USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 4.0, May 2025)

USGS Geochron is a database of geochronological and thermochronological dates and data. The data set contains published ages, dates, analytical information, sample metadata including location, and source citations. The following analytical techniques are represented in the data set: 40Ar/39Ar, K-Ar, U-Th-Pb, Sm-Nd, Rb-Sr, Lu-Hf, fission track, luminescence, U-series, (U-Th)/He, Re-Os, 10Be and 26Al cosmogenic, and radiocarbon. This data set incorporates data previously hosted in the National Geochronological Database (Sloan and others, 2003), as well as data from published journal articles and ScienceBase data releases. These data are primarily from the United States, but data from other parts of the world are also included.

First posted: January 2023 (version 1.0 - available from authors)
Revised: September 2023 (version 2.0 - available from authors)
Revised: May 2024 (version 3.0 - available from authors)
Revised: June 2025 (version 4.0)