An integration of hydrochemical data and stable isotopes in groundwater evaluation in Ngboejogu, Southern Benue Trough, Nigeria

An essential component of groundwater research is the evaluation of isotope and groundwater qualities. Twenty (20) samples were collected for this investigation from groundwater source (boreholes and hand-dug wells). Physicochemical parameters analyzed followed the America Public Health Association (APHA) standard and findings reveled that EC, TDS, and pH were 370 to 891 μS/cm, 184 to 447 mg/L, and 6.40 to 7.51, respectively. The hydrochemical facies that dominated were Na⁺–HCO₃⁻ and Ca²⁺–Mg²⁺–HCO₃⁻, according to the Chadha classification. Every groundwater sample from Gibb's plot fell into the zone of rock domination. According to Soltan's classification, 45% samples were classed as deep meteoric type and 55% as shallow meteoric type. Na⁺/(Ca²⁺ + Mg²⁺) vs Cl⁻/SO₄²⁻ suggested that 75% of sampled groundwater as permanently hard water, while Ca²⁺/(HCO₃⁻ + SO₄²⁻) vs Na⁺/Cl⁻ suggested that 45 and 40% of the samples were within the natural and cation exchange state, respectively. The trend line on Na/Cl against EC plot sloped as EC rises, signifying that evaporation is not the primary factor. Significantly more samples were found to be below the equiline, Na/Cl vs EC both showed greater than one, specifying that silicate and carbonate weathering had an impact on groundwater. According to ion exchange result, carbonate and silicate weathering influenced sampled groundwater. Results of Na%, SSP, SAR, PS, and PI reveled that sampled groundwater were appropriate for irrigation use. Stable isotope tests revealed significant fluctuations, ranging from − 4.52 and − 3.59 ‰ with a mean of − 4.11 ‰ for δ¹⁸O and − 18.02 and − 8.95 ‰ with a mean of − 13.86 ‰ for δ²H. Global meteoritic water line (GMWL) showed a meteoric origin.