Data for: Geo-Resistivity Data Set for Groundwater Aquifer Exploration in the Basement Complex Terrain of North-Central Nigeria

The raw data are the electrical resistivities acquired by Vertical Electrical Sounding (VES) method. They are stored in file vesdata.mat and vesdata.cvs. The data represent changes in the resistivities of rocks and soil materials measured at various depths equivalent to AB/2. Where AB/2, the half of the current electrodes separation ranges from 1 to 100 m. The data acquisition equipment comprised SAS 3000 ABEM Resistivity Meter, four metallic electrodes, electrical cables, measuring tapes, portable Geographic Positioning System (GPS) device, hammer, battery, measuring tapes, a source of direct current (battery) and other accessories. The data is suitable for charactering subsurface rock layer/units and the features that are suitable for groundwater accumulation and mineral exploration. The first column of the MATLAB file contains the values of AB/2, while the rest 85 columns (2 to 86) contain the raw resistivity data acquired at the respective 85 locations. The same arrangement applies to the .CVS file. Appendix II is an excel file. It consists of geo-referencing data (the longitude and latitude), measured at every VES point using portable GPS device. The geo-referencing data are useful for locating the exact point where the electrical resistivity data were acquired. Geo-referencing data are important for field validation of the experiment and for identifying other geophysical data (e.g. Seismic or Ground Penetrating Radar) from the same area, that can be usefully combined in the future, for a better evaluation of the subsurface. Supplementary files III(a) and III(b) are Images data. Stored in .tiff format. These images are the plots of the processed data showing some groundwater aquifer parameters inverted from the raw data. Appendix III(a) is the thickness map of the weathered aquifers, while appendix III(b) is the estimated depths to the bottom of boreholes in the different parts of area. The image data provided useful insights to the hydrogeology of the study area. The data set is precise, repeated experiments at some locations within the area produced similar raw data sets and VES curves. The RMS error between the field data curve and the computer models curves is generally less than 10 percent.

原始数据为通过垂直电测深（VES）方法获取的电性电阻率。这些数据存储在文件vesdata.mat和vesdata.cvs中。数据反映了在不同深度（相当于AB/2）测量的岩石和土壤材料的电阻率变化，其中AB/2是指电流电极间距的一半，其范围介于1至100米之间。数据采集设备包括SAS 3000 ABEM电性电阻率计、四个金属电极、电线、卷尺、便携式地理定位系统（GPS）设备、锤子、电池、卷尺、直流电源（电池）以及其他辅助设备。这些数据适用于表征地下岩石层/单元以及适合地下水积累和矿产资源勘探的特征。MATLAB文件的第一个列包含AB/2的值，而其余85列（2至86列）包含在相应85个位置获取的原始电阻率数据。相同的排列也适用于.CVS文件。附录II是一个Excel文件，它包含了使用便携式GPS设备在每个VES点测量的地理参照数据（经度和纬度）。地理参照数据对于确定电性电阻率数据获取的确切位置至关重要。地理参照数据对于实验的现场验证以及识别同一区域的其他地球物理数据（例如地震或地面穿透雷达）至关重要，这些数据在未来可以有效地结合使用，以更好地评估地下状况。补充文件III(a)和III(b)是图像数据，存储为.tiff格式。这些图像是经过处理的数据的图表，展示了从原始数据反演出的某些地下水含水层参数。附录III(a)是风化含水层的厚度图，而附录III(b)是不同区域钻孔底部估计深度。图像数据为研究区域的地下水文学提供了有益的见解。该数据集精确可靠，区域内部某些位置的重复实验产生了相似的原始数据集和VES曲线。现场数据曲线与计算机模型曲线之间的均方根误差通常小于10%。