CPG Structural Geology & Tectonics Flashcards

What term describes the angle of inclination of a rock layer measured from the horizontal plane?

Answer: Dip angle

Dip is the angle of inclination measured downward from horizontal, perpendicular to the strike direction.

In structural geology, 'strike' refers to which of the following?

Answer: The compass direction of a horizontal line on a planar surface

Strike is the compass bearing of a horizontal line formed by the intersection of a planar feature with a horizontal surface.

A syncline is a fold in which rock layers:

Answer: Dip toward the fold axis

In a syncline, the rock layers dip toward the fold axis, forming a trough-shaped structure with younger rocks in the core.

Which fault type is characterized by primarily horizontal movement with little to no vertical component?

Answer: Strike-slip fault

Strike-slip faults involve lateral (horizontal) movement of one block past another along a near-vertical fault plane.

In a compressional tectonic setting, which fault type is most likely to form?

Answer: Thrust/reverse fault

Compressional stress causes shortening, which produces reverse and thrust faults where older rocks are pushed over younger rocks.

The hanging wall of a fault is defined as:

Answer: The block above the fault plane

The hanging wall is the rock mass that overlies the fault plane, while the footwall lies beneath it.