3.5.
U
C DATING FOR ABSOLUTE CHRONOLOGY OF EASTERN MEDITERRANEAN CULTURES IN
THE SECOND MILLENNIUM BC WITH ACCELERATOR MASS SPECTROMETRY
(ABSOLUTE CHRONOLOGY V)
Walter Kutschera and Peter Stadler
TABLE OF CONTENTS
1.
Summary
14
2.
C dating with Accelerator Mass Spectrometry
2.1. UC dating
2.2. VERA-The Vienna Environmental
3.
3.1.
3.2.
3.3.
3.4.
3.4.
Research Accelerator
Archaeological Aspects
Status of the Absolute Chronology
of Civilisations in the Eastern Mediterranean
in the Second Millennium BC
Other currently ongoing projects
Directions for our project
Selection of Samples
Selection by Time
Selection by Material
Collection of Samples
3.4.
3.4.
3SUMMARY
68
68
68
69
69
70
72
72
72
72
73
73
This proposal is an interdisciplinary initiative of
archaeologists and nuclear physicists to contribute to
the synchronisation of Eastern Mediterranean cultures by using 14C dating with Accelerator Mass Spectrometry (AMS). An improved absolute chronology
based on precise UC dating would lead to a better
understanding of the interactions between these cultures and would help to deepen our insight into the
rich diversity of the second millennium BC in the
eastern Mediterranean. The UC dating will be performed at the Vienna Environmental Research Accelerator (VERA), a new centre for AMS at the Institute
for Radiumforschung und Kernphysik of the University of Vienna, which came into operation in 1996.
With the help of this facility it will be possible to
obtain better UC dates than in many old measured
samples from Egypt and other mediterranean countries do exist, by coming to an accuracy of 5%o, that
means a date +/- 50 years.
Within this project it will be proposed to perform
a certain amount (at least 200) of UC analyses of
samples from interesting sites. The main problem in
the synchronisation of these cultures lies in a controversy about absolute chronology that has been going
on since the early '70s. The main focus of interest has
been the date of the eruption of the volcano of
Thera. With means of historical dating it occurred in
the 15th century BC. With Natural Science it is dated
into the 17 th century BC. Thus it has an impact on
the absolute chronology of Egypt and all Mediterranean cultures.
14
C DATING WITH ACCELERATOR MASS SPECTROMETRY
2.1. 14C dating
Radiocarbon dating allows one to determine the age
of carbon-containing objects by using the radioactive
decay of 14C (t J/2 = 5730 a) as a clock. To this end the
initial 14C content must be known and the present one
must be measured. Radiocarbon dating has been
enormously useful for archaeology in the Holocene,
notwithstanding the ongoing debate about the precision of calibrated age determination, which gives the
actual calendar date.
After the invention of radiocarbon dating by
WlLLARD LIBBY in 1947, the I4C content was measured for thirty years by low-level beta counting
methods. Because of the long half-life, counting the
infrequent beta decays of 14C is a very inefficient way
of detecting it. The advent of accelerator mass spectrometry (AMS) in 1977 has revolutionised the field
by being capable of measuring the I 4 G content
through an isotope ratio measurement (14C/12C) at the
extremely low level of 1012 to 10"'''. Compared to beta
counting, the direct atom counting method of AMS
has increased the efficiency of 14C detection by a very
large factor (103). Therefore, the sample size can be
reduced by a factor of 1000 (1 mg carbon instead of
1 g), and the measuring time by a factor of 100 (30
minutes instead of 2 days). As a result. AMS became
an extremely valuable tool for archaeology whenever
limited amount of material is available and/or a large
number of samples have to be measured. Although
great strides towards improving the precision of AMS
measurements have been made, it is probably fair to
say that the highest precision (-0.25%, corresponding to an age uncertainty of ± 20 a) is still achieved
with beta counting. Several AMS facilities "routinely"
reach 0.5%, and a few manage to do even better. Due
to steadily increasing computerisation of AMS, the
much larger instrumental complexity as compared to
beta counting can be gradually offset. It is therefore
expected that AMS measurements will eventually
reach the same precision as beta-counting.
