USGS GEOCHRON: QUALITY ASSURANCE AND QUALITY CONTROL OF COMPILING LEGACY GEOCHRONOLOGY DATA

The USGS Geochron database is a new compilation of USGS-funded and coauthored geochronological and thermochronological dates and data. These data are integral components of geologic mapping utilized by researchers, stakeholders, and the science-interested public to study the Earth’s lithospheric and surficial processes and to manage resources and natural hazards.

Previous USGS efforts to compile a geochronological database began in the 1970s with the Radiometric Age Data Bank (RADB) which was converted to the National Geochronological Database (NGDB) in the 1990s after which compilation stopped for that database. We have converted the NGDB to a centralized server-hosted PostgreSQL relational database and have started compiling the 30+ year backlog of published USGS geochronological and thermochronological data. A series of automated and manual quality control and quality assurance procedures minimize errors during compilation and data export to public data releases. We have created a standardized workflow for the compilation of data from machine-readable data tables and non-machine-readable scanned documents and have implemented procedures for efficiently mining associated publications to capture essential sample and analytical method metadata.

The data span analytical techniques from Quaternary methods, such as optically stimulated luminescence, to long-lived isotopic systems, such as the U-Th-Pb, Sm-Nd, and ⁴⁰Ar/³⁹Ar methods, reflecting the diversity of USGS analytical labs and projects. We anticipate adding additional schema to the database to cover recent analytical techniques that were not included in previous compilations. The USGS Geochron database has been published as a ScienceBase-hosted data release of flattened CSV files of the entire database and will be updated regularly (doi.org/10.5066/P9RZNPIF). The USGS Geochron database is a part of the USGS’s Geologic Framework of the Intermountain West mapping effort in collaboration with the National Geologic Map Database (NGMDB). This project is consistent with the USGS mission to provide reliable scientific information and will make USGS-generated data available in a readily accessible and searchable way that supports the FAIR (Findable, Accessible, Interoperable, and Repeatable) data principles.