著者
田中 剛 Tanaka Tsuyoshi
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.26, pp.120-125, 2015-03

The scientific theory being supported by noble physical chemistry or famous researchers tends to be believed. The theory sometimes cites convenient descriptions to support their intended idea and skip over inconvenient observations. This report intend to lead the readers to the well-known "power spot at Mt. Kurama" resulted in high-energy γ-rays which causes electron-pair creation. No synthesized photo or figures is used in this report, but some inconvenient data are not mentioned to insist the intended idea. This report includes the some question what is the inconvenient hidden observation against this "power spot" theory. 明確な物理化学論理や著名な学説に裏付けられた論説は、信頼されがちである。ある企図された結論に誘うために、その論旨に都合の良い記述を引用し、対立する不都合な記述の引用をさける論説もある。この報告は、読者を「京随一の鞍馬山のパワースポットは、高エネルギーのγ線が頭脳中に電子対を生成する事による現象である」との結論に誘う事を試みた。この報告の中で、合成写真や虚偽の図版は、使われていない。しかし、結論に不都合ないくつかの情報にも触れられていない。不都合な事柄はなんだろうか?この報告文は、名古屋大学基礎セミナーAにおいて、それを探すための練習資料でもある。
著者
谷口 康浩
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.16, pp.34-53, 2005-03

第17回名古屋大学タンデトロン加速器質量分析計シンポジウム平成16(2004)年度報告 Proceedings of the 17th symposiumon Researches Using the Tandetron AMS System at Nagoya University in 2004\日時:平成17 (2005)年1月24日(月)、25日(火) 会場:名古屋大学シンポジオン Date:January 24th and 25th, 2005 Place:Nagoya University Symposion Hall
著者
三宅 芙沙 増田 公明 箱崎 真隆 中村 俊夫 門叶 冬樹 加藤 和浩 木村 勝彦 光谷 拓実 Miyake Fusa Masuda Kimiaki Hakozaki Masataka Nakamura Toshio Tokanai Fuyuki Kato Kazuhiro Kimura Katsuhiko Mitsutani Takumi
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.25, pp.137-143, 2014-03

Although some candidates for the cause of the mysterious cosmic ray event in AD 774-775 have been reported we were not able to specify. In order to investigate the occurrence rate of the 14C increase event like the AD 775 one, we measured 14C content in Japanese tree-rings during an extended periods. As a result,we detected the second 14C increase by significant amount from AD 993 to AD 994. From the occurrence rate (one 14C event/800 years),it was revealed that a large-scale SPE is the most plausible explanation for the 14C event. 775年の宇宙線イベントの原因について、いくつかの候補が挙がっていたが特定するのは難しい状況であった。本研究の年代を拡張した14C濃度測定により、993-994年にかけても似たような14C急増を発見した。また、994年イベントは日本産の2個体の樹木から存在を確認した。14Cイベントの発生頻度から、その原因として大規模SPEが妥当であると考えられる。見つかった14Cイベントの14C増加量は、観測史上最大のSPEの1O~数10倍に相当する。このような規模のSPEが仮に今日発生した場合、現代社会へ深刻な被害を及ぼすと想定される。今回の発見はこうした大SPEが将来において発生する可能性を示したものである。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
著者
長野 修二郎 Nagano Shujiro
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.26, pp.45-50, 2015-03 (Released:2015-05-18)

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
著者
鈴木 和博 中村 俊夫 南 雅代 池田 晃子 Suzuki Kazuhiro Nakamura Toshio Minami Masayo Ikeda Akiko
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.22, pp.121-134, 2011-03

