Use of various statistical techniques to assess the vertical and lateral change in the groundwater chemistry of Quaternary aquifer in an irrigated highly populated area

Abstract

A large Hydrogeochemical data were obtained from the central Nile delta aquifer system where 167 groundwater samples were gathered from three depth zones and analyzed for majors and minors. Different statistical techniques were applied to the analyzed geochemical data. The target of the current investigation is to find the principle factors and processes controlling the variation in the hydrogeochemistry in the three groundwater zones. The physicochemical analysis revealed that concentrations of majors (K, Na, Ca, Mg, HCO3, Cl and SO4) with some traces as NO3, Si, NH4 and Fe decrease from the shallow zone to reach its lowest values in the deep zone because of the surface hydrologic and anthropogenic factors affect the shallow groundwater. The studied groundwater classified into five series, every series has its own hydrochemical type. It is revealed that the shallow groundwater was affected by surface hydrochemical process, soil salinity and water–rock interaction as main sources of groundwater salinity. There are two origins of the deep groundwater, one is fresh flowing from south to north and the other is influenced by the intruded seawater in the northern part of the investigated region. The groundwater of the intermediate zone is a mix between the shallow groundwater and the deep groundwater.