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We, the members of the Division for Chronological Research at the Institute for Space-Earth Environmental Research at Nagoya University, held a regional contribution program for the higher grade elementary school students on August 7-8, 2018: “Let’s study geology in Tono region”. The thirty-six students took part in the program to experience earth sciences. The first day they travelled to Mizunami, Gifu by bus and visited the Hesoyama geological site to observe Miocene fossils and sediments in Mizunami group, Science World (Gifu tip technology experience center) to experience scientific experiments and science show, Mizunami Fossil Museum to observe exhibitions of fossils, and Mizunami Earth Corridor to experience the evolution of the Earth. After then, they went to the Matsugase field education site along Toki river to collect fossils such as mollusks, crabs, fishes, mammals, and plants. We successfully made a meaningful field program. The second day began with two lectures on geology and rocks in Tono region by Professor Enami and on Mizunami fossils by Lecturer Hayashi. After the lectures, the students took part in a hands-on experiment of making fossil replica. In the afternoon, they discussed about what was learned during this experiential learning program and summarized it in posters. Finally, they made poster presentation by groups. The program ended a success. The post-program questionnaire shows that the participants enjoyed the program a lot and learned many new things., 宇宙地球環境研究所は，環境学研究科地球環境科学専攻地質・生物学講座の林誠司講師の協力のもと，平成30年8月7日（木）と8日（金）の2日間にわたり，小学高学年生36名を対象とした夏休み体験学習「東濃地方の地層について学ぼう」を行った．初日は，大型バスをチャーターして岐阜県瑞浪市に出向き，瑞浪の地層観察，岐阜県先端技術体験センターサイエンスワールド，瑞浪市化石博物館，地球回廊の見学，そして最後に土岐川の松ヶ瀬河原で化石採集を行った．2日目は，名古屋大学研究所共同館Ⅱにおいて，野外実習での経験や学んだ知識を深めるため，講義，室内実習，子どもたちによる発表会を行った．子ども達が教室での講義だけでは得られ難い実体験の機会は，子どもたちの科学への興味や関心をより高めるきっかけになり，本体験学習の目的は十分達成できたと考えられる．

We, the members of the Division for Chronological Research at the Institute for Space-Earth Environmental Research at Nagoya University, held a regional contribution program for the higher grade elementary school students on August 3–4, 2017: “Investigation of natural and environmental history in the Tokai region”. Twenty-seven students observed natural samples to experience earth and archaeological sciences. The first day began with lectures on tephra chronology and dendrochronology. After the lecture, the students took part in several hands-on experiments by using tephra and annual tree rings. On the second day they travelled to Shizuoka by bus and visited the Museum of Natural and Environmental History, Shizuoka to study natural and environmental history in the Tokai region. Later in the day they went to Miho no Matsubara to observe the states of coastal erosion and pine wilt disease. Finally, they went to Nihondaira to study about a movement of the earth’s crust. The program ended a success. The post-program questionnaire shows that the participants enjoyed the program and learned many new things., 宇宙地球環境研究所年代測定研究部は，静岡県ふじのくに地球環境史ミュージアムの山田和芳教授，菅原大助准教授，静岡大学理学部の北村晃寿教授と協力し，平成29年8月3日（木）と4日（金）の2日間にわたり，小学高学年生27名を対象とした夏休み体験学習「東海の地球環境史を学ぼう」を行いました．教室での講義だけでは得られ難い実体験の機会は，子どもたちの科学への興味や関心をより高めるきっかけになり，本体験学習の目的は十分達成できたと考えられる．

Electron probe microanalysis (EPMA) is being performed with two electron microprobes (JCXA–733, JEOL, Tokyo) for various applications, including the CHIME dating and quantification of ultra-trace elements at the Division for Chronological Research, Institute for Space-Earth Environmental Research, Nagoya University. One of the electron microprobes is mainly used for the CHIME dating of rock-forming minerals. The other is used for various applications., 名古屋大学宇宙地球環境研究所年代測定研究部では、2台の電子プローブマイクロアナライザー(EPMA）を用いてCHIME年代測定やさまざまな分析を行っている。2016年度はEPMAなどの装置を古川記念館から研究所共同館IIに移設した。これまで2台のEPMAは異なるソフトウェアで制御していたが、装置の改造を行い共通のハードウェア・ソフトウェアで分析することができるようにした．

An AMS system (Model 4130-AMS) dedicated to 14C measurements, built by High Voltage Engineering Europe (HVEE), B.V., The Netherlands, was delivered to Nagoya University in 1996/97. Acceptance tests of its performance on carbon isotope measurements were completed in January of 1999, and routine measurements began in mid-2000. Since completion of the acceptance tests in early 1999, we have encountered a lot of troubles with the machine, particularly in 2002. Since the end of 2002, the machine has worked relatively well, expect for minor problems. The standard deviation (one sigma) of the 14C/12C ratio is around ±0.3% to ±0.4% (a bit larger than the uncertainty of about ±0.3% calculated from 14C counting statistics) and that of the corresponding 13C/12C ratio is ±0.03% to ±0.07%, as are tested for HOxII targets. The number of targets measured was 330, 1430, 2077, 1003, 1,979, 1679, 1772, 1115, 1339, 866, 1300, 1701, 1449, 1634, 1351, 1741, 1156 in each year from 1999 to 2015, respectively, and total number of targets measured by the end of 2015 is 23,921. We briefly describe the maintenance processes and application results of the AMS system in 2015. The Tandetron AMS system at Nagoya University worked rather well in 2015, with only minor failures, such as (1) X-Y direction movement trouble of target surface to change sputtering positions, (2) compressed-air-leakage problem of an air cylinder to exchange targets to be measured, (3) unexpected break down of high voltage of accelerator without any sparks, without any specific reasons, (4) ion source cleaning due to shortage of Cs in the container, (5) high temperature problem of the circulating water for cooling down the power supply system for two high-energy mass-analyzing magnets. The error no. (3) above became a serious problem at last in December, because we cannot reset a system diagnostic alarm concerning a high voltage spark at last. It was finally found out that the problem caused by a malfunction of the spark-detector circuit unit, mounted on the top of the accelerator tank. \In 2015, we also carried out many application programs of 14C measurements. The reports are included in this Proceedings volume., 名古屋大学宇宙地球環境研究所年代測定研究部シンポジウム報告

