Topic 6: Dating Techniques

Question 1

What are some issues with dating? what do you need to properly date a site/material culture?

Answer 1

• NEED context to accurately date something.
• Context is everything in dating, without context dates are meaningless.
• you also need multiple dates to ensure the accuracy and precision of the dates obtaining. One date is no dates!

Question 2

What is accuracy?

Answer 2

• the closeness of a chronometric age determined to the real age.
• If we need to choose one, we prefer accuracy over precision

Question 3

what is precision?

Answer 3

• the total chronometric age range the true age should lie withing (with a given level of confidence/size of error)
• example 1500 yrs plus or minus 5 years

Question 4

What is relative dating? 3 different kinds?

Answer 4

• simply indicates that something is older or younger, based on comparison
• three kinds are
• chronological sequencing (seriation, stratigraphic dating)
• dating by association (associated with animal/artifacts of a known age)
• terminus quem (post or ante quem)

Question 5

what is absolute/chronometric dating?

Answer 5

• provides actual ages of material culture/cites
• this is ALWAYS the goal in archaeology

Question 6

what is terminus quem? Ante quem? Post quem?

Answer 6

• dating based on a known historical date/event (the terminus)
• Terminus ante quem is the LATEST date an event may have occured or an item was made/used
• terminus post quem is the EARLIEST date an evet may have happened or an item was used

Question 7

What are the basic principles of stratigraphy? (main 2)

Answer 7

• law of superposition
• law of original horizontality

Question 8

What are the 3 other principles of stratigraphy? (other than superstition and original horizontality?)

Answer 8

• principles of association
• principle of reversal
• principle of intrusion

Question 9

what is the law of superposition?

Answer 9

Layers are successively deposited, one after another, such that the oldest layers are on the bottom and the youngest at the top

Question 10

What is the law of original horizontality?

Answer 10

• Deposits are laid down horizontally
• Deviations are caused by either uplifting or downfall

Question 11

What is the principle of association?

Answer 11

items found together in the same deposit are of essentially the same age

Question 12

What is the principle of reversal?

Answer 12

deposits may have been removed from site and redeposited in reverse order

Question 13

What is the principle of intrusion?

Answer 13

intrusion must be more recent than the deposits through which it cuts

Question 14

What is Typology? Why can it help with dating?

Answer 14

• systematic organization of artifacts into types base on shared attributes
• products of a given period and place have a distinctive style! this can help us relative date

Question 15

What is seriation? How does it relate to typology?

Answer 15

• A relative dating technique based on the chronological ordering of a group of assemblages, where the most similar are placed adjacent to each other
• Taking typology, recognizing change over time, and arranging it in a relative sequence.

Question 16

4 conditions for proper seriation?

Answer 16

1. Objects or assemblages being seriated must belong to the same cultural tradition
2. Materials being seriated should some from a restricted geographical area (same area, same peoples) larger areas complicate this
3. It is important to recognize situations that can produce sudden changes in the cultural and stylistic traditions of a region (migration, raw material loss, sudden shift)
4. Since no assumption is made about the directed in which change is taking place, it is essential to establish the proper chronological order of the sequence by referring to some kind of external evidence (no linear path)

Question 17

what is contextual seriation based on? frequency seriation?

Answer 17

• Contextual seriation is based on the duration of different artifacts. can be used to order assemblages found in different sites.
• Frequency seriation is based on the idea that a style becomes popular, reaches a peak, and then declines as a new styles replace it. The frequency of artifact styles within an assemblage in one site should be similar to one another.

Question 18

What is tree ring dating/dendrochronology? What are 2 issues with it?

Answer 18

• dating trees/wood materials based on the growth rings
• can be used to directly date wood found in archaeological sites, such as building timbers.
• issues with this are: only dates when the tree was felled/killed. People in the past may have used old wood thereby creating a false chronology. As well, it is a destructive method of dating (you need a core sample of the material)

Question 19

What is C14 dating? How is it used, and what can it be used on?

Answer 19

• Radiocarbon dating.
• can only be used on organic material that contain carbon, so nothing non-organic.
• Radiocarbon dating is done by measuring the relative proportions of radioactive C14 to stable C12/13, as C14 decays to C12/13.
• in other words, when you die you are at 100% C14, after you die you stop exchanging C14 with the atmosphere, and the C14 will slowly stabilize to C12/13.

Question 20

why can’t you radiocarbon date fossils?

Answer 20

• because during fossilization organic materials are replaced with minerals, and thus the carbon is replaced.
• no carbon to date!

Question 21

some of the limitations with radiocarbon dating?

Answer 21

• can only be used on organic materials that have carbon.
• this dating method assumes that there has been a constant amount of 14 in the atmosphere over time.
• assumes that the amount of C14 in the dated material remains constant since deposition, but this can be altered due to contamination.

Question 22

How do we select an appropriate dating technique?

Answer 22

• when possible archaeologists will always want to know actual ages rather than relative ages
• but due to material type of artifact, preservation, matrix, ect, we cannot always do absolute dating, such as carbon dating or dendrochronology

Question 23

What is a residual sample?

Answer 23

a sample that has eroded into a different context/ cuts into a different context in stratigraphy. Causes overestimation the age of the pit contents.

Question 24

What is an invasive sample?

Answer 24

An invasive sample is one that moves from an upper horizon to a lower horizon in stratigraphy. It causes an underestimation of the lower horizons age.

Question 25

Who was Nicholas Steno?

Answer 25

Danish scientist who created 4 of the defining principles/laws of stratigraphy (including the law of superposition and the principle of original horizentality)