The main population centre of the volcanic Hawaiian-island chain in the north-central Pacific Ocean is on the island of Oahu (population about 900,000) (Figure 1). Oahu depends on ground water, which is mainly produced from coastal aquifers, for its potable-water supply. Oahu has high rainfall, highly permeable aquifers, and a coastal confining layer that results in high heads at the coast and ...

Correlation and cross-spectral analysis can be applied to the study of karstic aquifers to characterize the transformations in these systems between the input function (precipitation) and the output function (discharge). The parameters that can be deduced are the response time, the distinction between quickflow, intermediate flow and baseflow, and the mean delay. This method offers quantifiable...

A new distance-drawdown method for aquifers with anisotropy on the horizontal plane is presented. The method uses scalar transformation to convert to an equivalent, isotropic medium, thus permitting application of the Cooper-Jacob Method. The method is applicable to cases where at least one ellipse of equal drawdown can be delineated but can also be applied where no ellipse can be discerned fro...

A groundwater, sediment and soil chemistry and mineralogical study has been performed to investigate the sources and mobilization process of Arsenic (As) in shallow aquifers of Bangladesh. The groundwater from the shallow aquifers is characterized by high concentrations of Arsenic (47.5–216.8 μg/L), iron (0.85–5.83 mg/L), and phosphate, along with high electrical conductivity (EC). The groundwa...

Many of the world's megacities depend on groundwater from geologically complex aquifers that are over-exploited and threatened by contamination. Here, using the example of Dhaka, Bangladesh, we illustrate how interactions between aquifer heterogeneity and groundwater exploitation jeopardize groundwater resources regionally. Groundwater pumping in Dhaka has caused large-scale drawdown that exten...

Early diagenetic sediment-hosted stratiform copper (eSSC) mineralization results from low-temperature cuprous chloride complexes carried by saline aqueous solution circulating through footwall aquifers. Favorable copper solubilities are attained in moderately oxidizing, near-neutral pH solutions. That specific oxidation level is not determined by co-existence with hematite, with its near-indisc...

There is great concern worldwide about air and water pollution arising from N-fertilizer. Considering the expansion of agriculture and fertilization practices in Argentina, the objective of this study was to determine the effect of Nfertilizers on soil N dynamics and then relationship with nitrate concentration in aquifers. Soil samples were taken during a maize crop cycle in two agricultural f...

Geophysical survey for groundwater was conducted in two newly built halls of residence (hostels) named Dangote and Shehu Idris at the second phase Ahmadu Bello University (ABU), Zaria Nigeria. The vertical electrical sounding (VES) technique resistivity method employed with Schlumberger array seven VES points distributed within hostels. Results showed that 4 to 6 geoelectric layers exist study ...