Borehole samples were obtained from the glacial, lacustrine and fluviatile sands and clays which overlie the Permo-Triassic sandstone aquifer in the Vale of York. Mineralogical and chemical analyses were undertaken for 26 samples from which pore water was also extracted and analysed. Ion concentrations in pore water were found to change as a function of depth and permeability. Most of the ions present in pore water are thought to be derived from the drift and the source minerals have been identified. The superficial deposits are thought to have an important influence on the chemistry of ground water in the underlying Permo-Triassic sandstones.
Comparison with ground water from similar aquifers, but drift free, indicates that in these cases the sandstone exerts an important influence on ground water chemistry.