Japanese Red foxes (Vulpes vulpes japonica) establish stable home ranges within particular areas or are itinerant with no fixed abode around human habitations. They are popular wild animals and feature prominently in the folklore of human culture. The population, however, was decreased until the beginning of the 1970's, and no fox has been seen since about 1975 in Kodenosawa, a small habitation about 17km NE from the urban area of Toyota City. A fox remains was found from the under floor of the Jizo-temple together with a ragged package of Nissin Chicken-Ramen which was used from 1971 to 1983. The fox's remains is c. 50 cm in body length. The left half of the remains exhibits soft tissues including skin and dried muscle, but the right half facing to the ground is completely decayed. To determine when the fox died, we measured 14C concentration in collagen extracted from a tooth and a rib of the remains. The δ13C (-18±1 ‰) normalized 14C concentrations are 129.2±0.4 pMC for the tooth and 129.0±0.4 pMC for the bone. Although the values intersect the calibration curve at 1962 and 1979, the 1979 age only agrees with the time span supported by the envelope of Chicken-Ramen. Drying of muscle tissue without rotting was likely to take place in cold winter. Thus, the fox's death is reasonably definable in the period from late November 1979 to early January 1980. The δ13C (-18±1‰) values suggest a diet containing a significant amounts of C4 food or protein with higher isotopic values. There is little C4 plants in Kodanosawa, but sizable amounts of cone were constantly brought from outside for cow's and chicken's food. A possible protein source is the herbivore and the omnivorous feeder within the area. An alternative may be marine fish and the derivatives including dog- and cat-food. To test whether the fox took food brought from outside or not, we analyzed the 87Sr/86Sr isotopic ratio of the remains. The 87Sr/86Sr isotopic ratios, 0.709439±0.000016 for the tooth and O.749464±0.000014 for the bone, are distinctly lower than those of wild boar's bone (0.709944±0.000016 and 0.709912±0.000012), river water (0.710079±0.000016) and the granite (0.710218±0.00016) that underlies the wide area of Toyota City. The initial 87Sr/86Sr ratio of 0.7096±0.0001 constrains the lowest isotopic ratio of water, plants and animals within the area. The distinctly lower 87Sr/86Sr values documents that the fox took sizable external food with higher δ13C values. After the disappearance of foxes from Kodenosawa around 1980, wild boars swelled in population. Voracious scavengers dug slope of hills side and paddy fields as they foraged for bulbs, yams, earthworms and grubs, and eventually ate voraciously paddy, sweet potatoes and beans in the field. This triggered the abandonment of cultivation of fields that face mountains. It is likely presumed that foxes were preventing wild boars from invading the human habitation through attacking Uribou, young wild boars. 愛知県豊田市小手沢町にある地蔵堂を建替えるために旧堂を取壊したとき,床下から乾潤びたキ ツネの遺骸が見つかった.遺骸の横に1971年から1983年まで使用されたデザインのチキンラーメ ンの袋があった. 口先から骨盤までの長さが約50cmの成獣である.遺骸の地面に接した右側半分 と尾は骨まで溶けて失われていた.左側半分には耳や皮膚も腐敗することなく保存されていたが, 体毛は全く残っていなかった.骨は白骨化し,前足の付け根の皮膚にのみ黒色の筋組織様のものが 付着していた. キツネの歯と骨から抽出したゼラチンコラーゲンの14C濃度(δ13C=-25‰に規格化)は129.2±0.4 pMCと129.0土0.4pMCである.この較正年代(1962年と1979 -1980) 年)とチキンラーメン袋の 使用期間および腐敗の無いことを総合して,キツネの死亡時期を1979年11月下旬~1989年1月上 旬と特定した.キツネのδ13Cは=-18±1‰である.小手沢地内にはC4植物が殆ど栽培されていない ので, 地域内の植物や小動物のみを食べていたと仮定すると,ほぼ完全な肉食をしない限りδ13C=-18‰にならない.一方,キツネの87Sr/86Sr比は0.70745 であり,分析誤差を超えて小手沢のイノシ シ(0.70993) ・川の水(0.71008) ・花崗閃緑岩の初生値(0.7096)より小さい. δ13C値と87Sr/86Sr比か ら,キツネは外来の餌(残飯を含む人間の食料やトウモロコシ主体の家畜飼料)を相当量摂取して いたと結論した. 地蔵堂の床下から見つかったキツネの死亡時期(1979年)は,小手沢地内でキツネが減少した時期 より約10年後で,イノシシの食害が顕在化する1980年代半ばに近い.人家に近い里山を縄張りと するキツネが,イノシシの人里進出を阻止していた可能性を考察した.第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
著者
鈴木 和博 中村 俊夫 南 雅代 池田 晃子 Suzuki Kazuhiro Nakamura Toshio Minami Masayo Ikeda Akiko
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.22, pp.121-134, 2011-03

