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CHIME (chemical Th-U-total Pb isochron method) dating, quantitative electron probe microanalysis (EPMA) of ultra-trace elements and ultra-light elements are performed using two JCXA-733 (JEOL, Tokyo) at Division for Chronological Research, Institute for Space-Earth Environmental Research (ISEE), Nagoya University. The 733-LSS type specimen stage has been installed and both instruments supports large size specimen holders. Available analyzing crystals are: LDE1, LDE2, NSTE, TAP, PET, and LiF. The software for quantitative analysis supports Bence-Albee method, PAP and PROZA96 models.

The formation age of beachrock has been determined based on the 14C age of biological origin carbonate (i.e. shell and coral) collected from beachrock. However, it indicates the death age of the organism and does not indicate an accurate age of the beachrock formation. Therefore, it is necessary and indispensable to measure directly the age of the cement material of the consolidated intertidal sediments. We sampled cement materials attached on the surface of cobbles or boulders of the conglomeratic beachrocks formed on the coasts of Sasebo, Nagasaki Prefecture, Shimauratou Island, Miyazaki Prefecture, Zamami Island, Aka Island, Tokashiki Island, Geruma Island, Iheiya Island, Bise and Tsuha coast of Okinawa Prefecture. The cement materials were scraped using a small electric hand drill with a stainless steel drill edge of 2−3 mm in diameter and a stainless steel brush of 1 cm in diameter. A sample of 20 mg powder was used for AMS14C dating and analysis of chemical composition by ICP-MS. Except for the Sasebo samples, the cement materials were rich in calcium carbonate; 69.1% for Hiinohama and 85.4% and 74.2% for Zamami samples. However, the carbonate content of the Sasebo sample was as low as 0.6%, and high in Al (6.95%) and Fe (4.91%). The δ13C values of the whole samples except for the Sasebo sample were in a range between −4‰ and +4‰, suggesting that the carbon of the cemented material originated from seawater. The 14C ages of three in situ shell samples (Claudiconcha japonica) lying under the boulders of conglomeratic beachrock of Sasebo were Modern (101.6−102.5 pMC). The formation ages of conglomeratic beachrock collected at Hiinohama of Shimaura Island indicated during 3270−3220 BP and during 2920−2510 BP, respectively. The 14C ages of the two cemented materials collected from Zamami Island were 1043±26 BP and 1020 ±26 BP. Other cemented materials of the beachrock from Aka Island yielded ages of 1531±26 BP and 1336 ±26 BP, being younger than those of shell and coral samples from the same beachrocks. Results of this study demonstrate that the pretreatment method in this study was valid to determine the formation age of the conglomeratic beachrock.

CHIME (chemical Th-U-total Pb isochron method) dating, quantitative electron probe microanalysis (EPMA) of ultra-trace elements and ultra-light elements are performed using two JCXA-733 (JEOL, Tokyo) at Division for Chronological Research, Institute for Space-Earth Environmental Research (ISEE), Nagoya University. X-ray fluorescence spectrometer (XRF-1800, Shimazu, Kyoto) and X-ray diffractometer (MiniFlex, Rigaku, Tokyo) are also provided for the joint research program of ISEE in addition to JCXA-733. Phase analysis software, MATCH! 3 (Crystal Impact GbR) has been introduced for XRD data analysis.

CHIME (chemical Th-U-total Pb isochron method) dating and quantitative analysis of ultra-trace elements are performed with two JCXA-733 (JEOL, Tokyo) electron probe microanalyzers (EPMA) at Division for Chronological Research, Institute for Space–Earth Environmental Research (ISEE), Nagoya University. X-ray fluorescence spectrometer (XRF-1800, Shimadzu, Kyoto) and X-ray diffractometer (MiniFlex, Rigaku, Tokyo) are also provided for the joint research program of ISEE in addition to EPMA. The control computers of XRF and XRD have been replaced by the 64-bit version of Windows 10 based computers., 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、日本電子株式会社製JCXA-733）を用い、U-Th-Pb系のサブグレン年代測定や極微量元素定量分析を実施している。また、今年度から蛍光エックス線装置（株式会社島津製作所製XRF-1800）およびエックス線回折計（株式会社リガク製MiniFlex）も共同利用・共同研究対処機器としている。XRFとXRDの制御用PCを64ビット版Windows 10を搭載したものに置き換えた。

