Radiocarbon dating of a very large grandidier baobab, the giant of Bevoay

Adrian Patrut, Roxana T. Patrut, Jean-Michel Leong Pock-Tsy, Stephan Woodborne, Laszlo Rakosy, Ileana-Andreea Ratiu, Jenő Bodis, Pascal Danthu
2020 Studia Universitatis Babe?-Bolyai Chemia  
The article presents the AMS (accelerator mass spectrometry) radiocarbon dating results of the Giant of Bevoay, which is a very large Grandidier baobab (Adansonia grandidieri Baill.) of Madagascar. The investigation of this baobab shows that it has a cluster structure, which consists of 3 perfectly fused stems. The calculated wood volume of the tree is 520 m 3 , which makes it the third largest Grandidier baobab and also the third largest individual of all Adansonia species. Two samples were
more » ... Two samples were collected from the outer part of the stems. The oldest dated sample segment had a radiocarbon date of 525 ± 23 BP, which corresponds to a calibrated age of 585 ± 10 years. According to this value, the Giant of Bevoay is 825 ± 50 years old. 157 EXPERIMENTAL SECTION Sample collection. The investigated wood sample was collected with a Haglöf CH 800 increment borer (0.80 m long, 0.0108 m inner diametre). A number of four tiny pieces/segments, of the length of 10 -3 m, were extracted from predetermined positions along the sample. The segments were processed and investigated by AMS radiocarbon dating. Sample preparation. The α-cellulose pretreatment method was used for removing soluble and mobile organic components [24] . The resulting samples were combusted to CO 2, which was next reduced to graphite on iron catalyst [25, 26] . The resulting graphite samples were analysed by AMS. AMS measurements. The radiocarbon measurements were done at the AMS Facility of the iThemba LABS, Johannesburg, Gauteng, South Africa, using the 6 MV Tandem AMS system [27] . In all cases, the obtained fraction modern values were finally converted to a radiocarbon date. The radiocarbon dates and errors were rounded to the nearest year. Calibration. Radiocarbon dates were calibrated and converted into calendar ages with the OxCal v4.4 for Windows [28] , by using the SHCal20 atmospheric data set [29] .
doi:10.24193/subbchem.2020.4.12 fatcat:h54z2urajjfivpr7aakcqkeiym