Japanese Red foxes (Vulpes vulpes japonica) establish stable home ranges within particular areas or are itinerant with no fixed abode around human habitations. They are popular wild animals and feature prominently in the folklore of human culture. The population, however, was decreased until the beginning of the 1970's, and no fox has been seen since about 1975 in Kodenosawa, a small habitation about 17km NE from the urban area of Toyota City. A fox remains was found from the under floor of the Jizo-temple together with a ragged package of Nissin Chicken-Ramen which was used from 1971 to 1983. The fox's remains is c. 50 cm in body length. The left half of the remains exhibits soft tissues including skin and dried muscle, but the right half facing to the ground is completely decayed. To determine when the fox died, we measured 14C concentration in collagen extracted from a tooth and a rib of the remains. The δ13C (-18±1 ‰) normalized 14C concentrations are 129.2±0.4 pMC for the tooth and 129.0±0.4 pMC for the bone. Although the values intersect the calibration curve at 1962 and 1979, the 1979 age only agrees with the time span supported by the envelope of Chicken-Ramen. Drying of muscle tissue without rotting was likely to take place in cold winter. Thus, the fox's death is reasonably definable in the period from late November 1979 to early January 1980. The δ13C (-18±1‰) values suggest a diet containing a significant amounts of C4 food or protein with higher isotopic values. There is little C4 plants in Kodanosawa, but sizable amounts of cone were constantly brought from outside for cow's and chicken's food. A possible protein source is the herbivore and the omnivorous feeder within the area. An alternative may be marine fish and the derivatives including dog- and cat-food. To test whether the fox took food brought from outside or not, we analyzed the 87Sr/86Sr isotopic ratio of the remains. The 87Sr/86Sr isotopic ratios, 0.709439±0.000016 for the tooth and O.749464±0.000014 for the bone, are distinctly lower than those of wild boar's bone (0.709944±0.000016 and 0.709912±0.000012), river water (0.710079±0.000016) and the granite (0.710218±0.00016) that underlies the wide area of Toyota City. The initial 87Sr/86Sr ratio of 0.7096±0.0001 constrains the lowest isotopic ratio of water, plants and animals within the area. The distinctly lower 87Sr/86Sr values documents that the fox took sizable external food with higher δ13C values. After the disappearance of foxes from Kodenosawa around 1980, wild boars swelled in population. Voracious scavengers dug slope of hills side and paddy fields as they foraged for bulbs, yams, earthworms and grubs, and eventually ate voraciously paddy, sweet potatoes and beans in the field. This triggered the abandonment of cultivation of fields that face mountains. It is likely presumed that foxes were preventing wild boars from invading the human habitation through attacking Uribou, young wild boars. 愛知県豊田市小手沢町にある地蔵堂を建替えるために旧堂を取壊したとき,床下から乾潤びたキ ツネの遺骸が見つかった.遺骸の横に1971年から1983年まで使用されたデザインのチキンラーメ ンの袋があった. 口先から骨盤までの長さが約50cmの成獣である.遺骸の地面に接した右側半分 と尾は骨まで溶けて失われていた.左側半分には耳や皮膚も腐敗することなく保存されていたが, 体毛は全く残っていなかった.骨は白骨化し,前足の付け根の皮膚にのみ黒色の筋組織様のものが 付着していた. キツネの歯と骨から抽出したゼラチンコラーゲンの14C濃度(δ13C=-25‰に規格化)は129.2±0.4 pMCと129.0土0.4pMCである.この較正年代(1962年と1979 -1980) 年)とチキンラーメン袋の 使用期間および腐敗の無いことを総合して,キツネの死亡時期を1979年11月下旬~1989年1月上 旬と特定した.キツネのδ13Cは=-18±1‰である.小手沢地内にはC4植物が殆ど栽培されていない ので, 地域内の植物や小動物のみを食べていたと仮定すると,ほぼ完全な肉食をしない限りδ13C=-18‰にならない.一方,キツネの87Sr/86Sr比は0.70745 であり,分析誤差を超えて小手沢のイノシ シ(0.70993) ・川の水(0.71008) ・花崗閃緑岩の初生値(0.7096)より小さい. δ13C値と87Sr/86Sr比か ら,キツネは外来の餌(残飯を含む人間の食料やトウモロコシ主体の家畜飼料)を相当量摂取して いたと結論した. 地蔵堂の床下から見つかったキツネの死亡時期(1979年)は,小手沢地内でキツネが減少した時期 より約10年後で,イノシシの食害が顕在化する1980年代半ばに近い.人家に近い里山を縄張りと するキツネが,イノシシの人里進出を阻止していた可能性を考察した.
著者
三宅 芙沙 増田 公明 箱崎 真隆 中村 俊夫 門叶 冬樹 加藤 和浩 木村 勝彦 光谷 拓実 Miyake Fusa Masuda Kimiaki Hakozaki Masataka Nakamura Toshio Tokanai Fuyuki Kato Kazuhiro Kimura Katsuhiko Mitsutani Takumi
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.25, pp.137-143, 2014-03