4
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
In the context of the present project, the precision of calibrated age determination is important,
which has to be clearly distinguished from the uncalibrated age, the so-called radiocarbon age. While the
uncertainty of the radiocarbon age is essentially
determined by the precision of the 14C measurement,
and is calculated by assuming the same initial 14C
content for all times, the absolute age depends on the
actual 14C content in nature. It is well known by now
that there exist considerable variations of the 14CO2
content in the atmosphere, the source of all radiocarbon in the biosphere. Fortunately, these variations
are precisely known for the past 11000 years through
the record of 14C in tree-rings. Dendrochronology, the
science of tree-ring dating, provides an absolute time
scale for the 140 content in the atmosphere, which
allows one to convert the uncalibrated radiocarbon
age to a calibrated true age1. It is, however, a fact of
nature that the fluctuations of I4C sometimes lead to
an uncertainty of the calibrated age which is considerably larger than the one of the radiocarbon age. On
the other hand, there are smooth sections of the calibration curve, which do allow a calibrated age determination with high precision. In cases where those
sections coincide with periods of particular interest
in archaeology, a valid comparison of radiocarbon
dates with dates obtained from other methods (e.g.
historical time scales) can be made. For a meaningful
comparison it is, however, very important that the
uncertainties of all methods being compared are carefully evaluated. Given this caveat., radiocarbon dating
should be well capable of contributing significantly
towards an improved synchronisation of events in the
periods of interest of the present proposal.
2.2 VERA
The Vienna Environmental Research Accelerator
Radiocarbon measurements of selected samples
(supervised by PETER STAULER from the Prähistorische Abteilung, Naturhistorisches Museum Wien)
1
2
S TUIVER M.. L ONG A., K RA R. S., eds.,(1993), Calibration
1993, Radiocarbon 35/1, 1 244. - TAYLOR R. E., STUIVER M.,
REIMER P. J, (1996). Development and extension of the cal
ibration of the radiocarbon time scale: archaeological appli
cations, Quatern. Sei. Rev. Vol. 15, pp. 655-668.
K UTSCHERA W., C OLLOX P., F RIEDMANN H., G OLSER R..
H ILLE P., P RILLER A.. R OM W.. S TEIER P., T AGESEN S.,
WALLNER A., WILD E., WLXKLER G., (1997), VERA: A new
AMS facility in Vienna, Nucl. Instr. Meth. B 123, 41-50. PRILLRR A. GOLSER R.. HILLE P., KUTSCHERA W., Ron W.,
STEIER P., WALLNER A, WILD E. (1997), First performance
tests of VERA. Nucl. Instr. Meth. B 123, 193-198.
69
will be performed at the new AMS facility in Vienna
called VERA (Vienna Environmental Research
Accelerator). This facility became operational in
1996 and is operated by the Institut für Radiumforschung und Kernphysik of the University of Vienna. One of the major programmes at VERA is radiocarbon dating of milligram-size samples for various
projects". Although still a young facility, an overall
uncertainty of 0.5% (±40 years) for radiocarbon age
measurements of archaeological samples in the age
range of 1000 to 6000 years BP (before present) has
already been achieved3.
The VERA facility is operated by a staff of three
full-time Ph.D. physicists, ALFRED PRILLER (accelerator). ROBERT GOLSER (experiments) and EVA WILD
(sample preparation), and supported by a technical
staff of five people and several graduate students
working on various AMS-related projects. Other staff
people of the Institut für Radiumforschung und Kernphysik are part-time involved in AMS work at VERA.
The facility is headed by WALTER KUTSCHERA, who
has been involved in AMS for almost twenty years.
In order to further improve the overall precision of
radiocarbon age determinations with VERA, a highprecision stable mass spectrometer coupled to an element analyser will be purchased through project Nr.
PI2253, approved by the Fonds zur Förderung der wissenschaftlichen Forschung of Austria on 10/11 March
1997. This mass spectrometer will allow measurements of the 13C/12C stable carbon isotope ratio, the socalled 813C value, with a precision of about 0.()!%<>. In
addition to correcting the I4C/'~C ratios measured
with VERA for mass fractionation, necessary to
obtain the true age of the sample, high-precision 13C
values are also useful to identify the sample material
through their particular isotope signature. For example, so-called C3-plants (95% of all plants on earth)
acquire 813C values between —31 and -24%o, whereas
C4-plants (e.g. sugar cane, maize) have 8I8C values
between-15 and-10%o4.
3
4
WILD E., GOLSER R., HILLE P., KUTSCHERA W, PRILLER A..
PUCHEGGER S., ROM W, STEIER P., VVCUDILIK W.. (1998).
