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Fossil correlation dating technique

The periods of relative quiet contribute only a small part of the record.

“To test this idea, we matched earliest Cambrian records of carbon isotope variability from Siberia, Mongolia, and China with a Moroccan record constrained by five radiometric ages from interbedded volcanic ashes.

Stratigraphic disorder is produced by the physical or biogenic mixing of fossiliferous sediments, and the reworking of older, previously deposited hard parts into younger sediments.

Since these processes occur to an extent in virtually all sedimentary systems, stratigraphic disorder at some scale is probably a common feature of the fossil record.” (Cutler, Alan H., and Karl W.

This is supposed to be hard-headed pragmatism.” (O’Rourke, J.

E., “Pragmatism Versus Materialism in Stratigraphy,” , vol. 47.) “One might imagine that direct methods [radiometric dating] of measuring time would make obsolete all of the previous means of estimating age, but these new ‘absolute’ measurements are used more as a supplement to traditional methods [index fossils] than as a substitute.

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