Sr isotope ratio in vegetable crops and apple trees depends on that of the soil environment while is unaffected by the genotype

The 87Sr/86Sr ratio is an effective geographical tracer for horticultural products. In plants this ratio reflects closely the characteristics of the growing area. However, information about the variability of this parameter when measured in different plant species or cultivars is still scarce. In this work, we have tested the hypothesis that, when plants are growing in the same environment, their 87Sr/86Sr ratio is independent from the plant species or cultivar. For this, four to six vegetable species were collected from two fields in different locations in South Tyrol (Italy), together with the corresponding soils. Additionally, within a single apple orchard located in the same area, apple leaves were collected from trees of five cultivars. The 87Sr/86Sr ratio was measured applying an established and validated method. In general, vegetable species growing in the same field had similar 87Sr/86Sr ratios and showed a lower variability compared to their corresponding soils, while a significant difference was found comparing the 87Sr/86Sr ratios of the two vegetable fields. Apple leaves sampled from different tree cultivars also did not show a significant difference in their 87Sr/86Sr ratio. We concluded that the 87Sr/86Sr ratio in vegetables and apple trees was affected by the soil, but not significantly by the type of species or cultivar. Therefore, within limited areas, the results of the 87Sr/86Sr ratio analysis based on samples of a certain species/cultivar can be extended to other similar plants growing in the same site.

Specificity and Origin of the Stability of the Sr Isotopic Ratio in Champagne Wines

The 87Sr/86Sr ratio of 39 Champagnes from six different brands, originating from the whole “Appellation d’Origine Contrôlée” (AOC) Champagne was analyzed to establish a possible relation with the geographical origin. Musts (i.e., grape juice) and base wines were also analyzed to study the evolution of the Sr isotopic ratio during the elaboration process of sparkling wine. The results demonstrate that there is a very homogeneous Sr isotopic ratio (87Sr/86Sr = 0.70812, n = 37) and a narrow span of variability (2σ = 0.00007, n = 37). Moreover, the Sr concentrations in Champagnes have also low variability, which can be in part explained by the homogeneity of the bedrock in the AOC Champagne. Measurements of the 87Sr/86Sr ratio from musts and base wines show that blending during Champagne production plays a major role in the limited variability observed. Further, the 87Sr/86Sr of the musts were closely linked to the 87Sr/86Sr ratio of the vineyard soil. It appears that the 87Sr/86Sr of the product does not change during the elaboration process, but its variability decreases throughout the process due to blending. Both the homogeneity of the soil composition in the Champagne AOC and the blending process during the wine making process with several blending steps at different stages account for the unique and stable Sr isotopic signature of the Champagne wines.

The Provenance of Slovenian Milk Using 87Sr/86Sr Isotope Ratios

This work presents the first use of Sr isotope ratios for determining the provenance of bovine milk from different regions of Slovenia. The analytical protocol for the determination of 87Sr/86Sr isotope ratio was optimised and applied to authentic milk samples. Considerable variability of 87Sr/86Sr ratios found in Slovenian milk reflects the substantial heterogeneity of the geological background of its origin. The results, although promising, cannot discount possible inter-annual or annual variation of the Sr isotopic composition of milk. The 87Sr/86Sr ratios of groundwater and surface waters are in good correlation with milk, indicating that the Sr isotopic fingerprint in milk is reflective of cow drinking water. The 87Sr/86Sr ratio has the potential to distinguish between different milk production areas as long as these areas are characterised by geo-lithology. Discriminant analysis (DA) incorporating the elemental composition and stable isotopes of light elements showed that 87Sr/86Sr ratio together with δ13Ccas and δ15Ncas values have the main discrimination power to distinguish the Quaternary group (group 6) from the others. Group 1 (Cretaceous: Carbonate Rocks and Flysch) is associated with Br content, 1/Sr and δ18Ow values. The overall prediction ability was found to be 63.5%. Pairwise comparisons using OPLS-DA confirmed that diet and geologic parameters are important for the separation.

