The development of radiometric dating techniques in the early 20th century allowed geologists to determine the numerical or "absolute" age of the various strata and thereby the included fossils.
Like extant organisms, fossils vary in size from microscopic, even single bacterial cells one micrometer in diameter, to gigantic, such as dinosaurs and trees many meters long and weighing many tons.
The implications of pervasive contamination and ancient variations in carbon-14 levels are steadfastly ignored by those who base their argument upon the dates….
While the method cannot be counted on to give good, unequivocal results, the numbers do impress people, and save them the trouble of thinking excessively.
Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation.
Index fossils are fossils that are known to only occur within a very specific age range.
' Richard Lingenfelter, ' Production of C-14 by cosmic ray neutrons ' , Review of Geophysics , 1963, p.51 .
A primer on radioactive decay Carbon-14 dating Radioisotope dating. Fundamental unit of matter Made up of components called subatomic particles Proton (positive charge) Neutron (no electrical charge) Dating Fossils and Rocks. Amount of stable C-12 Amount of unstable C-14 Ratio Years Dead # Half-lives 100 Trillion 100 1-T to 1 0 0 50 5,730 100 Trillion 1 2-T to 1 100 Trillion 11,460 25 2 4-T to 1 100 Trillion 8-T to 1 17,190 3 12 100 Trillion 4 22,920 6 16-T to 1 3 28,650 100 Trillion 32-T to 1 5 Richard, Milton, Shattering the Myths of Darwinism , 1997, p. ' During the 1960s, Libby ' s experiments were repeated by chemists' The new experiments, though, revealed that the discrepancy observed by Libby was not merely an experimental error ' it did exist.
Mountains have been built and eroded, continents and oceans have moved great distances, and the Earth has fluctuated from being extremely cold and almost completely covered with ice to being very warm and ice-free.
Find a fossil with a measured ratio of 16 trillion to 1 (C12 to C14) This means 4 half-lives have expired giving a date of about 23,000 years What if the ratio started at: 2 trillion to 1 : 3 half-lives instead of 4 ' age 17,000 8 trillion to 1 : 1 half-life instead of 4 ' age 5,000 Elizabeth K. Michael, ' Twenty-five Years of Radiocarbon Dating, ' American Scientist , Sep/Oct 1974 ' We know that the assumption that the biospheric inventory of C 14 has remained constant over the past 50,000 years or so is not true . Ancient human skeletons, when dated by the new Accelerator Mass Spectrometer technique, give surprisingly recent dates.
' The assumption carbon-14 dating is based upon is FALSE R. Taylor, ' Major Revisions in the Pleistocene Age Assignments for North American human Skeletons by C-14 Accelerator Mass Spectrometry ' , American Antiquity , Vol. In one study of eleven sets of ancient human bones, all were dated at about 5,000 radiocarbon years or less.
The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record.
The study of fossils across geological time, how they were formed, and the evolutionary relationships between taxa (phylogeny) are some of the most important functions of the science of paleontology.
The age of the fossil must be determined so it can be compared to other fossil species from the same time period.