Electron probe microanalysis (EPMA) is performed using two electron micro probes (JCXA- 733, JEOL, Tokyo) CHIME dating, quantitative EPMA of ultra-trace element and other applications at the Division for Chronological Research, Institute for Space-Earth Environmental Research, Nagoya University. The one is mainly used for CHIME dating of rock-forming minerals. The other is used for a variety of applications, such as quantitative EPMA of ultra-trace elements and CHIME dating., 名古屋大学宇宙地球環境研究所年代測定研究部には、2台の電子プローブマイクロアナライザー(EPMA）を用いて、CHIME年代測定及びさまざまな分析を実施し、教育・研究を行っている。2015年度は、極微量元素の定量分析の確度向上のため、高計数率エックス線の高確度測定法の開発やさまざまな地質帯の CHIME年代測定などを行った。また、EPMAの保守性維持や省電力化に向けた試みを行っている。, 名古屋大学宇宙地球環境研究所年代測定研究部シンポジウム報告

The long-term and high time resolution analysis of inorganic elements from Lake Baikal sediment revealed that source provenance of Rb has been changed during last glacial and post glacial period. Simultaneous fluctuations between the Rb/Sr ratio and the mean grain size indicate that the Rb/Sr ratio was influenced from the precipitation change (humidity) during the post glacial period. On the other hand, it can be supposed that the influence of loess sediment on the Rb/Sr ratio was found during the last glacial period. The 200-yr period variation of the Rb/Sr raito was found during the post glacial period. This 200-yr period is very close to those of TSI variation. This result indicates the strong influence of solar irradiance on the precipitation change in Lake Baikal region., 南シベリア南東部に位置するバイカル湖より長さ436cmの堆積物試料を採取し、堆積物中の無機金属元素測定を行った。試料は1cm間隔で切り分けられ、試料間隔ごとの時間解像度は約70年と見積もられる。堆積物中のRb及びSrは、完新世(約11,700年前から現在)にかけて、それぞれKとCaに対して高い相関を示 した。一方、後期更新世(約33,000年前から11,700 年まで)においては、SrとCaは高い相関を示すが、RbとKに相関は見られなかった。乾燥化した時代において、Rbの濃集が起きていたと考えられる。Rb/Sr比の分布は、後期更新世において冬季モンスーン(East Asian winter monsoon)の指標である中国レス堆積物の粒度分布(Sun et al., 2011)とよく対応を示した。寒冷、乾燥期においてバイカル湖堆積物中のRb/Sr比が冬季モンスーンの指標となりうる可能性を示唆している。, 名古屋大学宇宙地球環境研究所年代測定研究部シンポジウム報告

To reconstruct climatic and environmental changes in the south Tibetan Plateau, a 3.77-m-long sediment core (PY608E-PC) was obtained from Lake Pumoyum Co in August 2006. Because terrestrial plant residues are extremely rare in this core, radiocarbon dating was performed on the total organic carbon fraction. We also estimated the old carbon effect and radiocarbon reservoir age of the total organic carbon fraction. Using these estimates, a new radiocarbon chronology for past climatic changes from ca. 12,500 to 700 cal BP was established. The linear sedimentation rate of the core was founded to be constant at 32.0 cm/kyr, indicating stable sedimentation conditions in Lake Pumoyum Co from the period of the Younger Dryas to the Holocene., 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

大陸内部における環境変動を詳細に解析するために、フブスグル湖堆積物(X106)を用いて、元素分析(全有機態炭素;TOC、全窒素;TN、全硫黄;TS)及びこれらの元素安定同位体分析 (δ^C_,δ^N_,δ^S_) の測定を行った。本試料は、名古屋大学年代測定センターにて、加速器質量分析計(AMS)を用いて放射性炭素年代測定が行われ、堆積年代は約 23,000kyrBPである。X106堆積物試料におけるTOC、TN、δ^C_、及び δ^N_の変動から、フブスグル湖における炭素、窒素の循環は、地球規模の変動よりも、むしろ湖内生物活動に起因することが示唆された。また、最終氷期から間氷期への気候遷移期(18〜10kyrBP)において、TS、 δ^S_の急激な増加が認められ、この時期における、硫酸イオンの急激な湖水への流入が示唆された。, 第19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18(2006)年度報告 Proceedings of the 19th symposiumon on Chronological Studies at the Nagoya University Center for Chronological Research in 2006 日時:平成19 (2007)年1月15日(月)～17日(水) 会場:名古屋大学シンポジオン Date:January15th-17th, 2007 Venue:Nagoya Uhiversity Symposion Hall