Optimizing the Interpretation of Sub-surface Resistivity in Relation with Borehole Productivity in Basement Area Applied to Seno Province (Burkina Faso)

Abstract

This study aims at identifying possible correlations between shapes, types of geophysical anomalies and borehole productivity according to geological and hydrogeological contexts. The methodology adopted was a two-pronged one-the first step sought to: (i) interpret the electrical resistivity values from horizontal profiling and vertical electrical sounding implemented in Seno province that preceded the drilling of 513 boreholes; (ii) interpret data from pumping tests carried out on boreholes having a discharge superior to 1 m 3 /h ("positive borehole") by using Cooper-Jacob's method. In the second step, according to geology, authors tried to identify possible correlations between each of the qualitative geophysical parameters: «shape of anomaly», «type of anomaly» and «type curve» on the one hand, and hydrogeological parameters such as discharge, alteration thickness, transmissivity and saturated level on the other. The results of this study have shown that the chances of having a positive borehole in Seno province are higher when the type of anomaly is TCC (80%), shape of anomaly is "W" and when type curve is "H" (80%) for all geological formations. Granitic formations are those that record higher discharges while schists record high transmissivity values.

Identification of hydrogeological and geoelectrical parameters influencing the productivity of boreholes in the commune of Daloa (Central-Western of Côte d'Ivoire)

“…They allowed the observation of wide and narrow conductive compartments. From a hydrogeological perspective, these anomalies in the resistivity profile anomalies reflect highly fractured zones that may be preferred locations for productive drilling in crystalline rocks [ [35] , [36] , [37] , [38] , [39] ]. Numerous borehole failures can be observed when these anomalies are deflected in crystalline rocks.…”