Kinds of Faults
Faults Is a break in Earth’s crust where slabs of crust slip past each other. Usually occur along plate boundaries , where the forces of plate motion compress, pull, or shear the crust so much that the crust breaks.
Three Types of Faults Normal Faults Reverse Faults Strike-Slip Faults
Fault Terminology Fault Plane - the plane along which the rock or crustal material has fractured Hanging Wall Block - the rock material which lies above the fault plane Footwall Block - the rock material which lies below the fault plane.
Hanging vs. Foot The footwall of a fault is always under the fault The hanging wall of a fault is always above the fault
Normal Faults Caused by tension forces where plates diverge The fault is at an angle One block lies above the fault (hanging wall) The other block lies below the fault (footwall) When movement occurs along a normal fault, the hanging wall slips downward
Normal Faults
Normal Fault Footwall Hanging Wall
Normal Faults
Normal Faults
Normal Faults
Reverse Faults Caused by compression forces along convergent plate boundaries Has the same structure as a normal fault, but blocks move in opposite direction One side lies at an angle above the other Where the hanging wall is displaced upward relative to the footwall OR where the footwall is displaced downward relative to the hanging wall
Reverse Fault
Reverse Fault Hanging Wall Footwall
Reverse Fault
Reverse Fault
Reverse Fault
Strike-Slip Fault Created by shearing along transform boundaries Rocks on either side of fault slip past each other sideways with little up-or-down motion
Strike-Slip Faults
Strike-Slip Fault
Strike-Slip Fault
Strike-Slip Fault
Strike-Slip Fault
Whose Fault? Side View
Whose Fault? Side View
Whose Fault? Birds-eye View
Whose Fault? Side View
Whose Fault? Side View
Whose Fault? Birds-eye View
Whose Fault? Side View