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A GEOELECTRIC INVESTIGATION OF AQUIFEROUS UNITS IN
PARTS OF DELTA STATE, SOUTHWESTERN NIGERIA
Aweto, K.E
Department of Geology
Delta State University, Abraka.
ABSTRACT
A geoelectric survey
using the electrical resistivity method was employed in investigating
aquiferous units in Abraka, Orerokpe, Oleh and Olomoro in Delta Stat.
Sixteen vertical electrical soundings were carried out in the study are
using the Schlumber configuration. The data was interpreted
quantitatively and qualitatively using the conventional curve matching
and computer iteration method. The results revealed four to six
geoelectric layers, the layers constituting the aquifers do persist over
broad areas. The aquiferous units were mostly confined the (except at
Abraka) and are adequately protected from any direct surface
infiltration of pollutants by the presence of clayey beds in the
surfaces. The units that confined the aquifers have resistively values
ranging from 498.6Ωm to 8, 501.0Ωm with thickness varying between 11.9m
to 84.6m. They are composed of fine, medium and coarse grained sands
and have very good quality groundwater. The aquiferous units occur
between an average depth of 21.0m and 63.6m. The results from this
study were found to be consistent with lithologic logs obtained from
boreholes drilled in the study area. |
