Fossil record dating assumptions
New dating methods are invented all the time, however, most have practical limitations.
Geologic research and mapping requires the determinations of the ages and composition of rocks.
A geologic map or report typically is only a summary of investigations that frequently involve the collecting and processing of hundreds of rock samples, followed by the evaluation and interpretation of data from a variety of analytical techniques.
“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.The short answer is: scientists use the rocks to date fossils they think should be very old.And that wouldn’t be such a bad thing if they didn’t also turn right around and use the “age” of the fossils to date the rocks they are found in too!Relatively young deposits can be sometimes dated using tree rings, varved-lake sediments, coral growth patterns, and other methods.Paleontology is the study of life in past geologic periods (fossil plants and animals), incorporating knowledge of an organism's phylogeny, relationships to existing organisms, and correlation to an established chronology of Earth History.