The Institute for Space-Earth Environmental Research, Nagoya University, held a regional contribution program of “Letʼs study earthquake and active fault around Nagoya city” for the higher grade elementary school students on July 31–August 1, 2019. The twenty-five students took part in the program. The first day they went to Ogaki and Motosu, Gifu by bus and visited the Kinsho-zan Kaseki-kan (Museum) to observe the Permian fossils, Neo River to collect Shikamaia fossils, and the Seismic Faults Observation & Experience House to observe Neodani Fault, which ruptured causing the Nobi earthquake in 1891. We successfully made a meaningful field program. The second day began with a lecture on mechanism of earthquake occurrence and fault slipping by Prof. Sagiya. After the lecture, the students studied about natural disasters and their mitigation at the Disaster Mitigation Research Building (Gensai-kan), and took part in a hands-on experiment of making fault by the use of flour and cocoa powder. 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., 名古屋大学宇宙地球環境研究所は、2019年7月31日（水）と8月1日（木）の2日間にわたり、小学校4年生から6年生25名を対象とした夏休み体験学習を実施した。初日は、大型バスをチャーターして、子ども達25名とスタッフ11名、総勢36名で、岐阜県大垣市、本巣市に出向いた。金生山化石館では、高木洋一元館長から化石についての説明を受けた後、古生代の化石であるフズリナやシカマイア（巨大二枚貝）の観察を行った。根尾川河原では、根尾公民館の三本木隆館長のご指導のもと、シカマイア化石の採集を行った。また、根尾谷地震断層観察館・体験館では、1891年の濃尾地震によって形成された根尾谷断層の観察を行い、濃尾地震の揺れを実体験した。2日目は、名古屋大学減災館で、減災連携研究センターの鷺谷威教授から地震発生や断層形成のメカニズム、地震防災について学んだ。その後、研究所共同館Ⅱに移動し、小麦粉とココアを用いた断層形成実験を行った。最後に、体験学習で学んだことを班ごとに話し合ってポスターにまとめ、発表会を行なった。

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．

Electron probe microanalysis (EPMA) is performed using two JCXA-733 (JEOL, Tokyo) for CHIME (chemical Th-U-total Pb isochron method) dating, quantitative EPMA of ultra-trace elements and other geological applications at the Division for Chronological Research, Institute for Space–Earth Environmental Research (ISEE), Nagoya University. X-ray fluorescence spectrometer (XRF-1800, Shimadzu, Kyoto) and X-ray diffractometer (MiniFlex, Rigaku, Tokyo) are also provided for the joint research programs by ISEE in addition to JCXA-733., 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，日本電子株式会社製JCXA-733）を用い，U-Th-Pb系のサブグレン年代測定や極微量元素定量分析を実施している．また，今年度から蛍光エックス線装置（株式会社島津製作所製XRF-1800）およびエックス線回折計（株式会社リガク製MiniFlex）を共同利用・共同研究に供することにした．EPMAのハードディスクを昨年度にFPGAを用いたエミュレーターに置き換えていたが，起動に7分程度かかっていた．今年度はエミュレーターを更新し，ディスクの起動時間を7秒に短縮した．また，フロッピーディスクについてもArduinoを用いたエミュレーターに置き換え，すべての記録メディアを半導体メモリーにすることができた．

