litosphereЛитосфераLITHOSPHERE (Russia)1681-90042500-302XA.N. Zavaritsky Institute of Geology and Geochemistry10.24930/1681-9004-2024-24-2-364-375litosphere-2070Research ArticleСтатьиArticlesРеализация и опыт использования в ЦКП “Геоаналитик” методик анализа изотопного состава Sm и Nd, Rb и Sr в образцах породImplementation and experience of using methods for analyzing the isotopic composition of Sm and Nd, Rb and Sr in rock samples at the Geoanalitik Center for Collective UseСолошенкоН. Г.SoloshenkoN. G.

620110, г. Екатеринбург, ул. Академика Вонсовского, 15

Natalia G. Soloshenko

15 Academician Vonsovsky st., Ekaterinburg 620110

soloshenko@igg.uran.ruСтрелецкаяМ. В.StreletskayaM. V.

620110, г. Екатеринбург, ул. Академика Вонсовского, 15

Maria V. Streletskaya

15 Academician Vonsovsky st., Ekaterinburg 620110

ЧервяковскаяМ. В.ChervyakovskayaM. V.

620110, г. Екатеринбург, ул. Академика Вонсовского, 15

Maria V. Chervyakovskaya

15 Academician Vonsovsky st., Ekaterinburg 620110

КиселеваД. В.KiselevaD. V.

620110, г. Екатеринбург, ул. Академика Вонсовского, 15

Daria V. Kiseleva

15 Academician Vonsovsky st., Ekaterinburg 620110

Институт геологии и геохимии им. академика А.Н. Заварицкого УрО РАНРоссияA.N. Zavaritsky Institute of Geology and Geochemistry, UB RASRussian Federation202407052024242364375Copyright © Солошенко Н.Г., Стрелецкая М.В., Червяковская М.В., Киселева Д.В., 20242024Солошенко Н.Г., Стрелецкая М.В., Червяковская М.В., Киселева Д.В.Soloshenko N.G., Streletskaya M.V., Chervyakovskaya M.V., Kiseleva D.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.lithosphere.ru/jour/article/view/2070

Объекты исследования. Международные образцы сравнения для изучения изотопных систем Sm, Nd и Rb, Sr (AGV-2, BHVO-2); минеральные образцы – разнообразные породы и минералы. Методы. Анализ изотопного состава Sm, Nd и Rb, Sr проведен с использованием масс-спектрометров NeptunePlus и TritonPlus. Цель. Реализация методик анализа изотопного состава Sm и Nd, Rb и Sr в минеральных образцах (разнообразных породах и минералах) с использованием двух типов масс-спектрометров – многоколлекторного с индуктивно связанной плазмой NeptunePlus и с термической ионизацией TritonPlus (ThermoFisher), а также описание процедуры обработки экспериментальных данных и опыта применения методик в ЦКП “Геоаналитик” за период 2015–2023 гг. Результаты. Реализованные аналитические методики включали: 1) хроматографическую подготовку в колонках различного размера с использованием различных смол, оптимизированную по соотношению трудозатраты/качество результатов анализа; 2) измерение изотопных отношений на двух типах масс-спектрометров; 3) коррекцию масс-дискриминации результатов измерений изотопных отношений и определение концентраций Sm и Nd, Rb и Sr методом изотопного разбавления с применением изотопной метки смесей 149Sm + 150Nd и 85Rb + 84Sr. Апробация методик выполнена на ряде международных образцов сравнения AGV-2, BHVO-2; представлены их метрологические характеристики. При использовании МС TritonPlus воспроизводимость (BHVO-2, n = 60) измерения изотопных отношений 143Nd/144Nd, 147Sm/144Nd и концентраций Sm и Nd составляют ±0.000020, ±0.0004, ±1.3, ±0.4 соответственно; показатели правильности определения отношений 143Nd/144Nd и 147Sm/144Nd – 0.001 и 0.25%, концентраций Sm и Nd – 2%; воспроизводимость (BHVO-2, n = 63) измерения изотопных отношений 87Sr/86Sr, 87Rb/86Sr и концентраций (Rb и Sr) составляют ±0.0025, ±1.5, ±2%, соответственно. Неопределенность единичного измерения изотопного отношения 143Nd/144Nd и 87Sr/86Sr, представленная стандартной ошибкой среднего единичного измерения в образце, достигает не более 0.0025%. Выводы. Полученные результаты по образцам сравнения удовлетворительно согласуются с таковыми в базе GeoReM, а также с сертифицированными значениями производителя стандартов – Геологической Службы США (USGS). Описанные методики анализа применялись в ЦКП “Геоаналитик” для выполнения анализов разнообразных проб пород и минералов; в работе представлен ряд полученных экспериментальных результатов, которые в дальнейшем использованы при геохронологических построениях.

