The concept that the oldest rock layers are at the bottom of a sequence with younger rock layers deposited on top of them. This can be considered a rule that applies in all situations, except where the rocks are extremely deformed.
Related terms:
The concept that the oldest rock layers are at the bottom of a sequence with younger rock layers deposited on top of them. This can be considered a rule that applies in all situations, except where the rocks are extremely deformed.
Related terms: