General geology, hydrogeology and major Ion concentration in and around Kg. Jelawat, Gunong, Bachok

The study focuses on the general geology, hydrogeology and major ion concentration in and around of Gunong, Bachok, Kelantan. The study area lays between from 5°56'0" N to 6°2'0" N latitudes and from 102°21'0" E to 102°26'30" E longitudes. The study area is a part of the unconsolidated sediment, representing the flat Kelantan alluvial plain is of Quaternary age and overlies granitic bedrock. This granite outcrop can be found in few locations in the form of intrusion. Data was obtained through geological mapping and site sampling from available outcrops. Lithology found in this study area is undifferentiated acid intrusive, clay, silt, sand and gravel as well as sand (mainly marine). From this study area, one rock samples was collected, and petrography analysis was carried out. A new updated geological map was presented at the end of the research. The rock sample was identified as syeno-granite or alkali feldspar granite. As the groundwater is one of the largest sources of freshwater in the study area, simultaneous study was performed based on the major ion concentration in domestic groundwater well, water level of domestic well and behaviour of groundwater movement in the study area. Groundwater samples were taken from 12 locations within the study area. The sampling site was chosen to the availability of well at the location. Groundwater samples were collected in one 1.5 litres acid washed well-rinsed polyethene bottles and analysed for physical and chemical parameters. In-situ parameters were measured using the YSI portable multi parameter such as temperature, electrical conductivity, dissolved oxygen (DO), pH and TDS. The analysed chemical parameters include major cations like sodium (Na⁺ ), potassium (K⁺), calcium (Ca²⁺) magnesium (Mg²⁺) and anions such as bicarbonate (HCO⁻₃), chloride (Cl⁻), nitrate (NO⁻₃), sulphate (S0²⁻₄), and fluoride (F⁻). Generally, the well water in the study area is safe for drinking when compared with the WHO and MOH standards except for potassium (K⁺) which exceeds the standard permissible limit of WHO and MOH.