What rock type does the principle of superposition apply to and how is the principle of superposition used to study the history of life on earth?

Sedimentary rocks

The principle of superposition is the basic principle of geology, which states that on examining the sequence of the strata, the stratum that is younger lies as the top whereas the older one rests at the bottom. This principle applies to the sedimentary rocks. As, the sediments are formed and piled one over the other, the compaction of the sediments occurs due to heat and pressure will result in formation of the sedimentary rocks.

the answer is 12 as i may remember

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