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Application of Statistical Methods for Delineating Water Quality in the Dakota Aquifer

by Margaret A. Townsend and Xiaodong Jian
Kansas Geological Survey, The University of Kansas
Lawrence, Kansas
Kansas Geological Survey Open-file Report 93-1B


Statistical analysis is commonly used to evaluate large data sets for trend or groupings and to indicate areas of future study. For this study, various statistical tests were performed to determine the accuracy of the methods in classifying data in comparison to the water-typing method of Piper (1944). The statistical tests also were evaluated in terms of usable results for persons who are not familiar with evaluating geochemical data for trends.

The personal computer package Statistical Package for the Social Sciences (SPSS), version 4.0 (1990) was used to evaluate water chemistry data from the Dakota study data base. As of 1988, the data base contained more than 900 complete and partial analyses. Of these, samples with complete analyses (major cations and anions: calcium, magnesium, sodium, chloride, sulfate, and bicarbonate) from 250 discrete locations were selected for evaluation. A subsample was used for ease in comparison of the several statistical methods used. At a future time, these methods will be tried on the entire Dakota water chemistry database.

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Kansas Geological Survey, Dakota Aquifer Program
Original report available from the Kansas Geological Survey.
Electronic version placed online Nov. 1998
Scientific comments to P. Allen Macfarlane
Web comments to webadmin@kgs.ku.edu