First results from archaeological and forensic studies at the
Vienna Environmental Research Accelerator, Radiocarbon,
in press.
SCHMIDT H.-L., BUTZENLECHXER M., ROSSMAXX A.,
S C H WAR Z S., K EXEL H., K EM P E K., (1993), Inter- and
intramolecular isotope correlations in organic compounds as
a criterion for authenticity identification and origin assign
ment, Z. Lebensm. Unters. Forsch. 196, 105-110.
70
Walter Kutschera and Peter Stadler
VERA should be quite capable of performing the
radiocarbon dating tasks expected from the present
project. We envision high-precision measurements of
approximately 200 relevant samples.
W.K.
ARCHAEOLOGICAL ASPECTS
3.1 Status of the Absolute Chronology of Civilisations in the Eastern Mediterranean in the Second
Millennium BC
Absolute dating is most important for the synchronisation of ancient cultures. The project aims to evaluate the already existing links between these cultures
and to establish interregional datumlines. In particular, emphasis will be put on attempting to solve the
apparent differences in certain critical dates obtained
by the Humanities and Natural Science.
One of the most debated questions in absolute
chronology is foeussed on the exact dating of the volcanic eruption of Thera-Santorini, which Historians
and Egyptologists date into the 16th or 15th century
BC. while the results of research in Natural Science
with an increasing number of available methods
point to the 17th century BC. Table 1 shows representative results for this event promoted by different
archaeologists. Depending on the dating method
adopted by the respective archaeologists, they arrive
at different dates. The first two dates interpret dendrochronologically dated growth anomalies in tree
rings as being the result of a volcanic eruption. The
other dates are obtained by linking stratigraphic evidence to the Egyptian historical chronology.
The various dating methods of Natural Science
deliver similar results: Ice drill examinations suggest
a date of the eruption of Thera at 1645 BC ± 20 y.6
HAMMER, C.U., CLAUSEN, H.B., FRIEDRICH, W. L., TAUBER,
H. (1987), The Minoan eruption of Santorini in Greece
dated to 1645 BC? Nature 328. 517-519. BAILLIE, M. G. L
(1998), Evidence for Climatic Deterioration in the 12th and the
17th centuries BC. In: HANSEL B., Man and environment in
European Bronze Age. 49-55. LAMARCHE V. C,
HlRSCHBOECK, K. K. (1984), Frost rings in trees as record
of major volcanic eruptions. Nature 307, 121-126.
MANNING S., WENINGER B. (1992), A light in the dark:
archaeological wiggle matching and the absolute chronology of the Aegean Late Bronze Age. Antiquity 66. 636 -63.
- WOELFLI W. (1989), AMS Radiocarbon Dating of Middle
and Late Bronze Age Settlements in Akrotiri prior to Santorini
(Thera) Eruption. Paper presented at the third Int. Congress on "Thera and the Aegean World III", Santorini,
However, currently it is discussed that dates from ice
cores, which supply year rings of ice growth and acid
layers corresponding to SO2/SO3 emission from volcano eruptions, are not as accurate as dendrochronology. Their count of years may be exact to only ± 1 %.
thus the uncertainty would be about ± 40 y.B
The dendrochronological results which are based
on the investigation of frost rings in trees as records
of major volcanic eruptions7 lead to the year 1627
BC. In addition, various results of 14C dating seem to
support the assumption of the 17th century BC for
the eruption.
In the following, an assessment of the 14C dating
situation based on available information is presented.
Table 28 summarises relevant dates extracted from
our 14C database, currently containing 30000 dates.9
Tables 3 and 4 and figures 1 to 8 present the evaluation of these 14C dates.
In table 3 well-identifiable events are dated. For
example, destruction layers are the result of a particular event. We have such destruction layers in
Akrotiri, which are the result of the volcano eruption. But we have also other destruction layers in
Late Minoan III in the palaces from Knossos and also
on other Helladic sites in Late Helladic III, which are
the results of human activity.
