Relative dating vs
Each layer has a unique layer and consists of different sediments or material.
The principle of superposition states that the layer which lies at the bottom is older than the one on top of it.
Animals evolve rapidly, and these evolution's are reflected by the variations in their bones or teeth.
When they die, their remains get fossilized and are used by scientists to determine the era in which they lived.
Most of the nitrogen contained in these fossils gets depleted progressively.
When we find two fossils in the same strata of soil, we assume that both fossils were deposited during the same time period.
If an animal fossil is found, and the time during which it lived is known, it helps us understand the time period of any other fossil found in the same strata.
The absolute age of these events need not inevitably be known.
Grand Canyon is a gorge located in Northern Arizona, USA. While some of the layers are uplifted, most of the landform is left undisturbed by nature.