Although some candidates for the cause of the mysterious cosmic ray event in AD 774-775 have been reported we were not able to specify. In order to investigate the occurrence rate of the 14C increase event like the AD 775 one, we measured 14C content in Japanese tree-rings during an extended periods. As a result,we detected the second 14C increase by significant amount from AD 993 to AD 994. From the occurrence rate (one 14C event/800 years),it was revealed that a large-scale SPE is the most plausible explanation for the 14C event. 775年の宇宙線イベントの原因について、いくつかの候補が挙がっていたが特定するのは難しい状況であった。本研究の年代を拡張した14C濃度測定により、993-994年にかけても似たような14C急増を発見した。また、994年イベントは日本産の2個体の樹木から存在を確認した。14Cイベントの発生頻度から、その原因として大規模SPEが妥当であると考えられる。見つかった14Cイベントの14C増加量は、観測史上最大のSPEの1O~数10倍に相当する。このような規模のSPEが仮に今日発生した場合、現代社会へ深刻な被害を及ぼすと想定される。今回の発見はこうした大SPEが将来において発生する可能性を示したものである。
著者
田中 剛 Tanaka Tsuyoshi
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.26, pp.120-125, 2015-03

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
著者
中村 俊夫 NAKAMURA Toshio
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.22, pp.23-36, 2011-03 (Released:2011-03-00)

第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
著者
中村 俊夫
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.15, pp.103-112, 2004-03

第16回名古屋大学タンデトロン加速器質量分析計シンポジウム(平成15年(2003年度)報告 Proceedings of the 16th Symposium on Researches Using the Tandetron AMS System at Nagoya University in 2003 日時:平成16(2004)年1月22日(木)、23日(金) 会場:名古屋大学シンポジオン Date:January 22nd and 23rd,2004 Place:Nagoya University Symposion Hall
著者
中村 俊夫 NAKAMURA Toshio
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.15, pp.103-112, 2004-03

Accurate knowledge on marine reservoir effect is particularly important to estimate active periods of archeological sites in Japan. Since most of archeological sites are situated in an alluvial plain in Japan, archeological remains include inevitably marine products. To obtain precise calendar ages for marine samples such as shell fragments and sea mammal bones by ^<14>C dating, a correction for marine reservoir effect is necessary. In addition, ^<14>C ages on a collagen fraction extracted from human bones should be corrected for the sources of their diet, the uptake ratio of terrestrial food to marine one. However, the local fluctuation of marine reservoir effect around Japan Islands is not known well. This study gives a brief summary of a calibration method for ^<14>C ages of samples containing marine-derived carbon.
著者
坂本 稔 小林 謙一 尾嵜 大真 中村 俊夫
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.16, pp.91-94, 2005-03

第17回名古屋大学タンデトロン加速器質量分析計シンポジウム平成16(2004)年度報告 Proceedings of the 17th symposiumon Researches Using the Tandetron AMS System at Nagoya University in 2004\日時:平成17 (2005)年1月24日(月)、25日(火) 会場:名古屋大学シンポジオン Date:January 24th and 25th, 2005 Place:Nagoya University Symposion Hall
著者
中川原 育子 谷口 陽子 佐藤 一郎 中村 俊夫 NAKAGAWARA Ikuko TANIGUCHI Yoko SATO Ichiro NAKAMURA Toshio
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.23, pp.127-137, 2012-03

