How does absolute age differ from relative age?

Question

Leo Arens · Accepted Answer

One has an explicit date and the other is relative

To view my answer to this query about the dating of fossils, click this link. In short, absolute dating is a technique by which isotopes of a certain element are measured and then using a particular decay system (for example, #U-Pb#) an age can be constructed. This will give you a number and then you would calculate an associated uncertainty. For example, I may date a zircon mineral by measuring U and Pb and get an age of 2013 #+-# 15 Ma ( Ma = million years ago). If I were to date something relatively, I could tell you what came first, second, third, and so on, but I wouldn't know if it happened 10 minutes ago or 4 billion years ago. I could tell you the order in which geological events occurred, but I wouldn't know how long ago they occurred!

Santiago Arce · Answer

undefined Absolute age refers to the exact age of a rock, fossil, or geological event determined through techniques such as radiometric dating, which measures the decay of radioactive isotopes. Relative age, on the other hand, refers to the age of a rock layer or fossil compared to other rocks or fossils, typically determined through principles like superposition and cross-cutting relationships.