Have you ever wondered how archaeologists know how old an object is? That is the question I tried to answer in this article for StoneAgeMan, and I quickly learned that there are many dating methods, each with their own particularities. I thus decided to spend several posts exploring the various dating techniques, with this first article focused on relative and radiocarbon dating methods.
Below are the first few sections of the article, with the rest being on StoneAgeMan:
Archaeological Dating Methods
Part 1: Relative and Radiocarbon Dating
A question I frequently hear about archaeology is, “How do archaeologists know how old something is?” Indeed, determining when an artifact or feature was made is a key part of learning about past civilizations.
There are several dating methods that help archaeologists figure out how old objects are. In fact, there are so many that it would be impossible to describe them all in one article. Hence, this post will discuss some of the most widely-used dating methods – stratigraphy, typology, seriation, and radiocarbon dating – and we will cover the rest in subsequent articles.
Relative Dating Methods
There are two overarching classes of dating methods: relative and absolute. Relative dating methods cannot determine the exact age of an object, but only which finds are older or younger than others. The most important relative dating method relies on a site’s stratigraphy.
When excavating an archaeological site, you can literally see the layers of dirt and debris that have accumulated over time. These layers are known as a site’s stratigraphy, and the law of superposition, first popularized by Sir William Matthew Flinders Petrie, states that the oldest stratigraphic layers are at the bottom. Thus, objects found near the top of a site are probably younger than the ones further down – unless something (like a burrowing animal) moved the items after burial.