The rocks in the Basement Complexof southwestern Nigeria exhibit electrical anisotropy as
a result of their heterogeneous nature caused by weathering, near-surface effects or presence of
fractures. It is known that groundwater yield (Y) in a typical Basement Complex aquifers is related to
its coefficient of anisotropy (). Therefore, it is essential to study the correlation between Y and in
the basement complex. Ten (10) vertical electrical sounding (VES) points using Schlumberger array
were studied in areas underlain by migmatite gneiss and quartzite rocks. The current electrode spacing
(AB/2) varies from 1 m to a maximum spread length of 100 m. The quantitative interpretation of VES
curves was done by using partial curve matching and computer assisted program called WinResist
version 1.0 software. Dar Zarrouk parameters were estimated from the interpreted VES curves and
thus coefficient of anisotropy () was calculated from these parameters. Data on the groundwater
yield at the VES points were also obtained. The results show that as increases, Y also increases with
coefficient of correlation (R2) of 0.86 and 0.79 for migmatite gneiss and quartzite rocks respectively.
To further investigate the relationship between Y and, a regression analysis was performed. The
regression analysis that was performed on the dataset shows that contributes significantly to the
regression models of the two rocks. The relationship between Y and reveals that groundwater yield
could be predicted from the values of in a given locality
