87Sr/86Sr ISOTOPE RATIOS IN THE RIVER WATERS OF THE SOUTHERN URALS

87Sr/86Sr isotopic ratios are widely used to identify strontium sources and study strontium behaviour in (bio)geochemical cycles. 87Sr/86Sr in surface waters can reflect the average composition of bioavailable (i.e. available for further absorption by plants and animals) strontium in the catchment specific area. Based on those 87Sr/86Sr ratios, the regional maps of the bioavailable strontium distribution (strontium isoscapes) can be compiled. A complex block structure characterizes the Ural mountain system. Individual parts (blocks) are composed of rocks of various ages, genesis and geochemical characteristics, which can radically change at a distance of several tens of kilometres. Such variability would be reflected in strontium isotopic ratios, thus making it possible to determine the local isotopic signatures of bioavailable strontium. This work aimed to study 87Sr/86Sr in the water in the rivers of the Southern Urals. We determined the contents and isotopic ratios of strontium in river water samples collected from the territories of the Orenburg and Chelyabinsk regions and the Republic of Bashkortostan in 2019-2020. For the first time in the surface water of the rivers in the Southern Urals (Ural, Belaya, Tobol, Karagaily-Ayat, Sim, and others), the 87Sr/86Sr isotopic ratios have been determined, and their variations have been analyzed. 87Sr/86Sr values vary in the range 0.70666-0.71063 (average 0.70908) for the rivers of the Urals basin, 0.70749-0.71058 (average 0.70924) for the Kama-Volga basin, 0.70946-0.71176 (average 0.71071) for the Tobol basin. Such features of the strontium isotopic composition may be due to the influence of underlying rocks of the catchment area drained by river water. The data obtained can be used to identify the sources of strontium input into the water system during hydrological and environmental studies; to confirm the authenticity of food products of plant and animal origin; to carry out comparisons in the studies of the migration of ancient people and animals, as well as to determine the raw material areas for the production of vegetable and woollen textiles and wooden products in antiquity. © 2022 Institute of the Earth's Crust. All rights reserved.Russian Foundation for Basic Research, РФФИ: 20-09-00194; Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2021-680The study is supported by the Russian Foundation for Basic Research (project 20-09-00194) and performed within the state task of the IGG UB RAS АААА-А18-118053090045-8 at the "Geoanalitik" shared research facilities of the IGG UB RAS. The re-equipment and comprehensive development of the "Geoanalitik" shared research facilities of the IGG UB RAS is financially supported by the grant of the Ministry of Science and Higher Education of the Russian Federation (Agreement 075-15-2021-680).FUNDING: The study is supported by the Russian Foundation for Basic Research (project 20-09-00194) and performedwithin the state task of the IGG UB RAS АААА-А 猃稁猃猃稃爃眃甃爃? 爃爃瘃省稀 at the 㘀Geoana?itik 㘀 shared research faci?ities of the IGG UB RAS. The re-equipment and comprehensive deve?opment of the 㘀Geoana?itik 㘀 shared research faci?ities of the IGG UB RAS is 퀀inancia??y supported by the grant of the Ministry of Science and Higher Education of the Russian Federation (Agreement 075-15-2021-680)

Assessment of Heavy Metal Contamination of Surface Waters, Soils and Plants in the Orenburg Region

Microelement analysis of surface waters, soils and plants from the Orenburg region was carried out. For V, Cr, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sn, Sb, and Pb a comparison was made with the threshold limit values in drinking water, and the enrichment factors were calculated.Работа поддержана РФФИ (проект № 20-09-00194) и выполнена в ЦКП «Геоаналитик» ИГГ УрО РАН в рамках темы № АААА-А18-118053090045-8 государственного задания ИГГ УрО РАН. Дооснащение и комплексное развитие ЦКП «Геоаналитик» ИГГ УрО РАН осуществляется при финансовой поддержке гранта Министерства науки и высшего образования Российской Федерации, Соглашение № 075-15-2021-680

