Dating rocks and fossils and geologic events
2 Use Index Fossils to Date Rocks and Events Name: _________________________________________ Course/Section: _________________________________Materials: Pencil, calculator.
Dating of Rocks, Fossils, and Geologic Events • 189ACTIVITY 8.
This approach avoids the circularity associated with using fossils to correlate rocks, and then using those correlations to infer biological patterns…” (“Cambrian Explosion: New Timeline for Appearances of Skeletal Animals in Fossil Record,” , Nov.These layers of sedimentary rock contain billions of fossil remains. The layers are arbitrarily arranged into a specific order (not necessarily the order in which they are found).This order reflects the assumption of biologic evolution.Apart from very ‘modern’ examples, which are really archaeology, I can think of no cases of radioactive decay being used to date fossils.” (Ager, Derek V., “Fossil Frustrations,” , vol. 425.) “The larger part of the Phanerozoic time scale…relies on a construction where stages are first scaled ‘geologically’ with biostratigraphic compositing techniques, and then stretched in linear time using key radiometric dates. E., “Pragmatism Versus Materialism in Stratigraphy,”, vol. 53) “A great deal has changed, however, and contemporary geologists and paleontologists now generally accept catastrophe as a ‘way of life’ although they may avoid the word catastrophe.In fact, many geologists now see rare, short-lived events as being the principal contributors to geologic sequences….