3.5. the absolute chronology of Egypt and all Mediterranean

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2 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 C dating with Accelerator Mass Spectrometry U C dating VERA-The Vienna Environmental 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 73 SUMMARY This proposal is an interdisciplinary initiative of archaeologists and nuclear physicists to contribute to the synchronisation of Eastern Mediterranean cultures by using 14 C dating with Accelerator Mass Spectrometry (AMS). An improved absolute chronology based on precise U C 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 U C 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 With the help of this facility it will be possible to obtain better U C 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 U C 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 15 th 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 C dating Radiocarbon dating allows one to determine the age of carbon-containing objects by using the radioactive decay of 14 C (t J/2 = 5730 a) as a clock. To this end the initial 14 C 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 I4 C content was measured for thirty years by low-level beta counting methods. Because of the long half-life, counting the infrequent beta decays of 14 C 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 I4 G content through an isotope ratio measurement ( 14 C/ 12 C) at the extremely low level of to 10"'''. Compared to beta counting, the direct atom counting method of AMS has increased the efficiency of 14 C detection by a very large factor (10 3 ). 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.

3 4 C Dating for Absolute Chronology of Eastern Mediterranean Cultures 69 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 14 C measurement, and is calculated by assuming the same initial 14 C content for all times, the absolute age depends on the actual 14 C content in nature. It is well known by now that there exist considerable variations of the 14 CO 2 content in the atmosphere, the source of all radiocarbon in the biosphere. Fortunately, these variations are precisely known for the past years through the record of 14 C in tree-rings. Dendrochronology, the science of tree-ring dating, provides an absolute time scale for the 14 0 content in the atmosphere, which allows one to convert the uncalibrated radiocarbon age to a calibrated true age 1. It is, however, a fact of nature that the fluctuations of I4 C 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) 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 achieved 3. 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 This mass spectrometer will allow measurements of the 13 C/ 12 C stable carbon isotope ratio, the socalled 8 13 C value, with a precision of about 0.()!%<>. In addition to correcting the I4 C/'~C ratios measured with VERA for mass fractionation, necessary to obtain the true age of the sample, high-precision 13 C values are also useful to identify the sample material through their particular isotope signature. For example, so-called C 3 -plants (95% of all plants on earth) acquire 8 13 C values between 31 and -24%o, whereas C 4 -plants (e.g. sugar cane, maize) have 8 I8 C values between-15 and-10%o STUIVER M.. LONG A., KRA R. S., eds.,(1993), Calibration 1993, Radiocarbon 35/1, 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 KUTSCHERA W., COLLOX P., FRIEDMANN H., GOLSER R.. HILLE P., PRILLER A.. ROM W.. STEIER P., TAGESEN S., WALLNER A., WILD E., WLXKLER G., (1997), VERA: A new AMS facility in Vienna, Nucl. Instr. Meth. B 123, 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, 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., SCHWARZ S., KEXEL H., KEMPE 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,

4 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 16 th or 15 th century BC. while the results of research in Natural Science with an increasing number of available methods point to the 17 th 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 However, currently it is discussed that dates from ice cores, which supply year rings of ice growth and acid layers corresponding to SO 2 /SO 3 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 eruptions 7 lead to the year 1627 BC. In addition, various results of 14 C dating seem to support the assumption of the 17 th century BC for the eruption. In the following, an assessment of the 14 C dating situation based on available information is presented. Table 2 8 summarises relevant dates extracted from our 14 C database, currently containing dates. 9 Tables 3 and 4 and figures 1 to 8 present the evaluation of these 14 C 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 % 2 - test proves that the dates originate from more than HAMMER, C.U., CLAUSEN, H.B., FRIEDRICH, W. L., TAUBER, H. (1987), The Minoan eruption of Santorini in Greece dated to 1645 BC? Nature BAILLIE, M. G. L (1998), Evidence for Climatic Deterioration in the 12 th and the 17 th centuries BC. In: HANSEL B., Man and environment in European Bronze Age LAMARCHE V. C, HlRSCHBOECK, K. K. (1984), Frost rings in trees as record of major volcanic eruptions. Nature 307, MANNING S., WENINGER B. (1992), A light in the dark: archaeological wiggle matching and the absolute chronology of the Aegean Late Bronze Age. Antiquity 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, 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: HARDY I). A., Thera and the Aegean World, II, London. - 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, 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, , 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 M C Dating with Accelerator Mass Spectrometry.

