In situ apatite U-Pb dating for the ophiolite-hosted Nianzha orogenic gold deposit, Southern Tibet

•Nianzha is an ophiolite-hosted large orogenic type gold deposit in Southern Tibet.•Two different types (magmatic and hydrothermal) of apatite were identified in the Nianzha.•U-Pb dating of hydrothermal apatite revealed an Eocene gold mineralization event (ca. 44 Ma) in Nianzha.•Hydrothermal apatite U-Pb chronometer is effective in constraining the age of orogenic-type gold mineralization.