The Kizil Grottoes, the largest Buddhist monastery complex in the Xinjian region of China, is decorated with wall paintings - the chronological dates of which are still under debate. This study aims to give some clarification regarding the chronological dates using AMS-14C dating of chaff tempers taken from the earthen renders of the wall paintings. l4C studies previously carried out by Chinese and German researchers had resulted in divergent dates often extending back hundreds of years earlier than hypothesized within the chronology of art history, which has created confusion. Six samples from six wall painting fragments (Caves 8 [III8425], 38 [III8700], 171 [III8793, III8891], 207[III9148b(d)], and 224[III8865(a)]) held in collections at the Museum für Asiatische Kunst in Berlin were taken and analysed with 14C-AMS at the Center of Chronological Research at Nagoya University in Japan. As reference, nine dating results analysed between 1995 and 1998 at Nagoya University were also shown in the list. Dates were obtained for only three out of the six samples: cal AD 128-216 [Cave 8], cal AD 255-306 and cal AD 312-34 [Cave 171], and 90-70 cal BC [Cave 224]; most of these extended back earlier than reference 14C data from the Chinese and German studies and far earlier than dates suggested by the timeline of art history. Even the Chinese and German reference dates derived in the past from 14C analysis often show varied dates occurring earlier than those represented in art history. This may indicate that old chaff was used in renders for the Kizil wall paintings probably as a form of re-use of old mud bricks, or that the chronology of art history must be drastically reconsidered, both of which would require further AMS-14C dating studies with careful and comprehensive sampling from well-documented contexts.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
著者
渡邊 隆広 奈良岡 浩 西村 弥亜 中村 俊夫 仙田 量子 河合 崇欣
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
no.15, pp.199-205, 2004-03

バイカル湖湖底堆積物試料中の高分子直鎖状炭化水素、及びバクテリア由来有機分子であるホパノイド化合物の分子レベル安定炭素同位体比分析を行い、過去における湖内バクテリア活動の復元と環境変化の考察を行った。最終氷期から完新世への移行期において、メタン酸化バクテリアの寄与が増大していたことが明らかになった。この結果は、過去における気候変動に対応して湖水循環が停止、もしくは極めて弱くなっていたことを示唆する。\\Several organic geochemical studies on sedimentary photosynthetic pigments, lignin phenols and lipids from vascular plants have been conducted using Lake Baikal sediment core [Orem et al., 1997; Tani et al., 2002]. However, these investigations have not elucidated past limnological conditions such as redox changes in Lake Baikal. The sulfur isotope compositions of pyrite indicated a variation of SRB activity in response to glacial/interglacial climate changes [Watanabe et al., 2004]. In this study prokaryote biomarkers including hopanoid and acyclic isoprenoid compound will be examined for the sedimentary profiles of bacterial activities including methanotrophic bacteria. Organic compounds of higher plant origin, such as high molecular n-alkanes, n-ketones and n-alkanols are relatively abundant in the Ver98-1 St.5 sediment core (up to 5.6, 1.8, and 11.7 μg/g dry sed., respectively). The abundance of partly autochthonous organic matter, such as phytol and low molecular alkanols is relatively low. It has revealed significant difference in the molecular composition between the warm periods and the cool periods, which is consistent with the organic carbon and total nitrogen concentration and TOC/TN ratios. The increase in terrigenous organic molecules in the warm periods can be explained by the increased inflow of river water. In the deepest part of modern Lake Baikal, ca. 9 mg/l dissolved oxygen occurs, which suggests a large-scale vertical convection in the lake in spite of its great depth (1634m). Watanabe et al. [2003] suggested less-oxic conditions of Lake Baikal bottom water in climate transition periods, such as Younger Dryas (YD), based on high TS contents (up to 13mg/g dry sed) and high TS/TOC ratios (up to 0.5 atomic ratio), being much larger than average TS/TOC ratios of freshwater and normal oxic marine sediment. The high TS/TOC are usually observed not only as a result of less-oxic condition but also diagenetic pyritization. We have measured δ^<13>C of bacterial biomakers and δ^<34>S of pyrite through the YD event (ca.12kyr B.P.). Hop-17(21)-ene is the most abundant among unsaturated hopanoids throughout the Holocene and YD sediment (32-68 ng/g dry sediment). Furthermore, high amounts of saturated hopanoids are present with 17δ(H), 21δ(H)-homohopane and 17δ(H), 21δ(H)-hopane dominating (up to 1045 and 381 ng/g dry sediment, respectively) in the Holocene. 17δ(H), 21δ(H)-homohopane and 17δ(H), 21δ(H)-hopane vary isotopically in a narrow range from -30.8 to -34.7‰, which suggests that the δδ hopanes could be derived from chemotrophic bacteria. Hop-17(21)-ene in the YD becomes more depleted in ^<13>C (〜-43‰) than that in the Holocene by 〜10‰, implying an increase of methanotrophic bacterial activity. In addition, squalane is depleted in ^<13>C (-46.2‰) compared to the total organic carbon by 20‰. Such ^<13>C-depleted squalane suggests that archea have directly or indirectly introduced ^<13>C-depleted methane-derived carbon into the biomass. The methane-involving anaerobic bacterial activity suggests the decrease of dissolved oxygen content in deeper part of Lake Baikal at the YD rapid cooling event. These isotopic signatures suggest that less oxic conditions associated with a water circulation change occurred rapidly within a time interval of less than 1000 yr in response to a global climatic change at the late Quaternary. Since lake water circulation exerts a great influence especially on the geochemical cycle and biological activity in Lake Baikal, reconstruction of paleo-redox conditions and water circulation changes in the lake are indispensable to identify detailed changes in biological activity and lake ecosystems with respect to climate changes.タンデトロン加速器質量分析計業績報告 Summaries of Researches Using AMS 2003 (平成15)年度
著者
中村 俊夫 宇田津 徹朗 田崎 博之 外山 秀一 杉山 真二 松田 隆二 Nakamura Toshio Udatsu Tetsuro Tazaki Hiroyuki Toyama Shuichi Sugiyama Shinji Matsuda Ryuji
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.24, pp.123-132, 2013-03

