Initially, the students are asked to develop physical clues to put themselves in order from youngest to oldest (exposing the inferences we make unconsciously about people's ages), and this will be refined/modified using a list of current events from an appropriate historical period that more and more of the students will remember, depending on their age (among other variables).Absolute age is introduced by having the students order themselves by birth decade, year, month, and day, and comparing the absolute age order to the order worked out in the relative-dating exercise, with a discussion of dating precision and accuracy.
Before this, archaeologists and scientists relied on deductive dating methods, such as comparing rock strata formations in different regions.
Chronometric dating has advanced since the 1970s, allowing far more accurate dating of specimens.
As an example of how they are used, radiometric dates from geologically simple, fossiliferous Cretaceous rocks in western North America are compared to the geological time scale.
To get to that point, there is also a historical discussion and description of non-radiometric dating methods.
The regular order of occurrence of fossils in rock layers was discovered around 1800 by William Smith.
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. 1979, 1986 © Harper Collins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Cite This Source (rā'dē-ō-mět'rĭk) A method for determining the age of an object based on the concentration of a particular radioactive isotope contained within it.Geochronologists do not claim that radiometric dating is foolproof (no scientific method is), but it does work reliably for most samples.It is these highly consistent and reliable samples, rather than the tricky ones, that have to be falsified for "young Earth" theories to have any scientific plausibility, not to mention the need to falsify huge amounts of evidence from other techniques.Chronometric dating, also known as chronometry or absolute dating, is any archaeological dating method that gives a result in calendar years before the present time.Archaeologists and scientists use absolute dating methods on samples ranging from prehistoric fossils to artifacts from relatively recent history.Photo from Glen Canyon National Recreation Area, Utah.