Question

As a geologist-in-training you observe the rock outcrop pictured above on a field trip. You notice that a lower sandstone layer is tilted at an angle of 85 degrees to the east. Immediately overlaying the sandstone is a siltstone layer that is tilted 25 degrees to the west. What can you conclude from this stratigraphic relationship?

Answer 1

Answer:

Angular unconformity

Explanation:

An angular unconformity is the contact that separates a younger, gently dipping rock unit from older underlying rocks that are tilted or deformed layered rock. The contact is more obvious than a disconformity because the rock units are not parallel and at first appear cross‐cutting. Angular unconformities generally represent a longer time hiatus than do disconformities because the underlying rock had usually been metamorphosed, uplifted, and eroded before the upper rock unit was deposited