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By indicating that the oldest layer is on the bottom and the youngest layer is on the top, this is happening by using index fossils or radioactive decay dating methods in the sedimentary section.

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lived for a short time, has a wide horizontal distribution and is a single species of life

The limestone particles.

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Sedimentary rocks form near earth’s surface and most igneous and metamorphic rocks don’t. the high pressure and heat associated with metamorphic and igneous rocks would destroy any evidence of life.

The Mesozoic Era is the age of dinosaurs and there are no rocks of that age in Elmira.

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Scientific principles generally remain the same with time, thus we can interpret the past of geological history through an understanding of the present.

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Carbon-14 has a short half-life that too little would be left to measure in Ordovician age fossils. due to the age of Ordovician range from 444 to 488 million years old.

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Free Oxygen started to build up in earth’s atmosphere.

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