5 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 x 2 -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 14 C 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 III. The 14 C 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 U C measurements and not too perfect sample selection. As the calibration of the U C 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 17 th 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 14 C 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 BC. BlETAK 13 discovered in Lower Egypt in the Hyksos settlement of Tell el-l)ab c a 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 18 th 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, KüNIHOLM P.I. et al. (1996), Anatolian tree rings and the absolute chronology of the Eastern Mediterranean, BC, Nature BlETAK M. (1995), Connections between Egypt and the Minoan World: New Results from Tell el-dab c a. 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

6 72 Walter Kutschera and Peter Stadler 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 l4 0 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 U C content in the growing trees."' HOUSLEY investigated a possible contaminant 1 ' which, however, could make samples older by only 25 years. W. WOELFLI 18 is currently in the final stage of a project, which dated many samples from Egypt, from the Old Kingdom to the New Kingdom. WOELPLI 19 showed earlier that calibrated 14 C dates of the Old Kingdom are on an average 375 years older than obtained from CAHR. 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 14 C. 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 Selection by Time Dependent on the shape of the calibration curve not all segments are equally well suited for I4 C 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 ZANGGER E. (1998), Personal communication by . 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, , London. WoELFLI W. (1998). Personal communication by . WoELFLI W.. (1994), Archäologie mit dem Schwerionenbeschleuniger. Physik in unserer Zeit 25/2, especially with his fig. 10.

7 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: BC, BC and 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 Selection by Material 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- 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."" Collection of Samples 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. Table 1: Dating of the Thera eruption" 1 Archaeologist Date (BC) Niemeier Betancourt 28 1(527 Driessen/Mc Donald" /1530 Bietak*' 1550/1500 Warren/Cadogarr" 1550/1480 Table 2: 14 C Data used in this study Period Lab. # Site Destr. Material i*c Age Sigma Literature comment LHIII OxA 146 Mycenae d Charred wheat Manning 1992 LH1I1 P 1454 Mycenae d Charcoal Manning 1992 LH111 P 1455 Mycenae d Charcoal Manning 1992 LHIII P 1456 Mycenae d Charcoal Manning 1992 LHIII P 1457 Mycenae d Charcoal Manning 1992 LHIII St 1267 Midea d Carbonised figs Manning 1992 LHIII st 1549 Midea d Carbonised figs Manning 1992 LHIII I 6079 Nichoria Charcoal? Manning 1992 LHIII I 6081 Nichoria Charcoal? Manning 1992 LHIII I 6082 Nichoria Charcoal? Manning 1992 LHIII I 6082 Nichoria Charcoal? Manning WILD, E., GOLSER, R. : HILLE, P., KUTSCHERA, W., PRILLER, A., ROM, W., STETER, P., 14 C dating results from VERA, contribution to the 16 th International Radiocarbon Conference in Groningen, June 1997, Proceedings to be published in Radiocarbon. 21 Abbreviations used in Tables 1 4: LMIA = Late Minoan IA LMII = Late Minoan II LMIII = Late Minoan III LHIII = Late Helladic NIEMEIER, W. D., (1995) Erläuterungen zur absoluten Chronologie und zu den Kulturphasen in Zentralkreta. 23 BETANCOURT, P. P. (1988), Dating the Aegean Late Bronze Age with Radiocarbon. Archeometry 29, DRIESSEN, J., MACDONALD, C. F. (1995), The troubled island, Minoan Crete and the Santorini Eruption. 23 BIETAK. M. (1995), Connections between Egypt and the Minoan World: New Results from Tell el-dab'a. In: DAVIES. 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, MYERS, J.W, MYERS,E., in: OADOGAN,G., WARREN, P. et. al. (Ed.) (1992). The Aerial Atlas of Ancient Crete, 33.

