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Mineral Resources On-Line Spatial Data

Complete data dictionary for the National Geochronological Database

Tables and fields explained here are available only as part of the comprehensive download package geochron-csv.zip or in the full geodatabase geochron-gdb.zip

Table Description
main Sample locations and characteristics
FT Fission track dating results, observations, and parameters
K_Ar Potassium-Argon and Argon-Argon radiometric age results, observations, and parameters
Rb_Sr Rubidium-Strontium radiometric dating results, observations, and parameters
Sm_Nd Samarium-Neodymium radiometric dating results, observations, and parameters
U_Th_Pb Radiometric age estimates, observations, and parameters using techniques involving isotopes of uranium, thorium, and lead.
datadxny Data dictionary, explaining tables and fields

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