One of the problems in evaluating the data of
table 2 is the fact that the destruction layers which
are in Thera contain also much older samples."1 Thus
the so-called %2-test, which checks whether the scatter of dates correspond to a Gaussian distribution,
fails to prove that all the data came from one single
event. Although figure 1 shows that the lo (68.2%
confidence) range of the calibrated dates falls
between 1685 BC and 1620 BC, the failing of the %2test proves that the dates originate from more than
Greece, 3-9 September 1989, unpublished. I wish to thank
Prof. WOEFLl for his permission to use his unpublished data
here. - FRIEDRICH W. L., WAGNER P., TAUBER H. (1980J,
Radiocarbon dated plant remains from the Akrotiri excavation
on Santorini, Greece. In: H ARDY I). A., Thera and the
Aegean World, II, 188-196. London. - H AMMER , C. U.,
CLAUSEN, H. B., FRIEDRICH, W. L., TAUBER H. (1987), The
Minoan eruption of Santorini in Greece dated to 1645 BC?
Nature 328, 517-519. - HOUSLEY R, HEDGES R. E. M., LAW I.
A., BRONK C. R. (1990), Radiocarbon dating by AMS of the
destruction of Akrotiri. In: HARDY D. A. (Ed.). Thera and the
Aegean World, III, 207-215, London.
" This database was collected in another project: FRIESINQER
H., KUTSCHERA W., W'ILD E., STADLER P. (1997). Absolute
Chronology for Early Civilisations in Austria and Central
Europe using MC Dating with Accelerator Mass Spectrometry.
I4
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
71
one event. However, if we reduce the data by all samples with a a < 100 y and all those whose origin from
the destruction layer cannot be proved, we get a
smaller dataset of 25 samples. For them the x2-test is
valid (see fig. 2). But now we obtain - as a result of
the calibration curve - two ranges, the first from
1680 BC to 1670 BC and the second from 1620 BC to
1520 BC. That means in other words that measuring
a lot of new samples from the destruction layer of
Thera will not result in finding out which range is the
true one. Thus 14C dating - because of the shape of
the calibration curve at that time - is not capable to
distinguish between the high and low chronology for
the Thera event. We therefore conclude from this
analysis that it is not worthwhile, to concentrate on
measurements from this event only.
Another event, the destruction of the palaces of
Knossos, was formerly connected with the Thera
event. But as archaeological chronology demonstrates, these were not contemporary. Late Minoan IA
is far away from Late Minoan III. and so is Late Helladic I I I . The 14C dates of table 3 and figures 3 and 4
also support this point. They also suggest that the
destructions in Crete took place earlier than at the
Helladic sites. But we do have only two dates from
the Late Minoan 111 destruction, so after some new
analyses the picture might change. We therefore propose to date samples from other destruction layers in
the whole Aegean.
Table 4 and figures 5 to 8 present the group calibrations of the periods Late Minoan IA, II, III and
Late Helladic III. The obtained time ranges follow
each other in the way they should, but overlap very
much, which might be due to early UC measurements
and not too perfect sample selection.
As the calibration of the UC dating method is
based on the time scale provided by dendrochronology there is an interdependence between the results
of these two dating methods. The commonly used
dendrochronology is based on trees grown in North
America and Europe (Germany and Ireland). This
raised objections to the application of this chrono-
logy for the Eastern Mediterranean". But the dendrochronology presently developed on Anatolian
trees seems to deliver results exactly matching other
dendrochronologies, supporting a date for the Thera
eruption within the 17th century. At Porsuk, 840 km
east of Thera, some very important tree ring samples were found. They have been combined with others from Anatolia to form a floating sequence of
1503 years. This sequence was absolutely dated with
18 high-precision 14C dates by "wiggle-matching"
these dates to the standard calibration curve resulting in a dendrochronology beginning at 2233 BC and
running to 731 BC (+76 y/-22 y). Ring no. 854 in this
sequence showed a remarkable growth anomaly.
This ring was not like a frost ring in the North American dendrochronology und thus very thin, but
attracted the attention because of its enhanced
growth. KUNIHOLM et al. l2 argue that this growth
may in fact be caused by the Thera ash cloud leading
to heavy rain fall in Anatolia, whereas it led to frost
rings in North America. Within the time range
obtained by wiggle matching, ring no. 854 can be
assigned to the year 1627 BC, thus fixing the Anatolian dendrochronology to 2220-718 BC.
BlETAK13 discovered in Lower Egypt in the Hyksos settlement of Tell el-l)abca pumice presumably
deriving from the great eruption of Thera. Thus the
advocates of the conventional (lower) chronology
have taken great comfort from the discovery of this
pumice in strata which follow those of the late Hyksos palace recently unearthed at this site. Deposits
associated with that palace contained fragments of
fresco paintings of Minoan character closely resembling some of those found in Thera and dating from
the period immediately before the great eruption
(LMIA). Due to stratigraphical reasons these layers
can be dated earliest to the beginning of the 18th
dynasty, this means after the Cambridge Ancient
History Record (CAHR) about 1550 BC.
