Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Bedrock Geology
This data set represents the area of bedrock geology types in square meters compiled for every 
catchment of NHDPlus for the conterminous United States. The source data set is the "Geology 
of the Conterminous United States at 1:2,500,000 Scale--A Digital Representation of the 1974 
P.B. King and H.M. Beikman Map" …