This study aims at identifying possible correlations between shapes, types of geophysical anomalies and borehole productivity according to geological and hydrogeotogical contexts. The methodology adopted was a two-pro...This study aims at identifying possible correlations between shapes, types of geophysical anomalies and borehole productivity according to geological and hydrogeotogical contexts. The methodology adopted was a two-pronged one--the first step sought to: (1) 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 m3/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〉〉, tttype 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.展开更多
文摘This study aims at identifying possible correlations between shapes, types of geophysical anomalies and borehole productivity according to geological and hydrogeotogical contexts. The methodology adopted was a two-pronged one--the first step sought to: (1) 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 m3/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〉〉, tttype 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.