Origin of Drusy Dolomite Cement in Permo-Triassic Dolostones, Northern United Arab Emirates

While the characteristics and origin of drusy calcite cement in carbonate deposits is well constrained in the literature, little attention is paid to drusy dolomite cement. Petrographic observations, stable isotopes, and fluid-inclusion microthermometry suggest that drusy dolomite cement in Permo-Triassic conglomerate/breccia dolostone beds in northern United Arab Emirates has precipitated as cement and not by dolomitization of drusy calcite cement. The low 18OVPDB (−9.4‰ to −6.2‰) and high homogenization temperatures of fluid inclusions in drusy dolomite (Th = 73–233 °C) suggest that dolomitization was caused by hot basinal brines (salinity = 23.4 wt% NaCl eq.). The 13CVPDB values (+0.18‰ to +1.6‰) and 87Sr/86Sr ratio (0.708106 to 0.708147) indicate that carbon and strontium were derived from the host marine Permo-Triassic carbonates. Following this dolomitization event, blocky calcite (Th = 148 °C; salinity = 20.8 wt% NaCl eq.) precipitated from the hot basinal brines. Unravelling the origin of drusy dolomite cement has important implications for accurate construction of paragenetic sequences in carbonate rocks and decipher the origin and chemistry of diagenetic waters in sedimentary basins.

Sr Isotope Chemostratigraphy and Pb–Pb Age of the Riphean Carbonate Deposits of the Kharaulakh Uplift (Northeastern Margin of the Siberian Platform)

—The least altered limestones of the Ukta and Eselekh formations in the Precambrian section of the Kharaulakh uplift have a minimum 87Sr/86Sr ratio of 0.70673–0.70715. The lowest 87Sr/86Sr ratio of the overlying Neleger and Sietachan formations is 0.70791–0.70817. Based on these data, along with the earlier obtained positive δ13С values (up to 8‰) for the Kharaulakh section, we have estimated the age of the Ukta and Eselekh formations at 800–670 Ma and the age of the Neleger and Sietachan formations at ~640–580 Ma. The Pb–Pb isochron age of the least altered limestones of the Eselekh Formation calculated from eight samples is 720 ± 30 Ma. This age permits us to define the lower part of the Kharaulakh section of the Ukta and Eselekh formations to be the late Tonian of the International Chronostratigraphic Chart or to the Upper Riphean of the General Stratigraphic Scale of Russia. The presence of reliably dated Upper Riphean sediments in the Kharaulakh uplift indicates a more complex structure of the Precambrian sedimentary cover on the Arctic margin of the Siberian Platform than assumed earlier.

BRONZE AGE TEXTILE FROM THE CHESMENKA 3 KURGAN GROUP IN THE VORONEZHREGION: TECHNOLOGY, ISOTOPIC COMPOSITION AND RADIOCARBON CHRONOLOGY

Статья посвящена анализу сложного аксессуара, найденного в могильнике Чесменка 3, курган 2, погребение 4. Для изготовления многокомпонентного изделия использовались материалы разного происхождения: войлок, на который льняными нитями были пришиты пронизи, нанизанные на шерстяные нити. Радиоуглеродное датирование фрагмента льняной нити позволило отнести захоронение ранней покровской культуры к 1800–1700 гг. до н. э. Определение вариаций отношений стронция 87Sr/86Sr во фрагменте льняного шнура и сравнительный анализ с фоновыми «изотопными метками» указывают на возможные западные ареалы происхождения растительного сырья. Использование шерстяных нитей и войлока соотносится с хронологией и траекторией распространения шерстяного волокна и шерстяных тканей в начале II тыс. до н. э. из южных регионов Кавказа и прилегающей степи на север. The paper analyzes a composite accessory discovered in the Chesmenka 3 cemetery, kurgan 2, grave 4. Various materials were used to make the item. It consists of several components such as felt, tubular beads strung on wool threads and sewn onto the felt with a linen thread. Radiocarbon dating of linen thread fragment helped relate this grave to the early Pokrovka culture (1800–1700 BC). The variation in the 87Sr/86Sr ratio in the linen thread fragment and comparative analysis with the use of background «isotopic signatures» point to likely western areas of plant raw material sources. The use of wool fibers and woolen cloths correlates with the chronology and the distribution pattern of wool fibers and wool cloths in the early second millennium BC, i.e. from the southern areas of the Caucasus and the adjacent steppes to the north.

