A Nyíregyházi Jósa András Múzeum évkönyve 33-35. - 1990-1992 (Nyíregyháza, 1993)

Ede Hertelendi: Radiocarbon Age of a „Loboat” Discovered near Tiszabecs

Radiocarbon Age of a "Logboat" DiscoVerd near Tiszabecs EDE HERTELENDI Abstract: The age of a "logboat" possibly having been a part of a water-mill or used for transportation was determined by radiocarbon method. The age range in calendar years is 1404-1494 cal AD. Introduction A large "logboat" i.e. a boat made from a single oak tree trunk was discovered in 1990 near Tiszabecs in the riverbed of the Tisza. The length of the boat is 12 m with a breadth of 1,5 m. Its mass is approximately 3,5 x 10

3 kg. The boat was transported without conservation to the Józsa András Museum in Nyíregyháza. Sample preparation, measurement Tree rings from the outer parts were used for radiocarbon dating. First the wood was cleaned thoroughly with a brush to remove any visible contamination. It was then cut into small pieces which were placed into a hammer mill and the grain size was reduced to about 500 urn. This was then treated in the normal manner with dilute HCl then sodium hydroxide to remove any carbonate and humic or fulvic substances. The traces of sodium hydroxide were removed by diluted HCl. The purified wood was dried and combusted to CO2. The carbon content of CO2 was converted to methane (CSONGOR—SZABÓHERTELENDI

1982.). The activity measurement was carried out using proportional counters (HERTELENDI et al. 1989.). The age (t) expressed in BP was calculated on the basis of the formula 83