18 a sandstone with a pinkish or reddish colo...
18 a sandstone with a pinkish or reddish color ... a sandstone with a pinkish or reddish color that is the result of oxidation of iron - bearing minerals indicates the sand was multiple choice deposited on land and exposed to air deposited offshore in or near a reef deposited offshore via a turbidity current deposited offshore but strongly mixed with organic material
Answer
# Brief Explanations:
Oxidation of iron - bearing minerals in sandstone occurs when sand is deposited on land and exposed to air, as oxygen in the air reacts with iron. In other environments like near reefs, via turbidity currents, or with strong organic - matter mixing, the conditions for this specific type of iron oxidation are not as prevalent.
# Answer:
deposited on land and exposed to air