Allison Dombrowski (Former Employee)
Science and Products
The National Geologic Map Database (NGMDB)
The National Geologic Map Database (NGMDB) is a distributed archive of geoscience information for the Nation. It was mandated by the Geologic Mapping Act of 1992 and is cooperatively built and maintained by the USGS and State Geological Surveys. We welcome you to explore the archive, view the maps, and help us to improve this resource.
USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 2.0, September 2023)
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, and luminescence. This data set incorporates data prev
Science and Products
- Science
The National Geologic Map Database (NGMDB)
The National Geologic Map Database (NGMDB) is a distributed archive of geoscience information for the Nation. It was mandated by the Geologic Mapping Act of 1992 and is cooperatively built and maintained by the USGS and State Geological Surveys. We welcome you to explore the archive, view the maps, and help us to improve this resource. - Data
USGS Geochron: A Database of Geochronological and Thermochronological Dates and Data (ver. 2.0, September 2023)
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, and luminescence. This data set incorporates data prev