Abstract

The electrical resistivity investigation conducted on a property in Cu Jut, Dak Nong, had the overarching objective of assessing the groundwater potential for coffee cultivation. This local-scale project employed a comprehensive approach, involving three Vertical Electrical Sounding (VES) points, four 2-D imaging profiles spanning four survey lines, and a sophisticated 3D visualization for in-depth area analysis. The quantitative interpretation of VES curves was a pivotal aspect of the study, executed with precision through partial curve matching and computer-assisted 1-D forward modeling using IPI2 win software. This meticulous approach facilitated the identification of four distinct geological layers in the study area. The topsoil layer, although shallow, was found to lack significant hydrogeological properties. Below this, a partially weathered basalt layer emerged as a small aquifer unit, exhibiting thicknesses typically ranging between 10 to 15 meters. However, its hydrogeological significance was moderate. The interleaved arrangement of porous and tight basalt layers, constituting the primary aquifer, emerged as a key finding. Characterized by resistivity values generally below 300 ohm-meters, this aquifer displayed low permeability and porosity, suggesting a limited capacity for groundwater storage. The basement rock marked the concluding layer in the geological profile. Integrating data from both 2-D imaging profiles and 3-D visualization, the study delved into assessing potential water depth and estimating water volume. Utilizing contour maps, the research also identified optimal locations for well drilling. In essence, the study's findings point towards the interleaved porous and tight basalt layer as the primary aquifer with substantial potential for groundwater supply. Contrarily, other geological layers were deemed to have limited hydrogeological significance. This holistic assessment, supported by advanced resistivity methods, provides valuable insights for sustainable water resource management, particularly in the context of coffee cultivation in Cu Jut, Dak Nong.