So the dating of the Thera eruption - from the
point of view of the Historians - is closely connected
to the Egyptian chronology and to the CAHR. There
"' It is not always clear, however, wether this is due to the "old
wood" problem, or to samples whose context with the
destruction is not assured.
1
RoHL D.. (1996), Addendum C: Datierung nach der Radio
carbonmethode. In: Pharaonen und Propheten. Das Alte
Testament auf dem Prüfstand, Droemer Knaur, 451-458.
12
KüNIHOLM P.I. et al. (1996), Anatolian tree rings and the
absolute chronology of the Eastern Mediterranean,
2220-718 BC, Nature 381. 780-782.
BlETAK M. (1995), Connections between Egypt and the
Minoan World: New Results from Tell el-Dabca. In: DAVIES W.
V., SCHOFIELI) L. (Ed.). Egypt, the Aegean and the Levant
- Interconnections in the second Millennium. Colloquium
at the British Museum in July 1992. 19-28.
13
Walter Kutschera and Peter Stadler
72
are three floating relative chronologies with absolute
duration: One for the Old Kingdom, one for the Middle Kingdom and one for the New Kingdom. For each
of them the list of kings with the time span of their
rule is known.
The apparent discrepancy between the historical
date of the Thera eruption and the one suggested by
various dating methods within the realm of Natural
Science is clearly disturbing. Thus, one of the main
interests of our project is to date relevant samples
with AMS under special precaution for the sample
selection, hopefully leading to an improved understanding of this critical time period.
In order not to merely replicate the current work
of other researchers, we list below those efforts.
3.2 Other currently ongoing projects
P. KUNlHOLMs Aegean Dendrochronology Project,
as cited already above.14
S. MANNING, The Aegean-East Mediterranean
Radiocarbon Calibration Project.1'
This project will investigate whether significant
differences of l40 content in the atmosphere existed
in different regions such as Germany and the Aegean
by measuring synchronised tree rings from the two
regions.
E. ZANGGER "Thera Dating". In this project many
samples of different stratigraphies from Middle
Minoan to Late Minoan from sites in the Aegean will
be dated. The samples will be collected not too near
to Thera to avoid the possibility that volcanic activity influenced the UC content in the growing trees."'
HOUSLEY investigated a possible contaminant1'
which, however, could make samples older by only 25
years.
W. WOELFLI18 is currently in the final stage of a
project, which dated many samples from Egypt,
from the Old Kingdom to the New Kingdom.
WOELPLI19 showed earlier that calibrated 14C dates of
the Old Kingdom are on an average 375 years older
than obtained from CAHR.
14
15
16
17
http://www.arts.cornell.edu/dendro.
http://www.arts.cornell.edu/dendro/97news/97adplet.html
ZANGGER E. (1998), Personal communication by e-mail.
H OUSLEY R, H EDGES R. E. M., L AW I. A., B RONK C. R.
(1990), Radiocarbon dating by AMS of the destruction of
Akrotiri. In: H ARDY D. A. (Ed.), Thera and the Aegean
World, III, 207-215, London.
3.3 Directions for our project
We propose the following directions:
Measurement of samples from destruction layers from
the whole Eastern Mediterranean from EM or MM to
LM. For every layer at least 5 samples should be measured, with the preference to short-lived material.
Measurement of samples from stratigraphies obtained
from, modern excavations. Also here, it would be necessary to date 5 samples per stratum, again of short-lived
material.
A special effort should be made to find carbonised trees
from Thera, which have lived till the event and were
killed by it. If they contain 200 tree rings, about 20 samples could be analysed for 14C. With wiggle matching it
should then be possible to date the Thera event. On the
other hand, it should also be possible to measure the
width of the tree rings and to find the exact dendrochronological position.
3.4 Selection of Samples
Among a variety of selection criteria for samples, two
are particularly important: First, the samples should
have a good archaeological context, which means
that their position in the context should be known
and the stratigraphy should be clear. Second, these
strata or contexts should also contain well-defined
and archaeologically datable remains.
