Records and Data Produced at the USGS Argon Extraction Laboratory in Anchorage, Alaska

This dataset is a collection of analytical data of potassium-argon (K/Ar) radiometric age analyses. K/Ar dating used conventional argon measurements by isotope dilution with mass spectrometry, and potassium was determined by flame photometry using a lithium metaborate fusion.

The analyses were performed over a period of nearly 20 years, from the mid 1970's to 1994. Most of the argon extractions presented here were performed at the argon extraction laboratory at U.S. Geological Survey (USGS) in Anchorage, Alaska, which was located in Gould Hall of Alaska Pacific University. Prior to 1982, the argon extractions were done at one of the argon laboratories in Isotope Geology in USGS Menlo Park, California.

The argon laboratory in Anchorage was not equipped with a mass spectrometer, and the argon extractions were analyzed on mass spectrometers in USGS Isotope Laboratory in Menlo Park or the Geochronology Laboratory at University of Alaska Fairbanks.

Most of the samples in this dataset were collected in Alaska to support various geologic studies; however, there are some samples from Bolivia and Turkey included, as these samples were processed and analyzed in the USGS Anchorage laboratory.