ИЗОТОПНЫЕ ОТНОШЕНИЯ СТРОНЦИЯ 87Sr/86Sr В ВОДЕ РЯДА РЕК ЮЖНОГО УРАЛА

87Sr/86Sr isotopic ratios are widely used to identify strontium sources and study strontium behaviour in(bio)geochemical cycles. 87Sr/86Sr in surface waters can reflect the average composition of bioavailable (i.e. available forfurther absorption by plants and animals) strontium in the catchment specific area. Based on those 87Sr/86Sr ratios, theregional maps of the bioavailable strontium distribution (strontium isoscapes) can be compiled. A complex block structurecharacterizes the Ural mountain system. Individual parts (blocks) are composed of rocks of various ages, genesis andgeochemical characteristics, which can radically change at a distance of several tens of kilometres. Such variability wouldbe reflected in strontium isotopic ratios, thus making it possible to determine the local isotopic signatures of bioavailablestrontium.This work aimed to study 87Sr/86Sr in the water in the rivers of the Southern Urals. We determined the contents andisotopic ratios of strontium in river water samples collected from the territories of the Orenburg and Chelyabinsk regionsand the Republic of Bashkortostan in 2019–2020.For the first time in the surface water of the rivers in the Southern Urals (Ural, Belaya, Tobol, Karagaily-Ayat, Sim, andothers), the 87Sr/86Sr isotopic ratios have been determined, and their variations have been analyzed. 87Sr/86Sr values varyin the range 0.70666–0.71063 (average 0.70908) for the rivers of the Urals basin, 0.70749–0.71058 (average 0.70924)for the Kama-Volga basin, 0.70946–0.71176 (average 0.71071) for the Tobol basin. Such features of the strontium isotopiccomposition may be due to the influence of underlying rocks of the catchment area drained by river water. The dataobtained can be used to identify the sources of strontium input into the water system during hydrological and environmentalstudies; to confirm the authenticity of food products of plant and animal origin; to carry out comparisons in thestudies of the migration of ancient people and animals, as well as to determine the raw material areas for the productionof vegetable and woollen textiles and wooden products in antiquity.Изотопные отношения стронция 87Sr/86Sr широко используются для выявления источниковстронция и исследования его поведения в (био)геохимических циклах, а в поверхностных водах они могут отражатьусредненный состав биодоступного (доступного для дальнейшего поглощения растениями и животными)стронция на конкретной территории водосбора, на основании чего могут быть составлены региональные картыраспределения биодоступного стронция (Sr изоскейпы). Уральская горная система характеризуется блочнойструктурой, отдельные части (блоки) которой сложены разнообразными по возрасту, генезису и геохимическимособенностям горными породами, которые могут радикально изменяться на расстоянии нескольких десятковкилометров. Такая вариативность будет отражаться и в изотопных отношениях стронция, что позволит с достаточновысокой точностью определить локальные метки биодоступного стронция.Целью работы являлось исследование изотопных отношений стронция 87Sr/86Srв воде ряда рек Южного Урала.В образцах речной воды, отобранных в 2019–2020 гг. с территорий Оренбургской и Челябинской областей и РеспубликиБашкортостан, определены содержания (квадрупольная масс-спектрометрия с индуктивно связаннойплазмой) и изотопные отношения стронция (мультиколлекторная масс-спектрометрия с индуктивно связаннойплазмой и термоионизационная масс-спектрометрия после хроматографического выделения стронция).Впервые в поверхностной воде ряда рек Южного Урала (Урал, Белая, Тобол, Карагайлы-Аят, Сим и др.) определеныизотопные отношения 87Sr/86Sr и проанализированы их вариации. Для рек бассейна р. Урал значения87Sr/86Sr варьируются в диапазоне 0.70666–0.71063 (среднее 0.70908), для бассейна р. Кама – 0.70749–0.71058(среднее 0.70924), для бассейна р. Тобол – 0.70946–0.71176 (среднее 0.71071). Подобные особенности изотопногосостава стронция могут быть обусловлены типом подстилающих горных пород водосбора, дренируемых речнойводой. Полученные данные могут быть использованы для выявления источников поступления стронция в воднуюсистему при гидрологических и экологических исследованиях, для подтверждения аутентичности пищевыхпродуктов растительного и животного происхождения, для проведения сопоставлений при исследованияхмиграций древних людей и животных, а также для определения сырьевых ареалов для производства растительногои шерстяного текстиля, деревянных изделий в древности

⁸⁷Sr/⁸⁶Sr ISOTOPE RATIOS IN THE RIVER WATERS OF THE SOUTHERN URALS

87Sr/86Sr isotopic ratios are widely used to identify strontium sources and study strontium behaviour in(bio)geochemical cycles. 87Sr/86Sr in surface waters can reflect the average composition of bioavailable (i.e. available forfurther absorption by plants and animals) strontium in the catchment specific area. Based on those 87Sr/86Sr ratios, theregional maps of the bioavailable strontium distribution (strontium isoscapes) can be compiled. A complex block structurecharacterizes the Ural mountain system. Individual parts (blocks) are composed of rocks of various ages, genesis andgeochemical characteristics, which can radically change at a distance of several tens of kilometres. Such variability wouldbe reflected in strontium isotopic ratios, thus making it possible to determine the local isotopic signatures of bioavailablestrontium.This work aimed to study 87Sr/86Sr in the water in the rivers of the Southern Urals. We determined the contents andisotopic ratios of strontium in river water samples collected from the territories of the Orenburg and Chelyabinsk regionsand the Republic of Bashkortostan in 2019–2020.For the first time in the surface water of the rivers in the Southern Urals (Ural, Belaya, Tobol, Karagaily-Ayat, Sim, andothers), the 87Sr/86Sr isotopic ratios have been determined, and their variations have been analyzed. 87Sr/86Sr values varyin the range 0.70666–0.71063 (average 0.70908) for the rivers of the Urals basin, 0.70749–0.71058 (average 0.70924)for the Kama-Volga basin, 0.70946–0.71176 (average 0.71071) for the Tobol basin. Such features of the strontium isotopiccomposition may be due to the influence of underlying rocks of the catchment area drained by river water. The dataobtained can be used to identify the sources of strontium input into the water system during hydrological and environmentalstudies; to confirm the authenticity of food products of plant and animal origin; to carry out comparisons in thestudies of the migration of ancient people and animals, as well as to determine the raw material areas for the productionof vegetable and woollen textiles and wooden products in antiquity