Analysis and Discussion of Strontium Isotopes in Uranous Sandstones From Yili Basin With Sequential Extraction Technique" />
uranium-bearing sandstones；87Sr/86Sr；sequential extraction technique；mineral composition
Analysis and Discussion of Strontium Isotopes in Uranous Sandstones From Yili Basin With Sequential Extraction Technique
In this paper，six uranium-bearing sandstone samples from Yili basin were tested with sequential extraction technique to study the distribution of Sr isotope ratios. Sr was extracted with deionized water，0.5 mol/L acetate，0.5 mol/L hydrochloric acid，concentrated nitric acid and hydrofluoric acid respectively and 87Sr/86Sr were measured by thermal ionization mass spectrometry（TIMS）. The results showed that 87Sr/86Sr was not consistent in different extraction states. The 87Sr/86Sr in the extraction state of concentrated nitric acid and hydrofluoric acid were much higher than the 87Sr/86Sr in the extraction state of hydrochloric acid，acetic acid and deionized water. Acetic acid extraction stage mainly dissolved carbonate minerals. The 87Sr/86Sr in the extraction state of acetic acid ranged from 0.709 89 to 0.711 50，higher than that of sea water in same period（0.707 7 to 0.708 3），but similar to the 87Sr / 86Sr of lake water（0.711 9）. It is showed that the deposition process was affected by the terrestrial fluid，which is consistent with the previous studies reporting that sandstone in Yili basin was sedimented in the fan delta caused by the alluvial fan quickly into the lake.