archaeologicaldatingmethods. archaeological dating methods 1.relative dating (aka...

Archaeological

Dating

Methods

archaeological

dating methods

1. relative dating (aka “older/younger”

dating)

2. chronometric dating

(aka “absolute” dating)

Relative and Chronometric Dating

Understanding Humans, 10th Ed., p. 189.

Understanding Humans, 10th Ed., p. 188.

REMEMBER: relative

methods

tell you whether something is

older / younger / the same age

methods

Understanding Humans, 10th Ed., p. 188.

REMEMBER: chronometric

methods

yield a date

often scaled in calendar years

+/- a number of years (there is a

margin of error in every technique)

Stratigraphy

the sequence of geological strata, or layers, formed

by materials deposited by water or wind

-Law of association

-Law of superposition

Otero, S. (2004) Social and Behavioural Science Lecture

Notes (2014). El Camino College, Torrance, California

Main gorge at Olduvai. Note geological beds.

Understanding Humans, 10th Ed., p. 197.

Hoebel, Anthropology: The Study of Man and Archaeology, 4th Ed., p. 153.

Olduvai Gorge, Kenya.

Bed I

Note how stratigraphy is used to date

stone tools

archaeological

dating methods

1. relative dating

2. chronometric dating

(aka “absolute” dating)

provides estimates in actual numbers of

years

(sometimes +/-)

Relative and Chronometric Dating

Understanding Humans, 10th Ed., p. 189.

chronometric dating

(aka “absolute” dating)

determining the actual age of geological deposits (and the

fossils in them) by examining the chemical composition of

rock fragments and organic remains containing radioactive

substances such as uranium 238, and C 14, which decays at

a known rate. It is a destructive method.

Direct determination of age determined

through laboratory analysis

Here are three examples you need to know:

C14 dating of organic samples

Dendrochronology (tree ring patterns)

Molecular clocks (slight genetic markers that change at a

known rate)

Relative and Chronometric Dating

Understanding Humans, 10th Ed., p. 189.

Technician in a radiocarbon dating laboratory.

Understanding Humans, 10th Ed., p. 194.

Radiocarbon dating:

Don’t stress out; I will

NEVER ask you to

explain how it works

• Method was developed in the

1940’s by Willard Libby and a team

of scientists at the University of

Chicago.

• Very powerful in dating artifacts

and geological events up to about

50,000 years ago.

So, if relative dating techniques

do not give you a specific age

and chronometric dates give

you a date range, how do

archaeologists choose which

dating technique to use?