Analytical results for Pb-concentrations and isotopic ratios from about 150 samples of soil A horizon and about 145 samples of soil C horizon collected along a 4000-km east-west transect across the USA.

Sample locations, location descriptions, lithology, mineralogy, and geochronological relationships of drill holes that penetrated the buried Precambrian basement in this area. Detailed well log and cutting descriptions are included if available. Data are provided in Microsoft Access and tab-delimited text formats.