Home / Standards / GB/T 46420-2025 GB/T 46420-2025 Active (U-Th)/He isotope determination and age calculation method of apatite and zircon 磷灰石和锆石铀、钍、氦同位素测定与年龄计算方法 Standard Type GBT ICS 75.010 CCS E11 Status 现行 Issue Date 2025-10-05 Implementation 2026-05-01 Responsible Dept 国家标准委 Drafting Unit N/A