Electrical resistivity method was used to assess groundwater potential and vulnerability of overburden aquifers at Onibu-Eja active open dumpsite, Osogbo, Southwestern Nigeria. Eighteen Vertical Electrical Sounding (V...Electrical resistivity method was used to assess groundwater potential and vulnerability of overburden aquifers at Onibu-Eja active open dumpsite, Osogbo, Southwestern Nigeria. Eighteen Vertical Electrical Sounding (VES) points and five 2-D imaging profiles established in five traverses at the periphery of the dumpsite were surveyed and analysed. The subsurface comprised of thin topsoil (resistivity 65 - 998 Ωm);heterogeneous weathered layer with resistivity 63 - 333 Ωm and thickness 0.7 - 8.5 m;weathered basement (resistivity 31 - 1253 Ωm and thickness 0.7 - 27.0 m) and fractured/fresh basement (resistivity 36 - 6213 Ωm). The 2-D inverse model of the profiles delineated low resistivity values ranging from 5 to 100 Ωm at a depth range of 10 - 20 m along traverses TR1-TR3 which is attributed to leachate percolation close to the dumpsite. The weathered basement was inclined relative to the dumpsite. The total overburden thickness varies from 6.9 to 33.7 m, with 20 and 40 m generally recommended as productive for groundwater abstraction in Southwestern Nigeria occurring in 61% of the area. Further, about 85% of the weathered layer resistivity values fall within medium groundwater potential (100 - 250 Ωm) and high groundwater potential (>250 Ωm). The ranking of groundwater potential as a function of saprolite (weathered basement) resistivity showed that 72% of the study area is characterized by optimum weathering (20 - 100 Ωm) and is classified as good groundwater potential. Fractured basement covered <30% of the study area. The evaluation of aquifer protective capacity has helped to classify the area into moderate, weak and poor protective capacities with moderate protective capacity zone covering 72%.展开更多
This study is focused on investigation of the resistivity property of polluted soils and the consequent effect on the growth rate of plants. The method involves construction of an inexpensive apparatus for measuring t...This study is focused on investigation of the resistivity property of polluted soils and the consequent effect on the growth rate of plants. The method involves construction of an inexpensive apparatus for measuring the electrical resistivity of polluted soil in the laboratory based on application of Ohm’s law. Some pollutants such as petrol, kerosene and brine were added to the soil samples and the electrical resistivity was determined. The results showed that the quantity of petrol and kerosene added to the soil were directly proportional to the resistivity of the soil while the salt concentration varied inversely with resistivity. On the other hand, the study showed that Kerosene, Petrol and Salt solution of different concentrations have an adverse effect on the growth and development of the bean plants.展开更多
文摘Electrical resistivity method was used to assess groundwater potential and vulnerability of overburden aquifers at Onibu-Eja active open dumpsite, Osogbo, Southwestern Nigeria. Eighteen Vertical Electrical Sounding (VES) points and five 2-D imaging profiles established in five traverses at the periphery of the dumpsite were surveyed and analysed. The subsurface comprised of thin topsoil (resistivity 65 - 998 Ωm);heterogeneous weathered layer with resistivity 63 - 333 Ωm and thickness 0.7 - 8.5 m;weathered basement (resistivity 31 - 1253 Ωm and thickness 0.7 - 27.0 m) and fractured/fresh basement (resistivity 36 - 6213 Ωm). The 2-D inverse model of the profiles delineated low resistivity values ranging from 5 to 100 Ωm at a depth range of 10 - 20 m along traverses TR1-TR3 which is attributed to leachate percolation close to the dumpsite. The weathered basement was inclined relative to the dumpsite. The total overburden thickness varies from 6.9 to 33.7 m, with 20 and 40 m generally recommended as productive for groundwater abstraction in Southwestern Nigeria occurring in 61% of the area. Further, about 85% of the weathered layer resistivity values fall within medium groundwater potential (100 - 250 Ωm) and high groundwater potential (>250 Ωm). The ranking of groundwater potential as a function of saprolite (weathered basement) resistivity showed that 72% of the study area is characterized by optimum weathering (20 - 100 Ωm) and is classified as good groundwater potential. Fractured basement covered <30% of the study area. The evaluation of aquifer protective capacity has helped to classify the area into moderate, weak and poor protective capacities with moderate protective capacity zone covering 72%.
文摘This study is focused on investigation of the resistivity property of polluted soils and the consequent effect on the growth rate of plants. The method involves construction of an inexpensive apparatus for measuring the electrical resistivity of polluted soil in the laboratory based on application of Ohm’s law. Some pollutants such as petrol, kerosene and brine were added to the soil samples and the electrical resistivity was determined. The results showed that the quantity of petrol and kerosene added to the soil were directly proportional to the resistivity of the soil while the salt concentration varied inversely with resistivity. On the other hand, the study showed that Kerosene, Petrol and Salt solution of different concentrations have an adverse effect on the growth and development of the bean plants.
