Resolution enhancement for geoelectrical layer interpretation of electrical resistivity model from composite dataset: Implication from physical model studies

Resolution enhancement for geoelectrical layer interpretation of electrical resistivity model from composite dataset: Implication from physical model studies

The resistivity model results obtained using different electrode arrays differ significantly in delineating subsurface geological structure and the resistivity range of the geological formations. In the present research work we combine the apparent resistivity subsurface data from multiple arrays to provide single resistivity model result of high resolution as ‘composite method’. Initially, the method was tested on physical model data obtained over horizontal marble sheet kept in water. The parameters of target (resistivity, geometry and thickness) noticed in the resistivity model corresponding to composite method are appropriately matching with the true parameters. Finally, the method was applied to the field data from Mahabubnagar, Telangana, India for groundwater studies. The resistivity result achieved using the proposed method has shown a good match with regional hydrogeology and borehole data. The results from this physical model as well as field data suggest reasonable resolution enhancement in composite methodology for resolving the subsurface thin layer(s) in 2D and 3D electrical resistivity tomography and induced polarization (IP) studies for groundwater exploration, prospecting and development.

Figure Caption: Two-dimensional cross-section images obtained using (a) dipole–dipole, (b) Wenner–Schlumberger and (c) composite arrays in lab physical model study over a green marble sheet (l = 60 cm, b = 30 cm, t = 2 cm) at depth d = 3 cm

 

 

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Citation:

 

Rekapalli, R., Kumar, D., and Sarma, V.S., 2019. Resolution enhancement for geoelectrical layer interpretation of electrical resistivity model from composite dataset: Implication from physical model studies, Research Article in Current Science, Indian Academy of Sciences Publication, Vol.116, No.8, pg. 1356 – 1362, published online on 25th April, 2019; doi: 10.18520/cs/v116/i8/ 1356-1362