Research subject. AGV-2 and BHVO-2 geochemical reference materials for studying the Sm, Nd and Rb, Sr isotope systems along with various rocks and mineral samples. Materials and Methods. An analysis of the isotopic composition of Sm, Nd and Rb, Sr was carried out using Neptune Plus and Triton Plus mass spectrometers. Aim. To implement analytical techniques for the isotopic composition of Sm and Nd, Rb, and Sr in various rock and mineral samples using two types of multicollector mass spectrometers – inductively coupled plasma NeptunePlus and thermal ionization TritonPlus (Thermo-Fisher), as well as a description of the procedure of processing experimental data and the experience in using techniques at the “Geoanalitik” shared research facilities of the IGG UB RAS for the period 2015-2023. Results. The analytical techniques implemented included (1) column chromatography using various ion-exchange resins, optimised for the ratio of labour costs/quality of analytical results; (2) the measurement of isotope ratios using two types of mass spectrometers; (3) the correction of mass bias of isotope ratios and the determination of Sm and Nd, Rb, and Sr concentrations by the isotope dilution method using 149Sm+150Nd and 85Rb+84Sr spikes. Testing of the techniques was carried out using the AGV-2 and BHVO-2 geochemical reference materials; their metrological characteristics were presented. When using TritonPlus, the reproducibility (BHVO-2, n=60) of measurements of 143Nd/144Nd, 147Sm/144Nd isotope ratios and Sm and Nd concentrations are ±0.000020, ±0.0004, ±1.3 and ±0.4, respectively; indicators of correctness of determining the ratios 143Nd/144Nd and 147Sm/144Nd – 0.001 and 0.25% and concentrations of Sm and Nd – 2%; the reproducibility (BHVO-2, n=63) of measurements of 87Sr/86Sr, 87Rb/86Sr isotope ratios and concentrations (Rb and Sr) are ±0.0025%, ±1.5%, ±2%, respectively. The uncertainty of a single measurement of the 143Nd/144Nd and 87Sr/86Sr isotope ratio, represented by the standard error of the average single measurement in the sample, does not exceed 0.0025%. Conclusions: the results obtained for the geochemical reference materials are in satisfactory agreement with those provided in the GeoReM database, as well as with the certified values provided by the United States Geological Survey (USGS). The described analytical techniques are used at the “Geoanalitik” shared research facilities of the IGG UB RAS to analyse various rock and mineral samples. The work presents a number of experimental results obtained, which are subsequently used in geochronological applications.

самарийнеодимизотопный анализизотопное разбавлениехроматографияsamariumneodymiumisotope analysisisotope dilutionchromatographyРабота выполнена в ЦКП УрО РАН “Геоаналитик” в рамках темы № 123011800012-9 государственного задания ИГГ УрО РАН. Авторы признательны С.Л. Вотякову за инициирование работы, полезное обсуждение результатов и редактирование текста, Ю.О. Ларионовой и К.Н. Шатагину – за передачу опыта и полезное обсуждение результатов, Ю.Л. Ронкину – за предоставление растворов смешанных изотопных меток, анонимным рецензентам – за конструктивные замечания, которые способствовали улучшению рукописи.The work was carried out at the Geoanalitik Center for Collective Use of the Zavaritsky Institute of Geology and Geochemistry, Ural Branch, Russian Academy of Sciences (IGG UB RAS), Yekaterinburg, Russia as part of the state assignment of the IGG UB RAS No. 123011800012-9. The authors are grateful to S.L. 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The authors declare that there are no conflicts of interest present.