Definition
 Types of faults with examples
Normal fault
Reverse fault
Strike - Slip fault
 Parts of a fault
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A fault is a planar fracture or discontinuity
in a volume of rock, across which there has
been significant displacement along the
fractures as a result of earth movement.
Large faults within the Earth's crust result
from the action of tectonic forces. Energy
release associated with rapid movement on
active faults is the cause of most
earthquakes.
Normal fault (slide)
 Reverse fault (jump)
 Strik-slip

A normal fault is a dip-slip fault in which the block above the
fault has moved downward relative to the block below. The
hanging wall has slipped down in comparison to the foot
wall. Gravity causes the hanging wall to slip down. Normal
Faults are from layers being pulled apart.
Normal faults generally occur in places where the lithosphere is
being stretched. Consequently they are the chief structural
components of many sedimentary rift basins where they have
major significance for hydrocarbon exploration. E.g. the North
Sea.
A reverse fault is a dip-slip fault in which the upper block, above
the fault plane, moves up and over the lower block. This type of
faulting is common in areas of compression, such as regions
where one plate is being sub ducted under another.
The hanging wall has slipped up in comparison to the foot wall.
When layers are pushed together this is the kind of fault that
occurs.
A reverse fault occurs primarily across lithological units where
as a thrust usually occurs within or at a low angle to lithological
units. It is often hard to recognize thrusts because their
deformation and dislocation can be difficult to detect when
they occur within the same rocks without appreciable offset of
lithological contacts.
The Sierra Madre fault zone of southern California is
an example of reverse-fault.
A strike-slip fault is a fault on which the two blocks slide past
one another. These faults are identified as either right-lateral
or left lateral depending on whether the displacement of the
far block is to the right or the left when viewed from either
side.
Transform faults within continental plates include some of the
best known examples of strike-slip structures, such as the San
Andreas Fault, the Dead Sea Transform, the North Anatolian
Fault and the Alpine Fault. The San Andreas Fault in California
is an example of a right lateral fault:
Type of fault
Type of force
Vertical or
horizontal
motion
Type of plate
boundary
Type of
Earthquackes
Normal
Tension
Vertical
Divergent
Shallow &
intermediate
Reverse
Compression
Vertical
Convergent
All types
Strike-slip
Shearing
Horizontal
Transform
Shallow