A study on accurate age determination of volcanic eruptions by high-precision 140 dating and a wiggle matching analysison charred wood from volcanic deposits

火山沉积物焦木高精度140测年及摆动匹配分析准确测定火山喷发年龄的研究

基本信息

批准号：
13480020
负责人：
NAKAMURA Toshio
金额：
$ 9.15万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

项目摘要

Six wood samples were collected from Baitoushan Volcano in 2001 and two charred wood trunks were detected to have barks by careful inspection. The larger one of the two, with 102 annual rings, was used for ^<14>C dating. The annual rings were divided into 82 samples. The outer 20 annual rings were divided every two years because of narrow annual rings. From 21^<st> to 92^<nd> each annual ring was separated. Annual rings inner than 92^<nd> ring were broken and could not be separated. We have analyzed 35 samples out of 82 : approximately every three annual rings. The charcoal samples were processed by AAA treatments and converted to graphite in a routine method. The ^<14>C, ^<13>C and ^<12>C were measured with a HVEE Tandetron at Nagoya University. The obtained dates were compared with the INTCAL98 ^<14>C calibration data by wiggle matching. We obtained a probability distribution of one clear peak that corresponded to the time when the mixture of the outermost two rings was grown most probably in 935 cal AD, with errors of +8 and -5 years. This results implies that the eruption of Baitoushan Volcano had no relation with the fall of the Bo-hai State in AD926.ext, tephras from the Ulleung Island were studies chronologically. The U-Oki tephra is commonly accepted to have deposited in Japan at around 9.3-9.6 kaBP. The tephra layers U1, U2, U3 and U4 have been recognized on the Ulleung Island and their horizons were upper than the AT tephra (2.5 kaBP). During the survey at the Ulleung Island in 2002 and 2003, carbon samples for ^<14>C dating were collected from U2 (charred wood), U3 (organic soil) and U4 (charred twigs and organic soil). ^<14>C ages obtained for these layers were 5 kaBP for U2, 7.5-8.0 kaBP for U3 and 10-12 kaBP for U4. These results imply that the U-Oki tephra in Japan corresponds to U4. This is a really new finding, because the U-Oki tephra has been believed to correspond to U2.

2001年，从贝托汉火山（Baitoushan Volcano）收集了六个木材样品，并通过仔细检查发现了两个烧焦的木树干。 ^<14> c年代使用了两者中的较大一个，具有102个年度环。年度环分为82个样品。由于年度范围狭窄，每两年每两年将外部20个环。从21^<ST>到92^<nd>每个年度环分开。年内环超过92^<nd>环被打破，无法分离。我们已经分析了82个样本中的35个：大约每三个年度戒指。通过AAA处理处理木炭样品，并以常规方法转换为石墨。 ^<14> c， ^<13> c和 ^<12> c在纳戈亚大学用hvee tandetron测量。通过Wiggle匹配，将获得的日期与Intcal98 ^<14> C校准数据进行了比较。我们获得了一个透明峰的概率分布，这对应于最外面两个环的混合物最有可能在935 Cal AD中生长的时间，误差为+8和-5年。该结果意味着，贝托汉火山的喷发与AD926的Bo-hai州的倒塌没有关系。Ext，Ulleung Island的Tephras按时间顺序进行研究。 U-Oki Tephra通常被接受，将日本存放在9.3-9.6 kabp左右。 Tephra层U1，U2，U3和U4在Ulleung岛上已被认可，其视野比Tephra（2.5 kabp）的地平线高。在2002年和2003年在Ulleung岛进行的调查中，从U2（烧焦的木材），U3（有机土壤）和U4（烧焦的树枝和有机土壤）收集了 ^<14> C的碳样品。对于这些层获得的 ^<14> C年龄为U2的5 kabp，U3的U2和10-12 KABP为5 kabp。这些结果表明，日本的U-Oki Tephra对应于U4。这是一个非常新的发现，因为U-Oki Tephra被认为与U2相对应。

项目成果

期刊论文数量（66）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Toshio Nakamura, Hitoshi Fukumoto, Takumi Mitsutani, Etsuko Niu, Hirotaka Oda, Akiko Ikeda, Tomoko Ohta, Hisashi Fujine: "Comparison of radiocarbon ages with dendrochronology for Japanese trees."Summaries of researches using AMS at Nagoya University. XV.

Toshio Nakamura、Hitoshi Fukumoto、Takumi Mitsutani、Etsuko Niu、Hirotaka Oda、Akiko Ikeda、Tomoko Ohta、Hisashi Fujine：“日本树木的放射性碳年龄与树木年代学的比较。”名古屋大学使用 AMS 的研究摘要。