8 74 Walter Kutschera and Peter Stadler Period Lab. # Site Destr. Material i*c Age Sigma Literature comment LHIII LJ 1883 Lefkandi Charcoal Manning 1992 LHIII LJ 3043 Lefkandi Charcoal Manning 1992 LHIII P 326 Pvlos Charcoal Manning 1992 LHIII P 328 Pylos Charcoal Manning 1992 LHIII P 329 Pylos Charcoal Manning 1992 LHIII P 330 Pvlos Charcoal Manning 1992 LHIIT P 332 Pvlos Charcoal Manning 1992 LHIII P 337 Pylos Charcoal Manning 1992 LHIII P 340 Pvlos Charcoal Manning 1992 LHIII P 341 Pvlos Charcoal Manning 1992 LMIA ETH 3313 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3315 Akrotiri d Seed Wölfli 1989 LMIA ETH 3316 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3317 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3318 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3319 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3320 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3321 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3322 Akrotiri d Charcoal Wölfli 1989 LMIA ETH 3323 Akrotiri d Seed Wölfli 1989 LMIA ETH 3324 Akrotiri d Seed Wölfli 1989 LMIA K 3227 Akrotiri d Friedrich, W., 1980 LMIA K 3228 Akrotiri d Short Hammer 1987 LMIA K 4255 Akrotiri d Short Hammer 1987 LMIA OxA 1548 Akrotiri d Short Housley, R. et al., 1990 LMIA Ox A 1549 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1550 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1551 Akrotiri d Short Housley. R. et al., 1990 LMIA OxA 1552 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1553 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1554 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1555 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1556 Akrotiri d Short Housley, R. et al., 1990 LMIA OxA 1557 Akrotiri d Legumes Housley, R. et al LMIA OxA 1558 Akrotiri d Legumes Housley, R. et al., 1990 LMIA OxA 1686 Akrotiri d Short Housley, R. et al., 1990 contaminant LMIA OxA 1687 Akrotiri d Short Housley, R. et al., 1990 residue LMIA OxA 1688 Akrotiri d Short Housley, R. et al., 1990 contaminant LMIA OxA 1689 Akrotiri d Short Housley, R. et al., 1990 residue LMIA OxA 1690 Akrotiri d Short Housley. R. et al., 1990 contaminant LMIA OxA 1691 Akrotiri d Short Housley. R. et al., 1990 residue LMIA OxA 1692 Akrotiri d Short Housley, R. et al., 1990 residue LMIA OxA 1693 Akrotiri d Short Housley. R. et al., 1990 contaminant LMIA P 1599 Akrotiri d Charcoal, undersized Michael, H., 1978 LMIA P 1619 Akrotiri d Charcoal, undersized Michael. H., 1978 LMIA P 1885 Akrotiri d Seeds Hammer 1987 LMIA P 1888 Akrotiri d Shrubs Michael, H., 1978 LMIA P 1889 Akrotiri d Shrubs Hammer 1987 LMIA P 1892 Akrotiri d Shrubs Hammer 1987 LMIA P 1894 Akrotiri d Shrubs Hammer 1987 LMIA P 1895 Akrotiri d Shrubs Hammer 1987 LMIA P 2559 Akrotiri d Grains Hammer 1987

