This data release contains water chemistry data used to create a total dissolved solids (TDS) map of the Keg River / Winnipegosis hydrostratigraphic unit (HSU). The data were acquired from publicly available formation water chemistry data from oil and gas well drillstem tests (DST) and production fluids, as well as industry monitoring wells accessed through environmental impact assessments reports.
Data have been processed, relevant records selected, and outliers removed to compile this dataset.
Process steps for selection of formation water analyses from oil and gas wells:
1. Records containing depth of tested interval information were selected;
2. The tested interval length was constrained to less than or equal to 50 m;
3. The acceptable charge balance error was constrained to ±10%;
4. Samples labelled as “incomplete analysis" were excluded;
5. Records were allocated to the Keg River / Winnipegosis HSU based on the depth information for the tested interval;
6. Records with tested intervals straddling the top or bottom of the Keg River / Winnipegosis HSU were excluded, unless they were from wells in data-poor areas and it was verified that less than 30% of the tested interval extended into the formation directly above or below the HSU, but not into any other formation;
7. In case of collocated data, the most representative sample was selected, or averaging of TDS values was done;
8. The concentration of total dissolved solids (TDS) was determined either by summing the concentration of major constituents (if available), or by using the TDS values as reported in the source dataset (if major constituents were not available)
The remaining formation water analyses were subjected to additional screening to identify potential contamination of the formation water by drilling fluids such as acid water, corrosion inhibitors, mud filtrates, and alcohols.
Process steps for selection of formation water analyses from compiled sources:
1. Any records where the sampled interval was identified as the Keg River / Winnipegosis HSU were included in the initial dataset.
2. Filtering was done based on the information provided in the reports.
The final dataset includes only those records that were used in the production of the final TDS surface.
Details about the screening process can be found in the following reference: Jensen, G.K.S., Rostron, B., Palombi, D., and Melnik, A. (2013): Saskatchewan Phanerozoic Fluids and Petroleum Systems project: hydrogeological mapping framework; in Summary of investigations 2013, Volume 1, Saskatchewan Geological Survey, Sask. Ministry of the Economy, Misc. Rep. 2013-4.1, Paper A5, 10 p. URL http://publications.gov.sk.ca/details.cfm?p=80100 [October 2014].