Science Olympiad Dynamic Planet Practice Test

What describes the motion of rocks in an oblique slip fault?

1. The rocks move only up or down

2. The rocks move in a combination of vertical and horizontal directions

3. The rocks slide past each other laterally only

4. The rocks experience no movement

The correct answer is: The rocks move in a combination of vertical and horizontal directions

In an oblique slip fault, the rocks exhibit a unique movement characterized by both vertical and horizontal displacements. This movement occurs due to the combination of shear stress and normal stress acting on the fault plane, resulting in rocks moving not just upwards or downwards, but also laterally. The term "oblique" signifies that the motion is not purely vertical (which is seen in normal or reverse faults) or purely horizontal (typical of strike-slip faults), but rather a mix of both. This characteristic is essential for understanding the geological forces at play in such faults, which often develop in complex tectonic settings where multiple stresses are at work. Recognizing this dual movement helps in comprehending the broader implications for geological structures and landscape evolution, as oblique slip can influence the formation of features like fault-block mountains and can result in significant seismic activity.