ASSIGNMENT : FAULTS

ASSIGNMENT : FAULTS

NAME

: TAN LING SAN

MATRIX : E12A317

DATE

: 14/09/2014

What causes normal fault and how it formed cliff and mountains?

-Normal fault is an inclined dip-slip fault in which hanging wall has moved downward where footwall has moved upward.

-When the hanging wall moves downward and the footwall moves upward, fault scarp will form as shown in the Agram below. This fault scarp is the created cliff.

-Examples : the Teton Range in Wyoming and the Hurricane Cliffs, west of Zion National Park in Utah.

-Horst is a block pushed upward between faults while graben is a block that has dropped between faults. Horst and graben together can form mountain. As shown in the diagram below, graben represents the low-lying areas such as valleys while horst is the higher area.

-Examples : the Condroz and Ardennes regions of Wallonia.

Explain how rollover anticline occurs in listric normal fault.

-The diagram above gives an illustration on how rollover anticline occurs in listric normal fault.

-Rollever anticline formed when hanging wall slumps into the low pressure extensional zone associated with listric normal faulting.

-Listric normal fault is a curvd normal fault in which the fault surface concave upwards. The dip decreases with increasing depth.

-Examples: the Mardin High in southeast Turkey.

Give a brief explanation of drag fold formation with a simple illustration.

-Drag fold is a secondary folding of bedding in the vicinity of the fault plane due to secondary stress.

-They represent the bending of rocks before it breaks.

-Drag folding must precede the actual breakage of the rock in a fault.

-Example: the Oakland Hills in the San Francisco Bay area.