Anth 140
Summer 2007
Lab 2: Archaeological Dating Methods
Name:
ID:
Station 1: Carbon-14 Dating
Circle the correct answer:
Using the picture below and the handout,
please answer the following questions:
1. C-14 forms from the interaction of Cosmic rays
with N-14 by____ and C-14 reverts back to N-14
by____.
a. beta decay and neutron capture
b. electron loss and electron capture
c. neutron capture and beta decay
d. proton capture both ways
e. no way to know
2. Of the three isotopes of carbon, which is most
abundant and which is radioactive?
a. C-12 & C-13
b. C-13 & C-14
c. C-14 & C-12
d. C-12 & C-14
e. no way to know
3. Because of interaction and exchange with
atmosphere and oceans, all living tissue maintains a
fixed proportion of C-14. After death, the amount of
C-14 begins to decrease.
a. True
b. False
4. A C-14 date estimates the time since the death of
once-living things, up to about 50,000 years. Which
of the following materials CANNOT be dated by this
method?
a. bones
b. wood
c. soil
d. pottery with imbedded charcoal
e. volcanic ash from Pompeii
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Anth 140
Summer 2007
Using the chart below and the handout, please answer the following questions:
Half Life
0
1
2
3
4
5
6
7
8
9
10
Approx. %
Remaining
100%
50%
25%
12.5%
6.25%
3.13%
1.56%
.78%
.39%
.2%
Circle the correct answer:
5. What % of C-14 remains in a carbon-bearing material after 3 half-lives of time have gone by?
a. 50%
b. 25 %
c. 12.5%
d. 6.25%
e. 0.39%
6. How many half-lives of time have passed when only a little more than 3% of a sample original
C-14 still remains?
a. 1
b. 3
c. 5
d. 7
e. unknown
7. How much daughter N-14 can be found in a buried ancient tree stump that is 4 half-lives old?
a. 6.25%
b. 93.75%
c. 4%
d. 96%
e. Very little since N-14 is a gas and escapes from the material
Anth 140
Summer 2007
8. Using the calculator function on the lab computers to help you, please manually calculate how
old an artifact is if you had 30 percent carbon-14 remaining compared to a living sample (use the
example calculation from the handout to help you).
Using one of the lab computers and the website http://www.101science.com/Carbon14.htm ,
please answer the following questions:
9. How much Carbon-14 is left after 5,500 years have passed? (type in the number of years and
click on Calculate).
10. How many years have elapsed if your sample still contains 40% Carbon-14? (type in the
C-14 percent and click on Calculate).
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Anth 140
Summer 2007
Station 2: Seriation
Using seriation (i.e. the principal of battleship curves), please arrange the 10 strips of paper with
ceramic vessels in their relative chronological order and answer the questions below. Note that
the strips of paper all align evenly and you are placing the sites in the order that they occurred,
from top to bottom. Make sure each pottery style approximates a battleship curve. Please ask us
if you have any questions!!!
11. Record the chronological order of the pottery using the site numbers provided.
(i.e. 3, 2, 7, 5, etc).
12. What other artifacts besides pottery could be used to create chronologies using seriation?
Why?
Station 3: Dendrochronology
13. Suppose the piece of wood illustrated here comes from the foundation of a historic,
undated building. Using the master sequence represented below, what is the earliest date that
the building could have been constructed?
Historic building
foundation
Anth 140
Summer 2007
14. Using what you know about dendrochronology and carbon-14 from the handouts, please
explain what the benefits and drawbacks of using dendrochronology and radiocarbon dating
are for determining accurate dates.
Station 4: Dating techniques
Station 4 consists of different artifacts which can be dated through various techniques. Please
use the “dating techniques” handout to determine which techniques are the most appropriate for
dating the various artifacts. Please choose 3 different artifacts and list the dating technique that
is best suited for each artifact. If multiple dating techniques exist, please list them all. For each
artifact please also list the strengths and limitations of each technique.
15. Artifact 1:____________
Appropriate dating technique(s):
Strengths/Limitations:
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Anth 140
Summer 2007
16. Artifact 2:____________
Appropriate dating technique(s):
Strengths/Limitations:
17. Artifact 3:____________
Appropriate dating technique(s):
Strengths/Limitations:
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