Precise determination of lead isotope ratios by MCICP-MS without matrix separation exemplified by unique samples of diverse origin and history

final_author38Narodowe Centrum Naukowe - OPUS 21NCN-OPUS 21 No 2021/41/B/ST4/04231NCN-OPUS 21 No 2021/41/B/ST4/02860Zastosowanie modelu ORM do precyzyjnego oznaczania stosunków izotopowych pierwiastkówAnaLIza spektralna zabytkowych atrameNtów z wykorzystaniem uczenia mAszynowego: ALiN

Application of multicollector mass spectrometry and laser ablation in the study of magnesium isotopes fractionation phenomenon during transport through an ion-selective membrane

final_author228at_publicationNarodowe Centrum NaukiNCN - PRELUDIUM 20 No. 2021/41/N/ST4/03218NCN - MINIATURA 6 No. 2022/06/X/ST4/00343Rozcieńczenia izotopowe jako sposób weryfikacji metody przygotowania próbki w bioobrazowaniu tkanek miękkich metodą LA-ICP-M

Selected isotope ratio measurements of light metallic elements (Li, Mg, Ca, and Cu) by multiple collector ICP-MS

The unique capabilities of multiple collector inductively coupled mass spectrometry (MC-ICP-MS) for high precision isotope ratio measurements in light elements as Li, Mg, Ca, and Cu are reviewed in this paper. These elements have been intensively studied at the Geological Survey of Israel (GSI) and other laboratories over the past few years, and the methods used to obtain high precision isotope analyses are discussed in detail. The scientific study of isotopic fractionation of these elements is significant for achieving a better understanding of geochemical and biochemical processes in nature and the environment

Ca isotope constraints on chemical weathering processes: evidence from headwater in the Changjiang River, China

This study aims to clarify the relationship between chemical weathering of rocks and the carbon budget of rivers and better understand the weathering mechanisms of plateau watersheds. We chose to study the Jinsha River, which originates from the Tibetan Plateau and also is in the upper reaches of the Changjiang River. Analysis of hydrochemistry, radiogenic strontium isotope and stable calcium isotopes were conducted of the Jinsha River water samples, which were collected along its mainstream and main tributaries in the summer. The results show that the water chemistry of the mainstream waters is dominated by evaporite weathering, which have low 87Sr/86Sr values (0.7098–0.7108) and wide range of Sr contents (2.70–9.35 μmol/L). In contrast, tributaries of the Jinsha River have higher 87Sr/86Sr (0.7090–0.7157) and lower Sr contents (∼1 μmol/L). Moreover, the Ca isotopic compositions in the mainstream (0.87–1.11‰) are heavier than the tributaries (0.68–0.88‰) and could not be fully explained by the conventional mixing of different sources. We suggest that secondary carbonate precipitation fractionates Ca isotopes in the Jinsha River, and fractionation factors are between 0.99935 and 0.99963. At least 66% of Ca was removed in the mainstream of the Jinsha River through secondary mineral precipitation, and the average value is ∼35% in the tributaries. The results highlight that evaporite weathering results in more carbonate precipitation influencing Ca transportation and cycling in the riverine system constrained by stable Ca isotopic compositions and water chemistry

Germanium contents, Ge/Si ratios, and Sr isotopic composition in deep-sea cherts

Nineteen chert samples from a continuous core of the DSDP (Leg 17, Hole 167) were analysed for Ge; in addition we analysed five samples from other cores. The ages range between Late Jurassic, and Late Eocene. The concentration of Ge changes with age from 0.87 ppm in the oldest samples to 0.23 ppm in the youngest (equivalent to a Ge/Si decrease from 0.00000072 to 0.00000019). The decrease in Ge/Si is well correlated with the 87Sr/86Sr ratio in sea water of the relevant age. The interpretation of this trend may reflect: (a) different levels of Ge/Si in sea water as a result of a different ratio between hydrothermal and riverine input, (b) a diagenetic trend in siliceous sediments, (c) recording (by radiolaria) a transition between a radiolaria dominated ocean (with relatively high Ge/Si ratios in sea water) and diatom domination or (d) a combination of the above

(Table 2) Germanium contents, Ge/Si ratios, and Sr isotopic composition in cherts from DSDP Site 20-195

Nineteen chert samples from a continuous core of the DSDP (Leg 17, Hole 167) were analysed for Ge; in addition we analysed five samples from other cores. The ages range between Late Jurassic, and Late Eocene. The concentration of Ge changes with age from 0.87 ppm in the oldest samples to 0.23 ppm in the youngest (equivalent to a Ge/Si decrease from 0.00000072 to 0.00000019). The decrease in Ge/Si is well correlated with the 87Sr/86Sr ratio in sea water of the relevant age. The interpretation of this trend may reflect: (a) different levels of Ge/Si in sea water as a result of a different ratio between hydrothermal and riverine input, (b) a diagenetic trend in siliceous sediments, (c) recording (by radiolaria) a transition between a radiolaria dominated ocean (with relatively high Ge/Si ratios in sea water) and diatom domination or (d) a combination of the above