Over 20 years ago the data in these listings were coded into the Saskatchewan Geological Survey’s ‘Geochemical Data File’, designed in the 1970s (Dunn, 1978b, 1979), and developed by SaskComp (the computer programming department of the Saskatchewan government at that time). The only database listed in the present report that was not in the Geochemical Data File was GSC Open File #779, jointly produced by the SGS and GSC (Coker and Dunn, 1981, 1983) and containing data from detailed surveys of the IAEA/NEA Athabasca Test Area (adjacent to Wollaston Lake). The old Geochemical Data File was state-of-the-art at the time, and data have been available for public scrutiny since inception in 1977. Demonstrations of the File were given at the SGS Open House meetings in 1977 and 1978.
The explosive development of personal computers during the past 20 years has made the original Geochemical Data File something of a dinosaur, and the data have been difficult to access and manipulate. The present data file is a compilation that has resulted from detailed evaluation, streamlining, editing and breakdown of the data into simplified Excel files that can easily be manipulated by anyone with a modest knowledge of computers. These data are of historic value and their re-evaluation could assist in current uranium exploration programmes. Of particular value is their use in environmental studies, since they represent a 1970s snapshot of the chemistry of the northern Saskatchewan environment prior to mine developments. At the start of sample collection in 1975 Key Lake had not been drained and the only mine site was the pit at Rabbit Lake.
This compilation has divided the data into 9 tables, each presented as a shape file. There are 6 shape files of lake sediment data (1LS - 6LS) and 3 shape files of lake water data (4LW - 6LW). Lake water samples were from the same sites as the lake sediments listed in files 4LS - 6LS, hence they have been given the same numeric designation.
The data are mostly compatible among the Tables. However, although analytical methods and quality control protocols were similar, they were sufficiently different to warrant treating the data as separate listings. For any regional plotting of data extracted from all Tables these differences should be considered when interpreting distribution patterns.
Of particular relevance is that all sediment samples were analyzed for U by neutron activation, with the exception of 158 samples (Table 2LS) where determinations were by fluorometry. These data sets should be fully compatible, because the two techniques provide similar values. Comparison of U data from sediment samples collected and analyzed over four years, then reanalyzed as one batch has shown excellent precision and accuracy (Coker and Dunn, 1981). All U in water determinations were by fluorometry, and all F- by selective ion electrode. Loss on ignition (LOI) data were determined by ignition at 500o C for 4 hours.
Samples were collected into Nalgene bottles from a few cm below the lake surface. They were not filtered prior to analysis by standard laboratory methods.