3.4.1 Selection by Time
Dependent on the shape of the calibration curve not
all segments are equally well suited for I4C dating. To
show the problems, in figure 9 and 10 two overlapping
sections of the calibration curve are presented. The
first ranges from 2500 BC to 1500 BO and the second
from 2000 BC to 1000 BC.
The samples should only be taken from archaeological contexts belonging to segments of the calibration curve where it is steep and unambiguous. These
segments are to be considered as "secure" for the
absolute dating, obtaining a minimum of uncertainty.
WoELFLI W. (1998). Personal communication by e-mail.
WoELFLI W.. (1994), Archäologie mit dem Schwerionenbeschleuniger. Physik in unserer Zeit 25/2, 58-66.
especially with his fig. 10.
14
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
The VERA facility is capable for high precision
(0.5%) measurements. Therefore the multiple measurement of samples selected from "secure" segments
of the calibration curve would reduce the uncertainty
of the results to a minimum.
The following time segments in the first half of the
second millennium BC are at our disposal for high precision measurements: 1960-1880 BC, 1660-1620 BC
and 1440-1420 BC. the last segment is really too short.
Furthermore, for samples not matching the
"secure" segments one may also achieve an absolute
age assignment by wiggle matching of the corresponding sections of the calibration curve, if the
samples come from trees (with more than 80 tree
rings) or from stratigraphies.
rial. Especially in contexts, which allow relative and
absolute dating like in Egypt this selection is
absolutely necessary. Additionally, there is the possibility to use bones of short-lived animals for dating.
as the VERA facility is experienced in bone dating.""
3.4.2 Selection by Material
Table 1: Dating of the Thera eruption"1
Samples of charcoal have to be selected carefully
because they may raise the general problems of old
wood. If the find originates from wood which was
already old when it was burnt the date delivered by
14
C dating could be too old. Therefore, in this project
the focus is on the dating of short-lived samples - as
far as available - such as burnt seeds or similar mate-
Archaeologist
Table 2:
14
Period
Lab.
#
LHIII
LH1I1
LH111
OxA
P
P
LHIII
LHIII
LHIII
LHIII
LHIII
LHIII
LHIII
LHIII
P
P
St
211
21
22
The collection of the samples from Egypt and different regions of the Aegean will be done by the co-operators of the project. It is clearly important that any
collection of samples is performed with utmost attention to the archaeological context and with great care
for an uncontaminated preservation of the sample
material.
P.S.
Date (BC)
Niemeier22
Betancourt28
1627
1(527
Driessen/Mc Donald"4
Bietak*'
Warren/Cadogarr"
1550/1530
1550/1500
1550/1480
C Data used in this study
st
I
I
I
I
3.4.3 Collection of Samples
Site
Destr.
146
1454
1455
Mycenae
Mycenae
Mycenae
d
d
d
Charred wheat
Charcoal
Charcoal
1456
1457
1267
1549
6079
6081
6082
6082
Mycenae
Mycenae
Midea
Midea
Nichoria
Nichoria
Nichoria
Nichoria
d
d
d
d
Charcoal
Charcoal
Carbonised figs
Carbonised figs
Charcoal?
Charcoal ?
Charcoal?
Charcoal?
Material
WILD, E., GOLSER, R.: HILLE, P., KUTSCHERA, W., PRILLER,
A., ROM, W., STETER, P., 14C dating results from VERA, contribution to the 16th International Radiocarbon Conference
in Groningen, 16-20 June 1997, Proceedings to be published
in Radiocarbon.
Abbreviations used in Tables 1—4:
LMIA
=
Late Minoan IA
LMII
=
Late Minoan II
LMIII
=
Late Minoan III
LHIII
=
Late Helladic 111
N IEMEIER , W. D., (1995) Erläuterungen zur absoluten
Chronologie und zu den Kulturphasen in Zentralkreta.
i*C Age
Sigma
Literature
2970
2873
2974
130
57
49
Manning 1992
Manning 1992
Manning 1992
3035
2948
2935
3005
2215
3230
2990
2990
65
49
70
100
90
90
90
90
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
23
24
23
26
comment
BETANCOURT, P. P. (1988), Dating the Aegean Late Bronze
Age with Radiocarbon. Archeometry 29, 45-49.
DRIESSEN, J., MACDONALD, C. F. (1995), The troubled island,
Minoan Crete and the Santorini Eruption.
