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Deeper deposits are usually older, and each layer holds its own finds. The figure is taken from English Heritage, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the History shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

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Stratigraphy reads a site one layer at a time

Deeper deposits are usually older, and each layer holds its own finds Archaeologists record the sequence of soil layers at a site, since material sealed beneath later deposits is normally earlier. The principle was stated by geologists in the seventeenth century and adopted by excavators who saw that potsherds and coins changed from layer to layer. Undisturbed layers are evidence in themselves, so excavation destroys the record as it proceeds. It sits in Mondo's history collection, one of 200 facts that each trace back to the reference below.

Where this comes from

English Heritage

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Tags: stratigraphy, excavation, method

Stratigraphy reads a site one layer at a time: the short answers

Where does this come from, and can I check it?: Deeper deposits are usually older, and each layer holds its own finds. The figure is taken from English Heritage, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a history fact?: Yes. It sits on the History shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.