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1

New methods of dating in archaeology

Dergachev V. A., Vasiliev S.

Geochronometria

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2004

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Vol. 23

39-43

EN

A modification of statistical method to determine the relative age of wood samples based on the analysis of dendroseries has been developed. The main difference of the method proposed here from the one used earlier lies in the fact that there is the possibility to match several samples simultaneously. Using the methods of statistical analysis, we have the possibility to ascertain what is reliability of determination of the relative age. Approaches used in our method are typical for regression analysis. The correlation coefficient between the analyzed sample and the group of matching samples (the comparison groups) serve as a measure concordance. It is so-called multiple correlation coefficient. The Fisher F-statistics is used to determine the significance of matching. The method is applied for cross-dating of wood samples of archaeological monuments in the Southern Siberia.

2

Some problems in the study of the chronology of the ancient nomadic cultures in Eurasia (9th - 3rd centuries BC)

Alekseev A. Yu., Bokovenko N. A., Boltrik Yu., Chugunov K. A., Cook G., Dergachev V. A., Kovaliukh N., Possnert G., Plicht J. van der, Scott E. M., Sementsov A., Skripkin V., Vasiliev S., Zaitseva G.

Geochronometria

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2002

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Vol. 21

143-150

EN

This research is focused on the chronological investigations of ancient nomads belonging to the Scythian cultures which occupied the steppe and forest-steppe zones of Eurasia during the 9 th -3 rd centuries BC. The 14 C dates for the pre-scythian and early scythian time in both Europe and Asia are presented and compared to their chronological position based on archaeological evidence. The first 14 C dates have been produced for the Scythian time monuments located in the Lower Volga River basin, Urals and Transurals regions. Their chronological positions are compared with the position of the monuments of Southern Siberia and Central Asia. It was shown that the nomadic cultures belonging to the Scythian culture began to exist over the wide territory of Eurasia from the 9 th -8 th centuries cal BC and there are some monuments which may be synchronous to the Arzhan royal barrow (the oldest monument known). A list of new 14 C dates and a map of the monuments are presented.

3

Tree-rings, "wiggle matching" and statistics in the chronological studies of Scythian age sites in Asia

Vasiliev S., Bokovenko N. A., Chugunov K. A., Dergachev V. A., Sementsov A., Sljusarenko Yu., Zaitseva G.

Geochronometria

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2001

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Vol. 20

61-68

EN

A new method of cross-dating of wood samples is suggested. Based on the classical methods of spectral estimating, it uses the average cross-spectral density as a function of relative position of series. This procedure being not sensitive to phase shifts in data may be instrumental for the cross-dating of samples originating from different areas. The method was tested on Scythian tombs located in Southern Siberia, Central Asia and Kazakhstan, with the emphasis on the "Royal" barrows which included well preserved wood structures. For well-preserved timber samples, the accuracy in relative age estimations can reach a single year. The wiggle matching method has been used for a reliable assessment of the calendar-scale time.

4

Nonlinear methods of analysis of data with gaps

Dergachev V. A., Makarenko N. G., Karimova L. N., Danilkina E. B.

Geochronometria

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2001

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Vol. 20

45-50

EN

Information on most of natural phenomena can be obtained from time series of direct and proxy data. The analysis of time series generated by natural dynamic systems is a key element in interpreting geophysical and climatic information. Unfortunately, most of available time series have gaps. When there are many gaps with irregular distribution, we do not have any statistical tools for repairing the data. We suggest some approach to solve this problem. It is based on modeling the missing data by small-dimensional manifolds and neural network technologies. In this approach we assume that data under consideration are a set of n-dimensional vectors, which are produced by dynamical system. These vectors model n-dimensional attractor in embedding space. Gaps in the vectors are represented as a linear manifold L of some dimension. The method idea is to model L by another small-dimensional manifold, e.g. a curve. Neural networks are used to find this manifold. We verify the method on real time series data: sunspot numbers, the radiocarbon content in tree rings, the 10Be in ice cores, the width of tree rings and so on.