Instrumental mass fractionation (IMF) associated with Secondary Ion Mass Spectrometry (SIMS) measurements of oxygen isotope compositions in silicate glasses was studied using a set of 27 synthesized glasses spanning a compositionally broad range of six major oxides: SiO₂, TiO₂, Al₂O₃, total FeO (FeO_t), MgO and CaO. The impact of chemical composition on the IMF values was investigated using a Cameca 1280-HR during a single SIMS analytical session operated under constant instrumental conditions. The data measured were compared with the δ¹⁸O values obtained by laser fluorination gas source mass-spectrometry (LF). The offset between the δ¹⁸O(LF) and δ¹⁸O(SIMS) was found to reach up to 5‰. Our data document that SIMS oxygen isotope matrix effects in silicate glasses strongly depend on the chemical composition of silicate glasses, here the cation‑oxygen bond strength was found to have a strong influence on the IMF value. We tested a variety of models based on single oxide contents and various composition-dependent parameters, but none were fully satisfactory for predicting IMF. Neither mean atomic mass nor NBO/T (the ratio of non-bridging oxygens per tetrahedrally coordinated cation) show a strong correlation with the IMF values (R² of 0.45 and 0.46, respectively). Among the single oxides, only the model based on the SiO₂ content is useful for prediction of the IMF in silicate glasses, but this model has a large standard error (1σ = ± 0.90‰) and was also found to break down for glasses with high Na and K contents. We propose an empirical model based on the correlation of six major element oxides that shows a strong correlation with IMF (R² = 0.98, 1σ = ± 0.40‰). This model describes the experimental data with uncertainties that are roughly a factor of two better than the correction methods proposed in earlier studies. We also investigated using the correlation between IMF and isotope I-¹⁸O index, which describes the correlation between atomic bond strength and relative oxygen isotope enrichment in silicate substances (R² = 0.87). Although our efforts provide refinements to the SIMS determination of δ¹⁸O in natural silicate glasses, truly accurate IMF corrections will need further refinements related to the impact of alkali elements.

使用一组27种合成玻璃，研究了组成范围广泛的六种主要氧化物：SiO ₂，TiO ₂，Al ₂，研究了与二次离子质谱（SIMS）测量相关的硅酸盐玻璃中氧同位素组成的仪器质量分数（IMF）O ₃，总FeO（FeO _t），MgO和CaO。在恒定仪器条件下运行的单个SIMS分析会话中，使用Cameca 1280-HR研究了化学成分对IMF值的影响。测得的数据与δ进行比较^18个通过激光氟化气体源质谱（LF）所得的O值。所述δ之间的偏移¹⁸ O（LF）和δ发现¹⁸ O（SIMS）达到5‰。我们的数据文件表明SIMS氧同位素基质在硅酸盐玻璃中的作用在很大程度上取决于硅酸盐玻璃的化学组成，此处发现阳离子-氧键强度对IMF值有很大影响。我们基于单一氧化物含量和各种成分相关参数测试了多种模型，但没有一个模型能够完全令人满意地预测IMF。平均原子质量和NBO / T（每个四面体配位阳离子的非桥接氧之比）均与IMF值均无强相关性（R ²分别为0.45和0.46）。在单一氧化物中，只有基于SiO ₂的模型含量可用于预测硅酸盐玻璃中的IMF，但该模型的标准误较大（1σ=±0.90‰），并且对于高Na和K含量的玻璃也可分解。我们基于六种主要元素氧化物的相关性提出了一个经验模型，该模型显示出与IMF的强相关性（R ²  = 0.98，1σ =±0.40‰）。该模型描述的实验数据具有不确定性，其不确定性要比早期研究中提出的校正方法好大约两倍。我们还使用IMF和同位素I- ¹⁸ O指数之间的相关性进行了研究，该相关性描述了硅酸盐物质（R ² = 0.87）。虽然我们的努力提供了改进，以δ的SIMS确定¹⁸天然硅酸盐玻璃O，真正准确的IMF修正需要与碱金属元素的影响的进一步改进。