B IETAK . M. (1995), Connections between Egypt and the
Minoan World: New Results from Tell el-Dab'a. In: D AVIES .
W. V, SCHOFIELD, L (Ed.), Egypt, the Aegean and the Levant - Interconnections in the second Millennium BC, Colloquium at the British Museum in July 1992, 19—28.
MYERS, J.W, MYERS,E., in: OADOGAN,G., WARREN, P. et. al.
(Ed.) (1992). The Aerial Atlas of Ancient Crete, 33.
Walter Kutschera and Peter Stadler
74
Period
Lab.
#
Site
LHIII
LHIII
LHIII
LHIII
LHIII
LHIII
LHIIT
LHIII
LHIII
LHIII
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LJ
LJ
P
P
P
P
P
P
P
P
ETH
ETH
ETH
ETH
ETH
ETH
ETH
ETH
ETH
ETH
ETH
K
K
K
OxA
Ox A
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
OxA
1883
3043
326
328
329
330
332
337
340
341
3313
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3227
3228
4255
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1686
1687
1688
1689
1690
1691
Lefkandi
Lefkandi
Pvlos
Pylos
Pylos
Pvlos
Pvlos
Pylos
Pvlos
Pvlos
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
d
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
OxA
OxA
P
P
P
P
P
P
P
P
P
1692
1693
1599
1619
1885
1888
1889
1892
1894
1895
2559
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
d
d
d
d
d
d
d
d
d
d
d
Destr. Material
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Seed
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Charcoal
Seed
Seed
i*C Age Sigma
Literature
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Legumes
Legumes
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
3070
3070
3450
3220
3260
3360
3140
3030
3320
3010
3710
3610
3434
3604
3350
3499
3390
3349
3420
3437
3453
3400
3340
3380
3335
3460
3395
3465
3390
3340
3280
3245
3415
3240
3400
3385
3280
3480
3270
3340
3320
80
60
65
64
63
50
61
61
57
56
58
51
48
51
50
42
50
53
56
54
52
70
55
60
60
80
65
65
65
65
65
65
70
60
60
90
60
70
60
110
60
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Wölfli 1989
Friedrich, W., 1980
Hammer 1987
Hammer 1987
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley. R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al.. 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley, R. et al., 1990
Housley. R. et al., 1990
Housley. R. et al., 1990
Short 1.
Short 1.
Charcoal, undersized
Charcoal, undersized
Seeds
Shrubs
Shrubs
Shrubs
Shrubs
Shrubs
Grains
3325
3420
3094
2972
3246
3128
3298
3331
3307
3324
3380
90
60
150
71
48
50
52
52
65
51
70
Housley, R. et al., 1990
Housley. R. et al., 1990
Michael, H., 1978
Michael. H., 1978
Hammer 1987
Michael, H., 1978
Hammer 1987
Hammer 1987
Hammer 1987
Hammer 1987
Hammer 1987
comment
contaminant
residue
contaminant
residue
contaminant
residue
residue
contaminant
75
"C Dating for Absolute Chronology of Eastern Mediterranean Cultures
Period
Lab.
#
Site
Destr.
LMIA
T.MIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
P
P
P
P
P
P
P
P
P
P
P
P
K
K
K
K
L
P
P
2560
2561
2562
2563
2564
2565
2566
2791
2792
2793
2794
2795
3228
4255
5352
5353
362
1401
1697
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
d
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Phira
Phira
Akrotiri Meghalochori
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
P
P
P
P
P
P
P
P
P
P
P
1885
1889
1890
1892
1894
1895
2559
2559
2561
2562
2564
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
LMIA
LMIA
LMIA
LMIA
LMIA
LMIA
LMII
LMI1
LMII
LMII
LMII
LMII
LMII
LMII
LMII
LMII
LMII
LMII
LMII
LMIII
LMIII
P
P
P
P
P
P
P
Hv
Hv
Hv
OxA
OxA
OxA
OxA
P
P
P
P
P
P
P
2565
2565
2566
2791
2794
2795
2045
??
??
??
2096
2097
2097
2098
1357
1358
2046
2047
2048
1359
2441
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Akrotiri
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Knossos
Material
Grains
Grains
OD, undersized
OD, undersized
OD. undersized
Grains
OD, undersized
Short 1.
Short 1.
Short 1.
Short 1.
Short 1.
Charcoal
Short 1.
