Water analyses typically result in numerous characteristic values. The bunch of parameters hamper temporal or spatial comparisons of different samples. In order to facilitate the evaluation and interpretation of hydrochemical data, hydrogeologists use various special diagrams. One of them is the Schoeller diagram, in which the concentrations of different chemical species are plotted on logarithmic scales. Entries of an analysis are connected and form a characteristic signature. In the Schoeller diagram, parallel or subparallel signatures indicate relatedness of waters. Here we present the idea of standardized Schoeller diagrams: different logarithmic axes are shifted with respect to each other so that the signatures of a selectable sample forms a straight line.

For this application, we have developed a plot tool that allows standardized Schoeller diagrams, such as the example above, to be plotted with minimal effort and only one command in the Matlab programming environment. All required files, including the program code of the plot command, a detailed tutorial, as well as sample commands for all plots of the tutorial can be found in this collection.