Gibb′s ideas as both plots of total dissolved solids (TDS) versus (Na+K)/(Na+K+Ca) and Cl/(Cl+HCO3) weight ratios where the concentration of ions is in meq/l. These diagrams are widely used in order to have an explanation of the general chemistry of water.
so, the article in link below explains this phenomenon.
Wilcox and Gibbs graphical diagrams are one of the oldest way of classification of groundwater. Good published literature available For preparation and detailed study.
Gibbs diagrams are an effective tool to identify the major natural geochemical processes (such as precipitation, rock weathering , and evaporation) controlling the hydrogeochemical characteristics of groundwater in the aquifer. Gibbs diagram is obtained by plotting TDS against Na+/(Na++ Ca2+) and Cl-/(Cl- + HCO3- ).
You can use AquaChem software or Diagrammes Version 6.61
2-Wilcox diagram
Groundwater suitability for irrigation mainly depends on the concentration of total salinity and sodium related to other ions. Wilcox plot of Na % against EC to assess the irrigation water suitability. EC :electrical conductivity, a measure of the total salinity, is usually used to classify irrigation water quality. Sodium percentage (Na%) is another important parameter to indicate the suitability of water for irrigation.
Sir both Wilcox and Gibbs diagrams are plotted in an excel sheet. The Wilcox diagram indicates the suitability of irrigation for different ranges vales for % Na and Gibbs plotted was indicate that major ions controlled for rock water interaction and evaporation zones.
Dear Verma... please Download Diagrames softwere and which is very helpful to prepare Wllcox, Piper, Scholar, USSl and all other Groundwater quality related diagrams will prepare in this software.... otherwise Aqqa software also good for Piper and Durov Diagrams preparation... Pls use this below link to download the software..