This study reveals the crystallization processes of magmatic-origin quartz grains, based on cathodeluminescence (CL) observations, quantitative determinations of titanium concentration and petrography of quartz, as an example of the Tono plutonic complex, Kitakami Mountains. The CL observations provide the patterns of crystallization process of quartz. The CL patterns of quartz are classified into six groups. Patterns A to D with CL zoning structure provide the information of crystallization behavior. Patterns E and F without CL zoning structure do not show the crystallization process. Because the titanium concentration in quartz depends on the crystallization temperature leading the crystallization temperature of quartz by using the TitaniQ geothermometer. In this study, we developed the method of quantitative determination of titanium concentration in quartz by using electron probe microanalysis (EPMA; JEOL JCXA-733) housed at the Institute for Space-Earth Environmental Research (ISEE) , Nagoya University. As the result, the quantitative analysis accompanies the detection limit of 15 ppm and the relative error of about 10%. The quantitative values ranging from 15 to 472 ppm contain the error ranges of 9–14 ppm. Applying the TitaniQ geothermometer for the determined titanium concentration, the crystallization temperatures of quartz range from 561 to 975°C. These procedures contribute to reveal 1) the crystallization process of each quartz grain and 2) the sequences among quartz crystals in sample., 本研究では，カソードルミネッセンス（CL）像解析およびチタン（Ti）濃度定量に岩石記載を組み合わせ，北上山地，遠野複合深成岩体に産出する石英の結晶化プロセスの解明を行った．石英のCL像は，石英の結晶成長の様式の推定に利用可能である．山形大学のSEM-CLを用いて石英のCL像を取得した．その結果，CLパターンは，石英の成長様式を推定可能な4パターンと推定が困難な2パターンに分類した．石英中のTi濃度は，石英の結晶化する温度に依存するため，石英の結晶化温度の推定に利用できる（Wark and Watson, 2006）．しかし，石英に含有されるTiはごく微量で，EPMAでの一般的な分析条件では定量が困難である．そこで本研究では，名古屋大学ISEEのEPMA（JEOLJCXA-733）を用い，石英中のTi濃度の高精度定量分析法の開発を行った．その結果，Tiの検出限界は15ppm，分析値16－472ppmに対して誤差は9－14ppmの精度で定量値を取得することが可能となった．これは，石英結晶内部のTi濃度の高精度な比較を可能にする．この手法によるTi濃度定量に，CL像観察，岩石記載を組み合わせることで，1）個々の石英粒子の結晶化プロセス，2）石英粒子同士の晶出順序の解明を行った．

Biogenic graphite in > 3.7 Ga metasediments, Isua Supracrustal Belt (ISB), West Greenland, has been reported as the oldest remnants of life. However, ecosystem spreaded in the >3.7Ga ocean is still poorly understood. Isua biogenic graphite is located in chlorite-rich layers of metasediments as grains accompanied by monazite, xenotime and zircon. These rare earth element (REE)-bearing minerals could be supplied to sediments at primary sedimentary setting or precipitated from metamorphic fluids. Chemical Th-U-total Pb Isochron Method (CHIME) dating was conducted on these REE-bearing minerals to constraint the generation process. CHIME age of zircon in graphite-rich metasediments indicates 3.9−3.8 Ga, which is consistent with previous zircon age in banded iron formation collected close to our sampling area. CHIME age of monazite and xenotime indicate two age peaks of ~2.7 Ga and ~3.7 Ga. Previous studies suggest that Isua retrograde metamorphism has occurred at ~2.7 Ga (Frei et al., 2001), which is consistent with one of age peaks of monazite and xenotime. Nano-scale observation of monazite by transmission electron microscope showed that well-ordered, sheeted graphite was crystalized around monazite, whereas quartz and disordered graphite were observed as inclusion of monazite. Considering with CHIME results and nano-structures of monazite together, monazite was considered to be formed during early diagenesis with involving indigenous biogenic organic matter and quartz and suffered by subsequent metamorphic events. The occurrence of monazite resembles REE-bearing minerals observed in Australian Archaean sedimentary rocks reported by Rasmussen (1996), which could be derived from altered biogenic organic matter during diagenesis., 最古の生命の痕跡は約38億年前の岩石が分布するグリーンランド・イスア表成岩帯で発見されているが，当時どのような微生物圏が地球表層に広がっていたのか詳細は不明である．本研究では，生物由来グラファイトと共存するモナザイトやゼノタイム，ジルコンのCHIME年代測定から，これらの鉱物の成因に制約を与えることを目的とした．分析の結果，ジルコンの形成年代は39～38億年前を示したのに対して，ゼノタイム及びモナザイトは約37億年前と約27億年前の2箇所にピークを持つことがわかった．また，電子顕微鏡観察結果から，モナザイトが欠陥の多いグラファイトや石英を包有していることがわかった．以上のことから，モナザイトは生物由来の有機物や周辺の石英を取り込みながら結晶化した可能性が挙げられる．しかしながらCHIME測定の成功率は低く未だ十分なデータ量が得られていないため，測定成功率を上げるべく試料準備に更なる工夫が必要と考えられる．

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．

2台の電子プローブマイクロアナライザー（EPMA,日本電子株式会社JCXA-733）を用い，名古屋大学宇宙地球環境研究所ではCHIME年代測定や極微量元素EPMA定量分析を実施している．これまで旧式のディスクドライブを使用していたが，2017年度にFPGAを用いたエミュレーターで置き換え，メディアをmicroSDカードにした．これにより，小型化，省電力化を実現した．