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Screengrab of USGS Geochron Database Explorer showing an example informational window. Clicking a point in the map brings up information for 40Ar/39Ar, Fission Track, K-Ar, Lu-Hf, Rb-Sr, Sm-Nd, U-Th-Pb In-situ, and U-Th-Pb TIMS data.
Public Domain.
