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Geochemical characterization of monazite sands in placer deposit from Kanyakumari southern coast of Tamil Nadu, India: Implication of Uranium isotope ratios and high content of rare earth elements
https://repo.qst.go.jp/records/80350
https://repo.qst.go.jp/records/80350d7544e2f-e535-4239-bf98-a40812a7beba
| Item type | 会議発表用資料 / Presentation(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2020-08-21 | |||||
| タイトル | ||||||
| タイトル | Geochemical characterization of monazite sands in placer deposit from Kanyakumari southern coast of Tamil Nadu, India: Implication of Uranium isotope ratios and high content of rare earth elements | |||||
| 言語 | ||||||
| 言語 | eng | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_c94f | |||||
| 資源タイプ | conference object | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
Veerasamy , Nimelan
× Veerasamy , Nimelan× Kasar, Sharayu× Murugan, Rajamanickam× Kavasi, Norbert× Inoue, Kazumasa× Fukushi , Masahiro× Kumar Sahoo, Sarata× Nimelan, Veerasamy× Kasar, Sharayu× Murugan, Rajamanickam× Kavasi, Norbert× Sahoo, Sarata |
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| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | Kanyakumari region in southern coast of Tamil Nadu, India is a well-known natural high background radiation area due to the abundances of monazite in the beach placer deposits. Natural gamma dose rate measurements were carried out covering an area of 50 km along the coastal belt. The ambient dose rate varied from 65 nGy h-1 to 25.5 Gy h-1. Based on the ambient dose rate 23 locations were selected for sand sample collection. The main aim of the study is to understand radiological as well as geochemical characterization of placer deposit. Monazite is an ore mineral for Th with relatively high concentration of Ce, Nd and U. The activity concentration of 226Ra, 228Ac and 40K were measured by a High purity Ge gamma spectroscopy and associated radiological hazard parameters were estimated. The concentration of major oxides and U, Th and REEs were measured using XRF and ICP-MS respectively. TiO2 and Fe2O3 concentrations are high compared to average upper continental crust. High TiO2 could be attributed to the presence of ilmenite in the sands. Average ƩREE concentration in sand samples is about thirty times higher than the average crustal concentration. The LREE/HREE is greater than 1 with negative Eu anomaly, it could be either felsic or granitic source. On the other hand, Th/U ratio ranged from 8 to 24 which clearly indicates Th is the dominant radionuclide for the enhanced natural radioactivity in the environment. The concentration of U varied from 18 to 230 g g-1. The 234U/238U and 235U/238U isotope ratios were measured by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). However, the activity ratio of U ranged from 0.97 to 1.06 in the samples. The detail information will be discussed during presentation. | |||||
| 会議概要（会議名, 開催地, 会期, 主催者等） | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | VII. Terrestrial Radioisotopes in Environment International Conference on Environmental Protection, 10-13 AUGUST, 2020 (TREICEP 2020) | |||||
| 発表年月日 | ||||||
| 日付 | 2020-08-11 | |||||
| 日付タイプ | Issued | |||||
