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U-Pb ages of detrital zircons in Paleogene strata of the Gulf Coast

August 26, 2021

This data release contains 60 detrital zircon age spectra, based on U and Pb isotope ratio measurements for 9399 single grains. The samples are from Paleogene strata of the U.S. Gulf Coast. Of the 9399 single grain measurements, we recommend that 8640 yield ages that are suitable for construction of detrital zircon age spectra. Comments tagged to individual grains explain the reasoning for exclusion of a single grain measurement from age spectra, mostly including high discordance and/or uncertainty. The samples were collected along the strike of the U.S. Gulf Coast basin between western Alabama (the eastern U.S. Gulf Coast) and the Rio Grande river (the southwestern boundary of the U.S. Gulf Coast). The highest sample densities are in Middle (34 samples) and Upper (13 samples) Eocene strata. The dataset also includes 1 sample from the Midway Group, 7 samples from the Wilcox Group, 2 samples from the Vicksburg Group, 1 sample from the Frio or Vicksburg Group, and 2 samples from the Frio Group. Sample latitudes and longitudes are provided in a table, along with brief summaries of sample locations. All elemental concentrations and isotope ratios were measured with a laser ablation inductively coupled plasma mass spectrometer at the University of California at Santa Barbara. Isotope ratios were input into the age equations using the IsoPlot 4.1 software package, including decay constants for uranium-238 of 1.55125x10^-10 and for uranium-235 of 9.8485x10^-10.