New U-Pb Geochronology and Geochemistry of Paleozoic Metaigneous Rocks from Western Yukon and Eastern Alaska ...

• Main Authors: Cynthia Dusel-Bacon, James K. Mortensen
• Format: Dataset
• Language: unknown
• Published: U.S. Geological Survey 2023
• Subjects: geology; geochemistry; isotopic analysis; isotopes; trace elements; geochronology; radiometric dating; age determinations; uranium-lead analysis; igneous rocks; metamorphic rocks; uranium-thorium analysis; major elements; minor elements; radioactive elements; whole-rock geochemistry; Alaska; Yukon; Big Delta; Eagle; Fairbanks; Tanacross
• Online Access: https://dx.doi.org/10.5066/p93zwga1; https://www.sciencebase.gov/catalog/item/64d23dfcd34ef477cf3c4550

This data release contains three tables of U-Pb zircon isotopic data generated from analyses of 40 metaplutonic and metavolcanic rocks from the Yukon-Tanana Upland of western Yukon and east-central Alaska and one sample from southern Yukon. One of the tables also reports U-Pb data for two titanite analyses for one of the samples. U-Pb zircon ages from analyzed samples range from 363.5 plus/minus 3.8 to 253.1 plus/minus 0.7 Ma and were collected from parautochthonous North America and the allochthonous Yukon-Tanana terrane. U-Pb zircon data include 216 individual analyses by ID-TIMS and 35 individual analyses of two samples by LA-ICP-MS. ID-TIMS analyses of titanite give concordant 206Pb-238U ages of 333 and 338 Ma. Two U-Pb tables report the isotopic composition of uranium (U) and thorium (Pb) measured in each grain, ratios of isotopes of lead and uranium isotopes, and the age of each grain. A third table reports interpreted U-Pb ages, sample locations, tectonic assemblage or unit, lithology, analysis ...