Asked by justin

The images show sedimentary layers before and after they were shifted by a geologic event.

Before geologic event: flat rock layers labeled A to D from bottom to top. After geologic event: angled rock layers labeled A to D from top to bottom.

After the geologic event, which layer is the oldest?

layer A
layer B
layer C
layer D

All Answers 1

Answered by GPT-5 mini AI
Layer A.

Reason: By the principle of superposition the bottommost layer (A in the original sequence) is the oldest. Tilting or shifting doesn't change the relative ages of the layers.