Advances of the(U-Th)/He thermochronology and its applications
The(U-Th)/He thermochronology is a dating method based on the accumulated 4He which was produced by the decay of parent isotopes including 238U,235U,232Th,and 147Sm.It has an irreplaceable advantage in quantitatively revealing the time-space-temperature characteristics of cooling and exhumation events occurred in the shallow level of crust,due to its low closure temperature and good sensitivity to near-surface geological processes.In this paper,we have briefly reviewed the principle of the(U-Th)/He thermochronology,and also reviewed the advantages and disadvantages of different analytical methods of the(U-Th)/He thermochronology.On this basis,we have summarized and discussed advances and shortcomings of(U-Th)/He thermochronology in terms of the mechanism of radiation damage on the diffusion behavior of 4He,annealing kinetics and the 4He diffusion model,and have prospected how to improve these shortcomings in the future.In addition,we have also reviewed the application examples and some limitations of the(U-Th)/He thermochronology method in the constraint of metallogenic epoch,exhumation history of the orogenic belt,and preservation evaluation of ore deposits.