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The hafnium isotopic analysis using laser ablation has been widely conducted on Hf-rich minerals(zircon/baddeleyite/ calzirtite/eudialyte), however, little work has been reported on Hf-poor(<100 ppm) minerals. This work presents a detailed procedure of in situ hafnium isotopic analysis from rutile using laser ablation multiple collector inductively coupled plasma mass spectrometry(LA-MC-ICP-MS). The rutile U-Pb dating reference material JDX shows homogeneous hafnium isotopic ratios, with 176Hf/177Hf=0.281795±0.000015(2SD, n=33) and 176Lu/177Hf=0.000018±0.000004(2SD, n=17) that suggest the possibility of using JDX as a new reference material hafnium isotopic measurement. We also measure hafnium isotopic compositions of other rutile U-Pb dating reference material(R10, Sugluk-4 and PCA-S207) and the 176Hf/177 Hf values are similar to previously reported results, which confirms that we can acquire accurate and precise hafnium isotopic compositions using our developed analytical protocol. We analyzed hafnium isotopic compositions and U-Pb ages of rutile in high-temperature and ultrahigh-temperature granulites from various terrains of the Khondalite Belt from the North China Craton, combined with zircon results in the same area, suggesting that the metamorphic evolution history of the granulite is much more complicated than previously thought.
The hafnium isotopic analysis using laser ablation has been widely conducted on Hf-rich minerals (zircon / baddeleyite / calzirtite / eudialyte), however, little work has been reported on Hf-poor (<100 ppm) of in situ hafnium isotopic analysis from rutile using laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS). The rutile U-Pb dating reference material JDX shows homogeneous hafnium isotopic ratios with 176Hf / 177Hf = 0.281795 ± This suggests the possibility of using JDX as a new reference material hafnium isotopic measurement. We also measure hafnium isotopic compositions of other rutile U- Pb dating reference material (R10, Sugluk-4 and PCA-S207) and the 176 Hf / 177 Hf values are similar to previously reported results, which confirms that we can acquire accurate and precise hafnium isotopic compositions using our developed analytical protocol. Weathered hafnium isotopic compositions and U-Pb ages of rutile in high-temperature and ultrahigh-temperature granulites from various terrains of the Khondalite Belt from the North China Craton, combined with zircon results in the same area, suggesting that the metamorphic evolution history of the granulite is much more complicated than previously thought.