Post on 05-Jan-2016
description
Kinds of FaultsKinds of Faults
FaultsFaults
Is a break in Earth’s crust where slabs of Is a break in Earth’s crust where slabs of crust slip past each other.crust slip past each other.
Usually occur along plate boundaries , Usually occur along plate boundaries , where the forces of plate motion where the forces of plate motion compress, pull, or shear the crust so compress, pull, or shear the crust so much that the crust breaks.much that the crust breaks.
Three Types of FaultsThree Types of Faults
Normal FaultsNormal Faults Reverse FaultsReverse Faults Strike-Slip FaultsStrike-Slip Faults
Fault TerminologyFault Terminology
Fault Plane - the plane along which the Fault Plane - the plane along which the rock or crustal material has fracturedrock or crustal material has fractured
Hanging Wall Block - the rock material Hanging Wall Block - the rock material which lies above the fault planewhich lies above the fault plane
Footwall Block - the rock material which Footwall Block - the rock material which lies below the fault plane. lies below the fault plane.
Hanging vs. FootHanging vs. Foot
The The footwallfootwall of a fault is always of a fault is always underunder the the faultfault
The The hanginghanging wall of a fault is always wall of a fault is always aboveabove the fault the fault
Normal FaultsNormal Faults
Caused by tension forces where plates Caused by tension forces where plates divergediverge
The fault is at an angleThe fault is at an angle One block lies above the fault (hanging One block lies above the fault (hanging
wall)wall) The other block lies below the fault The other block lies below the fault
(footwall)(footwall) When movement occurs along a normal When movement occurs along a normal
fault, the fault, the hanginghanging wall slips wall slips downwarddownward
Normal FaultsNormal Faults
Normal FaultNormal Fault
Hanging Wall
Footwall
Normal FaultsNormal Faults
Normal FaultsNormal Faults
Normal FaultsNormal Faults
Reverse FaultsReverse Faults
Caused by compression forces along Caused by compression forces along convergent plate boundariesconvergent plate boundaries
Has the same structure as a normal fault, Has the same structure as a normal fault, but blocks move in opposite directionbut blocks move in opposite direction
One side lies at an angle above the otherOne side lies at an angle above the other Where the Where the hanging wallhanging wall is displaced is displaced
upwardupward relative to the footwall relative to the footwall OROR where the footwall is displaced where the footwall is displaced
downward relative to the hanging wall downward relative to the hanging wall
Reverse FaultReverse Fault
Reverse FaultReverse Fault
Hanging Wall
Footwall
Reverse FaultReverse Fault
Reverse FaultReverse Fault
Reverse FaultReverse Fault
Strike-Slip FaultStrike-Slip Fault
Created by shearing along transform Created by shearing along transform boundariesboundaries
Rocks on either side of fault slip past Rocks on either side of fault slip past each other sideways with little up-or-each other sideways with little up-or-down motiondown motion
Strike-Slip FaultsStrike-Slip Faults
Strike-Slip FaultStrike-Slip Fault
Strike-Slip FaultStrike-Slip Fault
Strike-Slip FaultStrike-Slip Fault
Strike-Slip FaultStrike-Slip Fault
Whose Fault?Whose Fault?Side View
Whose Fault?Whose Fault?Side View
Whose Fault?Whose Fault?Birds-eye View
Whose Fault?Whose Fault?Side View
Whose Fault?Whose Fault?Side View
Whose Fault?Whose Fault?Birds-eye View
Whose Fault?Whose Fault?Side View