The law of superposition scientists to

The law of superposition helps scientists determine the relative age of a layer of sedimentary rock. the law of superposition is a basic law of geochronology, stating that in any undisturbed sequence of rocks deposited in layers, the youngest layer is on top and the oldest on bottom, each layer being younger than the one beneath it and older than the one above it . 
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Yup no bull frogs here man