摘要
To evaluate the suitability of Penglai zircon as a reference material for zircon fission track thermochronology,we analyzed natural zircon megacrysts from Penglai,northern Hainan Island,southern China,using the fission track dating by LA-ICP-MS method.Through rigorous validation against the internationally recognized Fish Canyon Tuff zircon(FCT)standards,we demonstrate that our laboratory's measurement processes for fission track dating by the LA-ICP-MS method are reliable and practical.Three fission track ages of 4.02±0.23 Ma(1σ),4.11±0.26 Ma(1σ),and 4.16±0.27 Ma(1σ)were obtained from 52 fragments of three Penglai zircon megacrysts.The obtained fission track ages are homogeneous and highly reproducible,aligning with the(U-Th)/He ages.The chemical and textural analyses described by the CL and BSE imaging and EPMA results indicate that the three Penglai zircon megacrysts are nearly homogeneous.Penglai zircon megacrysts exhibit near homogeneity,weak broad zoning,unlimited quantity,rapid cooling,consistent fission track ages,and identical(U-Th)/He ages.These results confirm that Penglai zircon is suitable for use as a reference material for fission track thermochronology,provided that some caution is taken to verify fission track ages before selecting a Penglai zircon megacryst as a reference material.
基金
supported by the National Science and Technology Major Project(Grant No.2024ZD1001102)
the National Natural Science Foundation of China(Grant Nos.42241161,42072242)
the Fundamental Research Fund of Institute of Geomechanics,Chinese Academy of Geological Sciences(DZLXJK202303)。
