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Mesolithic occupations and environments on the Island of Ikaria, Aegean, Greece

Sampson A., Kaczanowska M., Kozłowski J. K., Athanassas C., Bassiakos Y., Liritzis I., Laskaris N., Tsermegas I.

Folia Quaternaria

2012

nr 80

1--87

The most important Mesolithic site on the Island of Ikaria, Kerame 1, extends 80 m along the sloping edge of the cliff and is up to 40 m wide. The site is a sum of repeated sojourns of Mesolithic groups that had left behind concentrations of lithic artefacts, which were subsequently displaced by post-depositional agents, first of all by erosion. As a result, the site reveals now a large concentration of finds in Trenches E, C, and G. Moreover, post-depositional agents caused the destruction of permanent features such as the hearths associated with the various khsemenitsas, or — possibly — stone rings surrounding the dwelling structures. Only in trenches D, B and E the remains of a circular stone rings, probably around hearths, were registered. The lithic industry of Kerame 1 displays considerable similarity to the site of Maroulas on Kythnos; the techno-morphological differences are, probably, the effect of differing raw materials structure at Kerame 1 and at Maroulas. At Kerame 1, the distant interregional contacts and the influx of extralocal raw materials (documented by the flow of obsidian nodules from Melos and Yali) caused that production in a full cycle was carried out on-site. Thus, there was no specialization of lithic production, and unworked nodules of raw material were exploited in the particular social clusters in a full cycle, whose outcome were tools to be used by a given unit. Regretfully, because organic materials (also bones) have not been preserved we have no data to determine seasonality at Kerame l. Nevertheless, we can say with all certainty that Mesolithic groups visiting Kerame 1 were mobile, which is evidenced by the network of interregional contacts. The most noticeable similarity between Kerame 1 and Maroulas can be accounted for by the chronological closeness of the two sites. The AMS determinations from Maroulas concentrate in the first half of the 9th millenium cal. BC (Facorellis et a1. 2010). Similarly, the dates from obsidian dehydration from Kerame 1 (if their broad standard deviation is overlooked) correspond to the first half of the 9th millenium cal. BC.

Optical dating of a late quaternary sediment sequence from Sokli, Northern Finland

Alexanderson H., Eskola K. O., Helmens K. F.

Geochronometria

2008

Vol. 32

51-59

Interstadial and non-glacial stadial sediments collected in boreholes from Sokli in northeastern Finland have been dated by optically stimulated luminescence on quartz and feldspar grains. The quartz OSL ages follow stratigraphic order, with one exception, and support the litho- and biostratigraphical correlation with the NW European mainland climate-stratigraphy and the marine oxygen-isotope stages. Feldspar IRSL dates generally overestimate the age, probably due to incomplete bleaching. The data show that during the last glacial cycle north-eastern Finland was not glaciated until MIS 5b, around 90 ka. Interstadial conditions occurred around ∼94 ka (MIS 5c), ∼74-80 ka (MIS 5a) and 42-54 ka (MIS 3). The OSL ages have large standard errors mainly due to small sample sizes, relatively poor luminescence characteristics and uncertainties in dose-rate determinations.

Chronostratigraphy of the Vistulian glaciation on the Kujawy Moraine Plateau (Central Poland) based on lithostratigraphic research and OSL dating

Przegiętka K. R., Chruścińska A., Oczkowski H. L., Molewski P.

Geochronometria

2008

Vol. 32

69-77

The subject of the investigations presented here is fixing dilemmatic character (transgressive or recessive) of the Poznań phase of the Vistulian (Weichselian) Glaciation and answering the question about the possibility of lithostratigraphic separation of this phase from the Leszno phase in the region of so called Vistula lob. Here we present the outcomes of the research project carried out on a few tills exposures, which constitute the sedimentological record of the last ice sheet advance on the Kujawy Moraine Plateau. The absolute ages of 17 samples (collected from fluvial deposits uncovered in the geological logs) have been determined by means of the OSL method applying the single aliquots regenerative (SAR) dose protocol. The OSL data are analysed with regard to supposed bleaching conditions at the moment of the last transport and deposition of the material. In conclusion, some remarks on suitability of fluvial sands for OSL dating are made. In most of the investigated sites, there appears to exist only a single till level associated with the main stage of the Vistulian Glaciation. This fact and the results of OSL dating support the hypothesis, that the Poznań phase in Kujawy Moraine Plateau is not a distinct lithostratigraphic unit, but it is a recessive phase of the last glaciation.