| dc.description.abstract | Abstract The geochemistry of a coastal aquifer was
assessed using statistical and geospatial analysis tools for
the pre-monsoon, rainy and post-monsoon seasons. Data
were obtained from both the field and laboratory analysis
of water samples. Statistical methods such as correlation
coefficients, piper plots, factor analysis and mixing index
were used to gain insights into the geochemistry, while
geospatial tools were used to create contours to understand
the spatial distribution of the measured groundwater
parameters of the coastal aquifer. The measured groundwater levels ranged from -0.84 to 30.08 m above mean
sea level. The Electrical Conductivities and Total Dissolved Solids values were observed to have perfectly correlated with each other. Groundwater salinities were
generally high, as over 94% of the water samples tested
exceeded the WHO drinking water limit of 750 lS/cm and
500 mg/l, respectively. The groundwater pH was generally
slightly alkaline but could be slightly acidic in the rainy
season. The Na?, K?, Mg2?, Cl- and SO4
2- were
observed to have high impacts on the geochemistry and
also had tendencies to form similar trends. EC, TDS and
NaCl values above 1000 mg/l in the groundwater were
observed to generally skew towards the ocean during the
rainy season. The principal process influencing the geochemistry was found to be seawater intrusion, while mineral dissolutions and rainwater percolation play lesser
roles. The aquifer predominantly comprises Na–Cl waters
of marine origin. The study shows the growing importance
and applicability of integrated statistical and geospatial
approaches for better understanding of groundwater and
geochemistry of aquifers. | en_US |
