the flanks of the ridge. 

Animation Novice

Left-lateral fault strike slip fault with little or no friction along fault contact. There is no deformation of the rock adjacent to contact. If the block opposite an observer looking across the fault moves to the left, the motion is termed left lateral.

Animation Novice

Left-lateral fault strike slip fault with low friction along fault contact. There is no deformation of the rock adjacent to contact. If the block opposite an observer looking across the fault moves to the left, the motion is termed left lateral. Example: the San Andreas Fault of California

Animation Novice

Related Videos

Video lecture covers three basic types of tectonic plate boundaries.

Video Novice