The two laws that describe the relative age of rocks are:
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Law of Superposition: This geological principle states that in any undisturbed sequence of sedimentary rocks, the oldest layers are at the bottom, and the younger layers are at the top. This principle allows geologists to determine the relative ages of rock layers.
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Principle of Original Horizontality: This principle states that layers of sediment are originally deposited horizontally under the action of gravity. If rock layers are found tilted or folded, it indicates that they have been disturbed after their formation, helping geologists infer the relative timing of geological events.
Together, these laws help geologists interpret the geological history of an area and establish the relative ages of rock layers.