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Cosmogenic Al-26/Be-10 Isochron Burial Age Data for Pleistocene Alluvial Deposits in the Salida, Colorado Area

July 21, 2025

This data release contains three comma separated value (.csv) tables describing data from alluvial cobbles collected from a Pleistocene alluvial deposit on the noerth side of Poncha Pass, near Salida, Colorado. Tables "DryUnion_Burial_Isochron_Aluminum26_Cyr.csv" and "DryUnion_Burial_Isochron_Beryllium10_Cyr.csv" contain aluminum-26 and beryllium-10 data, respectively, for samples collected in Poncha Pass, Colorado on July 15, 2015. Table "DryUnion_LocationAndIsochronBurialAge_Cyr.csv" contains location, elevation, site-specific nuclide production ratios, and interpreted isochron burial age results. Physical and chemical isolation of clean quartz was carried out in the Menlo Park Cosmogenic Nuclide Lab; chemical isolation of aluminum and beryllium, and isotope analysis by accelerator mass spectrometry, were completed at the Purdue Rare Isotope Measurement (PRIME) Lab at Purdue University, West Lafayette, Indiana. Users of this dataset should note that "Dry Union" was used as a geographic designation at the time of sample collection. Subsequent geologic mapping has demonstrated that both the "Upper Dry Union" and "Lower Dry Union" sets of samples were collected from an alluvial apron, unit Qoa of Minor and others (2019), that laps unconformably on the Dry Union Formation (as defined by Minor and others, 2019 and references therein). Our isochron burial age result demonstrates that unit Qoa at this location is 0.30 +/- 0.05 Ma.

Publication Year 2025
Title Cosmogenic Al-26/Be-10 Isochron Burial Age Data for Pleistocene Alluvial Deposits in the Salida, Colorado Area
DOI 10.5066/P13GFOVU
Authors Andrew J Cyr, William E Odom, Chester A. Ruleman, Scott A Minor
Product Type Data Release
Record Source USGS Asset Identifier Service (AIS)
USGS Organization Geology, Minerals, Energy, and Geophysics Science Center
Rights This work is marked with CC0 1.0 Universal
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