9 "C Dating for Absolute Chronology of Eastern Mediterranean Cultures 75 Period Lab. # Site Destr. Material "C Age Sigma Literature comment LMIA P 2560 Akrotiri d Grains Michael. H T.MIA P 2561 Akrotiri d Grains Michael, H., 1978 LMIA P 2562 Akrotiri d OD, undersized Michael, H., 1978 LMIA P 2563 Akrotiri d OD, undersized Michael, H., 1978 LMIA P 2564 Akrotiri d OD. undersized Michael, H., 1978 LMIA P 2565 Akrotiri d Grains Hammer 1987 LMIA P 2566 Akrotiri d OD, undersized Michael, H., 1978 LMIA P 2791 Akrotiri d Short Hammer 1987 LMIA P 2792 Akrotiri d Short Hammer 1987 LMIA P 2793 Akrotiri d Short Hammer 1987 LMIA P 2794 Akrotiri d Short Hammer 1987 LMIA P 2795 Akrotiri d Short Hammer 1987 LMIA K 3228 Akrotiri Friedrich, W., 1980 LMIA K 4255 Akrotiri Friedrich, W. etal, 1990 LMIA K 5352 Akrotiri Friedrich, W. etal., 1990 LMIA K 5353 Akrotiri Friedrich, W. etal., 1990 LMIA L 362 Phira Michael, H., 1978 LMIA P 1401 Phira Charcoal Michael, H., 1978 LMIA P 1697 Akrotiri - Meghalochori Short Michael, H., 1978 LMIA P 1885 Akrotiri Michael, H LMIA P 1889 Akrotiri Michael, H., 1978 LMIA P 1890 Akrotiri Charcoal Michael, H LMIA P 1892 Akrotiri Michael, H., 1978 LMIA P 1894 Akrotiri Michael. H LMIA P 1895 Akrotiri Michael. H LMIA P 2559 Akrotiri Houslev, R. etal., 1990 LMIA P 2559 Akrotiri Michael, H., 1978 LMIA P 2561 Akrotiri Housley, R. etal., 1990 LMIA P 2562 Akrotiri Housley. R. et al., 1990 LMIA P 2564 Akrotiri Housley, R. etal., 1990 LMIA P 2565 Akrotiri Housley, R. etal., 1990 LMIA P 2565 Akrotiri Michael, H., 1978 LMIA P 2566 Akrotiri Housley R, et al., 1990 LMIA P 2791 Akrotiri Houslev, R, etal., 1990 LMIA P 2794 Akrotiri Housley, R. et al., 1990 LMIA P 2795 Akrotiri Housley R. et al., 1990 LMII P 2045 Knossos Charcoal Manning 1992 LMI1 Hv?? Knossos Charcoal Manning 1992 LMII Hv?? Knossos Charcoal Manning 1992 LMII Hv?? Knossos Charcoal Manning 1992 LMII OxA 2096 Knossos Charred barley Manning 1992 LMII OxA 2097 Knossos Charcoal Manning 1992 LMII OxA 2097 Knossos Seed Housley, R. etal., 1990 LMII OxA 2098 Knossos Seed Housley, R. etal., 1990 LMII P 1357 Knossos Charcoal Manning 1992 LMII P 1358 Knossos Charcoal Manning 1992 LMII P 2046 Knossos charred resin Manning 1992 LMII P 2047 Knossos Charcoal Manning 1992 LMII P 2048 Knossos Charcoal Manning 1992 LMIII P 1359 Knossos d Charcoal Manning 1992 LMIII P 2441 Knossos d Charcoal Manning 1992

10 76 Walter Kutschera and Peter Stadler 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 ± fails 1 data reduced LMIA destruction ± valid 2 All data LM11I destruction ± fails 3 All data LHIII destruction ± valid 4 Tab. 4: Group Calibrations for periods Period # of dates Calibrated Ranges for 68,2% (BC) Fig. LMIA ( ) 5 LMII LM11I LHIII Fig. 1 Calibration of 14 C 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, cal BP. Radiocarbon 40 (3)

11 U C Dating for Absolute Chronology of Eastern Mediterranean Cultures 77 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)

12 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

13 14 C Dating for Absolute Chronology of Eastern Mediterranean Cultures 79 Fig. 6 Group calibration of 12 samples from LM II Fig. 7 Group calibration with two samples from LM III

14 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

15 14 C Dating for Absolute Chronology of Eastern Mediterranean Cultures 81 Fig. 10 Calibration curve from 2000 BC to 1000 BC Fig. 11 Other currently ongoing projects Fig. 12 Directions for this projekt