浙江余姚田螺山遗址土壤植硅体AMS^(14)C测年初步研究  

A PRIMARY STUDY ON AMS ^(14)C DATING OF PHYTOLITH AT TIANLUOSHAN SITE,ZHEJIANG PROVINCE

作　　者：金和天[1] 潘岩[1] 杨颖亮[1] 秦岭[1] 孙国平[2] 郑云飞[2] 吴小红[1] 

机构地区：[1]北京大学考古文博学院,北京100871 [2]浙江省文物考古研究所,杭州310014

出　　处：《第四纪研究》2014年第1期1-7,共7页Quaternary Sciences

基　　金：科技部国家科技支撑计划项目中华文明探源工程(三)(批准号:2010BAK67B01);国家文物局全国文物保护科学和技术研究项目重点科研基地课题"小样品碳十四年代测定方法研究"(批准号:20110212)共同资助

摘　　要：植硅体(phytolith)是植物体细胞中非晶体二氧化硅脱水后的产物。非晶体二氧化硅的一个聚合基有活性,能够结合植物细胞中的有机碳。植物体死亡后,非晶体二氧化硅脱水,形成坚硬的硅质物,具有抗风化、抗腐蚀、耐酸的特点。植物原生的有机碳被封闭在植硅体内,与外界隔绝,被很好地保存了下来。利用植硅体进行^(14)C年代测定,可以得到植物体死亡的年龄。本研究采集浙江田螺山新石器时代遗址水稻田土壤样本,提取其中的植硅体,通过元素分析、红外光谱进行鉴定,并利用加速器质谱对植硅体样品进行^(14)C年代测定,以期得到水稻田的使用年代;对同层位炭化植物种子也利用加速器质谱进行了^(14)C年代测定。对比结果显示,植硅体年代数据与炭化植物种子的年代在3σ误差范围内一致,植硅体年代数据的中值比炭化植物种子的年代数据中值略有偏老。可以认为植硅体的年代基本上代表了水稻田被使用的年代,植硅体测年可以作为植物年代测定的有效手段。同时,本文尝试针对本研究植硅体年代数据偏老的部分原因做了一点讨论。Phytolith is the product of dehydration reaction from amorphous silicon dioxide in plant. Amorphous silicon dioxide has an active hydroxyl group which can combine the organic carbon in the plant. After plant decays, the amorphous silicon dioxide is dehydrated and becomes rigid siliceous material which is resistant to weathering and corrosion and safe in acid condition. The organic carbon from the plant is trapped in phytolith and isolated from the carbon exchanging between the carbon reservoirs during burial. These characteristics of phytolith make it possible to be dated by 14C-AMS. The method of dating phytolith by 14C-AMS is very important to be applied in the archaeological and environmental researches in South China where charred seeds and animal bones are difficult to be preserved because of the acid soil conditions and where the phytolith is well-preserved. Phytolith becomes an important unique sample to solve the dating problems where the plant and animal remains are lacking at many early neolith sites in South China. Tianluoshan site is belong to Hemudu culture which is famous as early rice agriculture. The site is located in Sanqishi Town,Yuyao City,Zhejiang Province and it is in the basin which is to the north of Yaojiang River valley, and the site is 7 kilometers far from Hemudu site. The plant and animal remains are well preserved because of the water logged condition at this site. The soil samples,rich in phytolith,were collected from the cultural layer,layer 7 of T703 which is identified as rice paddy field at the site phytolith serve as good dating samples in our research. The well preserved plant remains and soil samples rich in 20g soil was used as one sample. First,hydrogen peroxide was used to clean up the organic residues in soil sample. Then the phytolith was extracted by sedimentation and floatation repeatedly. After drying in the muffle furnace,extracted sample was weighted. The net weight is 1.06g. Extracted sample was analyzed by Elements Analyzer and Infrared Spectroscopy Analyzer. A

关 键 词：植硅体 加速器质谱(AMS) 碳十四年代测定(^14C) 新石器 田螺山遗址 

分 类 号：K871.13[历史地理—考古学及博物馆学] Q914.9[历史地理—历史学]