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Uranium-Lead Ages, Hafnium Isotope Ratios, and Trace Element Concentrations by Laser-Ablation Split Stream (LASS) Analysis of Igneous Zircons from the Darby Mountains Area, Seward Peninsula, Alaska

Data Download [282KB] | Metadata | AK Science Portal | Date Range: 2023 - 2023


This data set contains uranium–lead (U-Pb) isotopic data and ages, hafnium (Hf) isotope data, and trace element concentrations of zircon from igneous rocks collected from the Darby Mountains area of the Seward Peninsula, Alaska. The sample suite was collected as part of geological mapping and supporting geochemical and geochronological analysis conducted in 2017. The data tables accompanying this data release report the isotopic composition of U and thorium (Th) measured in each grain, ratios of 207Pb and 206Pb and 235U and 238U, and the age of each grain, plus trace element abundances from the same ablated aliquot, including phosphorus (P), vanadium (V), strontium (Sr), high field strength elements (HFSE), and rare earth elements (REE). Reported Hf (and lutetium, Lu) isotope data includes 176Hf/177Hf, 176Lu/177Hf, and 178Hf/177Hf ratios, calculated epsilon Hf values, and age-corrected isotope ratios and epsilon values.

Author(s): Drewes-Todd, E. K.; Todd, E.; Kylander-Clark, A. R. C.; Pongratz, A. L.

Suggested Citation:
Drewes-Todd, E. K., Todd, E., Kylander-Clark, A. R. C. and Pongratz, A. L., 2023, Uranium-Lead ages, Hafnium isotope ratios, and trace element concentrations by Laser-Ablation Split Stream (LASS) analysis of igneous zircons from the Darby Mountains area, Seward Peninsula, Alaska: U.S. Geological Survey data release, https://doi.org/10.5066/P9JKR2J6.


DataID: 545 | doi:10.5066/P9JKR2J6 | Date Posted Online: 2023-01-23 | Last Updated:

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