Study on age determination by carbon in plant opal : Tests of carbon extraction and radiocarbon dating of plant opal

Autor: Nakamura, Toshio, Udatsu, Tetsuro, Tazaki, Hiroyuki, Toyama, Shuichi, Sugiyama, Shinji, Matsuda, Ryuji
Jazyk: japonština
Rok vydání: 2013
Předmět:
Zdroj: 名古屋大学加速器質量分析計業績報告書. 24:123-132
Popis: To measure 14C age directly on plant opal itself with accelerator mass spectrometry (AMS), we have extracted carbon contained in plant-opal samples separated from modern lining plants as well as ancient soil deposits at archeological sites, in particular, rice field remains. Carbon dioxide was separated and collected from plant-opal samples by using a radio-frequency furnace (HF-1O, Leco Corporation) which is used successfully to extract carbon in the metal iron. Carbon content of plant opal is not clearly known, and yields of CO2 from p1ant-opal samples were very low (<0.1%) in our experiment Nagoya University AMS 14C dating laboratory. We have conducted CO2 extraction for 15 samples, and we can get enough CO2 from only three samples to perform 14C dating even with AMS. The obtained 14C ages were a few thousand years older than expectations on the basis of archeological aspects. Even more, plant-opal samples extracted from modern living plants showed 14C ages as old as 3-6 ka BP. This implies that carbon in plant opal is not derived from carbon incorporated into the plants by photosynthesis. More studies are required to apply routinely 14C dating of plant-opal material.
名古屋大学年代測定総合研究センターシンポジウム報告
Databáze: OpenAIRE