Using Isotopes (H, O, and Sr) and Major Ions to Identify Hydrogeochemical Characteristics of Groundwater in the Hongjiannao Lake Basin, Northwest China

Hongjiannao Lake is the largest desert freshwater lake in the Ordos Plateau, China, and the relict gull is an endangered species that uses the lake for its habitat, with the largest colonies being located there. Using hydrochemical parameters, stable hydrogen and oxygen isotopes, and strontium isotopes, we investigated the hydrogeochemical characteristics of groundwater. As a result, the major cations of the groundwater were found to be Ca2+ and Na+, the major anion was found to be HCO3−, and the hydrochemical facies were mainly found to be HCO3–Ca, HCO3–Na. and HCO3–Ca–Na. The hydrochemical formation of groundwater was controlled by both evaporation and water–rock interactions, and carbonate and sulfate minerals dissolved or precipitated in the groundwater. On the basis of isotope analysis, groundwater was affected by evaporation and δ18O enrichment, and the higher salinity of Hongjiannao Lake suffered from intensive evaporation. The higher 87Sr/86Sr ratio and lower concentrations of Sr2+ in the groundwater were derived from the dissolution of silicate minerals, whereas the opposite concentrations were due to the dissolution of carbonate and sulfate minerals. Based on this work, such results can be used to research groundwater recharge into the lake and to protect water quality.

Sulfide Rb-Sr, Re-Os and In Situ S Isotopic Constraints on Two Mineralization Events at the Large Hongnipo Cu Deposit, SW China

The Hongnipo deposit, a newly discovered large copper deposit in the Kangdian copper belt, SW China, is hosted in the Paleoproterozoic Hekou Group. This deposit contains ~4200 Mt of Cu ores, with an average grade of 1.42 wt.% Cu. Orebodies occur mainly as stratiform, stratoid and lenticular forms. Mineralization consists predominantly of high grade vein-type ores and low grade laminated ores. Field relationships indicate vein-type mineralization crosscuts laminated mineralization and host rocks, indicating that there were at least two mineralization events during the formation of the deposit. Pyrite separates from the laminated ores yield a Rb-Sr isochron age of 1552 ± 80 Ma, with a highly radiogenic initial 87Sr/86Sr ratio of 0.71214 ± 0.00081, indicating a major contribution from the ore-hosting rocks. Sulfides from the laminated ores have δ34S values ranging from −1.8‰ to 11.4‰, with the vast majority in the range of 5.3‰ to 11.4‰, suggesting the mixed derivation of sulfur from seawater sulfates and magmatic fluids. Chalcopyrite separates from the vein-type ores have a Re-Os isochron age of 794.8 ± 7.9 Ma. The initial 187Os/188Os (2.8 ± 1.2) and γOs (+2202) values are slightly lower than the average values of continental crust, indicating a major metal source of the Hekou Group with minor mantle input. Sulfides from the vein-type ores have δ34S values that range from −10.3‰ to 4.0‰ and cluster between 0‰ to 2.2‰, which implies a significant contribution of magmatic-sourced sulfur with minor biogenic sulfur. Two major mineralization events have been identified. The Rb-Sr age of the laminated ores likely records a VMS mineralization event at ~1.6 Ga. The much younger Re-Os age is considered to represent the timing of an important mineralization event, which is likely related to the Neoproterozoic magmatism and/or metamorphism and represents a newly documented mineralization event to be targeted by exploration.