Thermal study of the Duolong ore district in Tibet: implications for the uplift history of the Qiangtang terrane

This paper presents new apatite fission track (AFT) and apatite (U-Th)/He (AHe) data from the Duolong ore district. The corresponding AFT and AHe ages provide insights into the uplift and exhumation history of the Duolong ore district, revealing rapid exhumation with an erosional exhumation rate of 0.067 km/Ma between 65 and 35 Ma, and slow exhumation with an erosional exhumation rate of 0.023 km/Ma since 35 Ma. The new data in this study, along with previous low-temperature thermochronology data, show that samples with ages from 130 to 83 Ma are distributed close to Shuanghu in the central Qiangtang, samples with ages from 65 to 45 Ma are distributed evenly across the whole Qiangtang terrane, and several samples with ages from 20 to 7 Ma are distributed at the edge of the Qiangtang terrane. The Qiangtang terrane experienced heterogeneous surface uplift. The central Qiangtang was initially uplifted during the Early Cretaceous, and the weathered paleosoil dated between 120 and 110 Ma in the Duolong ore district is consistent with the exhumation during this period. Large-scale uplift and exhumation of the Qiangtang terrane between the Palaeocene and Eocene is consistent with the rapid exhumation of the Duolong ore district between 65 and 35 Ma; finally, the uplift and exhumation at the edge of the Qiangtang terrane since the Eocene caused the Duolong ore district to be uplifted to its present elevation.

Automated summary

This study presents new apatite fission track (AFT) and apatite (U-Th)/He (AHe) data to reveal the uplift and exhumation history of the Duolong ore district. The ages show rapid exhumation between 65 and 35 Ma, followed by slower exhumation since 35 Ma. Heterogeneous surface uplift of the Qiangtang terrane is observed, with Central Qiangtang experiencing uplift in the Early Cretaceous and the Duolong ore district showing evidence of exhumation during that period. Large-scale uplift and exhumation from the Palaeocene to Eocene correlates with the rapid exhumation in the Duolong ore district between 65 and 35 Ma, and uplift and exhumation at the edge of the Qiangtang terrane since the Eocene resulted in the present elevation of the Duolong ore district.