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
著者
鈴木 和博 Suzuki Kazuhiro 中村 俊夫 Nakamura Toshio 加藤 丈典 Kato Takenori Takenori 池田 晃子 Ikeda Akiko 後藤 晶子 Goto Akiko 小田 寛貴 Oda Hirotaka 南 雅代 Minami Masayo 上久保 寛 Kamikubo Hiroshi 梶塚 泉 Kajizuka Izumi 足立 香織 Adachi Kaori 壺井 基裕 Tsuboi Motohiro 常磐 哲也 Tokiwa Tetsuya 太田 友子 Oota Tomoko 西田 真砂美 Nishida Masami 江坂 直子 Esaka Naoko 田中 敦子 Tanaka Atsuko 森 忍 Mori Shinobu ダンクリー ダニエル Dunkley Daniel J. クシャク モニカ Kusiak Monika A. 鈴木 里子 Suzuki Satoko 丹生 越子 Niu Etsuko 中崎 峰子 Nakazaki Mineko 仙田 量子 Senda Ryoko 金川 和世 Kanagawa Kazuyo 熊沢 裕代 Kumazawa Hiroyo
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.19, pp.26-38, 2008-03

Umi is located along the Kamimura River within the Kamiyahagi area of southeastern Ena City, Gifu Prefecture. The name 'Umi' means sea or large lake; however, there are no lakes in the mountainous Kamiyahagi area. The Tokai Gou (torrential rain) flood of September 11-12, 2000 destroyed embankments along the river, and exposed sedimentary layers that are typical of a lacustrine depositional setting. This confirms the existence of a paleo-lake from which the name Umi originated. The ^<14>C ages, ranging from 280±37 to 345±25 BP, appear to be contemporaneous with Tensho Earthquake that occurred in central Japan on January 18, 1586.
著者
小田 寛貴 Oda Hirotaka 本庄 かや子 Honjo Kayako 森 靖裕 Mori Yasuhiro 安西 雅希 Anzai Masaki
出版者
名古屋大学年代測定資料研究センター
雑誌
名古屋大学加速器質量分析計業績報告書
巻号頁・発行日
vol.16, pp.181-190, 2005-03

This paper reports radiocarbon dating of the charred-carbonaceous samples remained on a Satsumon pottery excavated from the Yafurai-3 site, Kamiiso-cho, Hokkaido, Japan. The Satsumon pottery is a small pot with three grooved lines. The typological analysis indicates that the pottery was made in the early Satsumon period. Although the charred-carbonaceous samples have older radiocarbon ages than the typological age, the δ^<13>C value of the sample suggested that the carbonaceous materials originated from the marine products. The radiocarbon ages, therefore, were corrected for the marine reservoir effect in Hokkaido, and calibrated to the calendar age. The calibrated ages showed that the Satumon pottery was used before the 9th century.