Charcoal
d
d
Charcoal
Charcoal
Charcoal
Charcoal
Charred barley
Charcoal
Seed
Seed
Charcoal
Charcoal
charred resin
Charcoal
Charcoal
Charcoal
Charcoal
"C Age
Sigma
Literature
3990
3810
2890
3180
3050
3320
2836
3340
3670
3300
3180
3380
3340
3380
3310
3430
3370
3406
3072
70
60
190
190
190
60
180
60
180
140
50
170
55
60
65
90
100
43
57
Michael. H.. 1978
Michael, H., 1978
Michael, H., 1978
Michael, H., 1978
Michael, H., 1978
Hammer 1987
Michael, H., 1978
Hammer 1987
Hammer 1987
Hammer 1987
Hammer 1987
Hammer 1987
Friedrich, W., 1980
Friedrich, W. etal, 1990
Friedrich, W. etal., 1990
Friedrich, W. etal., 1990
Michael, H., 1978
Michael, H., 1978
Michael, H., 1978
3246
3298
3343
3331
3307
3324
3370
3380
3800
2890
3050
48
52
62
52
65
51
70
70
50
190
190
Michael, H.. 1978
Michael, H., 1978
Michael, H.. 1978
Michael, H., 1978
Michael. H.. 1978
Michael. H.. 1978
Houslev, R. etal., 1990
Michael, H., 1978
Housley, R. etal., 1990
Housley. R. et al., 1990
Housley, R. etal., 1990
3310
3320
2830
3340
3180
3380
3320
3300
3250
3365
3070
3190
3190
3220
3096
3033
3820
3930
3460
3226
3060
60
60
180
60
50
170
50
65
95
50
70
65
65
65
69
68
50
70
50
43
60
Housley, R. etal., 1990
Michael, H., 1978
Housley R, et al., 1990
Houslev, R, etal., 1990
Housley, R. et al., 1990
Housley R. et al., 1990
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Housley, R. etal., 1990
Housley, R. etal., 1990
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
Manning 1992
comment
Walter Kutschera and Peter Stadler
76
Tab. 3: Combined Calibrations for an event
Data use
Period/Event
# of dates
Combined Result,
i*C Age (BP)
Calibrated Ranges
for 68,2% (BC)
X2-test
Fig.
All data
LMIA destruction
44
3354 ± 10
1685-1620
fails
1
data reduced
All data
All data
LMIA destruction
LM11I destruction
LHIII destruction
25
2
7
3316 ± 11
3169 ± 34
2955 ± 23
1680-1670. 1620-1520
1495-1475. 1460-1405
1260-1240.1220-1120
valid
fails
valid
2
3
4
Tab. 4: Group Calibrations for periods
Period
LMIA
LMII
LM11I
LHIII
# of dates
59
12
2
20
Calibrated Ranges for 68,2% (BC)
1880 1840(1820-1450)
1740-1260
1530-1260
1600-1050
Fig.
5
6
7
8
Fig. 1 Calibration of 14C Ages with the program OxCal
'http//umts.ox.ac.uk/departments/rlaha/oxcal/oxcal_h.html' to obtain absolute ages (calibrated date). Combined results of 44
individual dates from the destruction layer of Akrotiri. All results were obtained by using the intcal98 calibration curve. STOVER,
M. et al. 1998, INTCAL98 Radiocarbon Age Calibration, 24000-0 cal BP. Radiocarbon 40 (3). 1041-1083.
U
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
Fig. 2 Combination calibration with reduced data set of 25 individual dates from the destruction layer of Akrotiri (see text)
Fig. 3 Combined calibration with two samples of LM III destruction layer from Palace of Knossos (Crete)
77
78
Walter Kutschera and Peter Stadler
Fig. 4 Combined calibration of seven samples of LH III destrueion layer from different sites
Fig. 5 Group calibration of 59 samples from LM IA
14
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
Fig. 6 Group calibration of 12 samples from LM II
Fig. 7 Group calibration with two samples from LM III
79
80
Walter Kutschera and Peter Stadler
Fig. 8 Group calibration of 20 samples from LH III
Fig. 9 Calibration curve from 2500 BC to 1500 BC
14
C Dating for Absolute Chronology of Eastern Mediterranean Cultures
Fig. 10 Calibration curve from 2000 BC to 1000 BC
Fig. 11 Other currently ongoing projects
Fig. 12 Directions for this projekt
81