For the samples labeled (1) concentrations after the first leach to remove the carbonate fraction (after Barrett et al., 1987, doi:10.1016/0016-7037(87)90278-X); labeled (2) - after the second acid-reducible leach to remove the amorphous to poorly crystallized oxyhydroxide phases. All samples contain a small component of fine-grained insoluble clastic material, generally less than several percent of the carbonate-free fraction. CaCO3 concentration was determined by proportion of sediment removed in the first leach.