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USGS2020

U-Pb geochronology of igneous and detrital zircon samples from the Tok River area, eastern Alaska Range, and Talkeetna Mountains, Alaska

This Alaska Division of Geological & Geophysical Surveys (DGGS) Raw Data File presents U-Pb zircon geochronology results from selected igneous, meta-igneous, and metasedimentary rocks collected during the Tok River and Wrangellia geologic mapping projects in the eastern Alaska Range and the northwestern Talkeetna Mountains, Alaska. The purpose of these analyses is to better constrain the age of select geologic units encountered during the mapping projects.

Alaska↗

USGS2019

U-Pb and Lu-Hf isotope, age, and trace-element data from zircons at four sites in the western Alaska Range and Talkeetna Mountains, Alaska

This Division of Geological & Geophysical Surveys (DGGS) Raw Data File presents U-Pb geochronology and Lu-Hf isotopic compositions, age-dating results, and additional trace-elemental composition of zircons from four granitoids sampled during investigations by DGGS geologists in the western Alaska Range and the Talkeetna Mountains. The purpose of the Lu-Hf and U-Pb isotopic study was to better understand the Jurassic through early Tertiary magmatic and tectonic evolution of the Alaska Range and the significance of that magmatism for the formation of metallic mineral deposits. The U-Pb isotopic data also serve to further refine the crystallization age of plutons, which were previously ambiguous in 40Ar/39Ar geochronology studies.

Alaska↗