Groundwater resources exploration of Harrat Khaybar area, northwest Saudi Arabia, using electrical resistivity tomography
Fahad Alshehri, Kamal Abdelrahman
Abstract
Two-dimensional (2D) electrical resistivity tomography (ERT) survey has been conducted in the Harrat Khaybar volcanic field, northeast of Al Madinah Al Munawwarah, Saudi Arabia, to assess the presence of groundwater resources. For this purpose, eleven ERT profiles were generated at six sites oriented north–south and east–west at various lengths between 590 m and 890 m. The ERT data were collected using the Syscal Pro multinode resistivity imaging system with a dipole–dipole array and 5 m of electrode separation. Then, these data have been processed using RES2DINV software to get 2D geoelectric cross-sections. The interpreted 2D geoelectric cross-sections clarified that the Harrat Khaybar occupied by sheets of lava flows underlain by alluvial deposits of gravelly sand and clay. These deposits rest on a Precambrian crystalline rock configuration that has the potential to provide groundwater to the region. Promising water-bearing formations were detected within sub-basaltic alluvial sediments and basaltic flows as well. Moreover, the reported water table in the area has 47 m depth in average with thickness varies between 6 and 200 m. These results correlate well with those of previous hydrogeological studies conducted in Harrat Khaybar. These results are very important for the residents in Harat Khaybar, where enables them to benefit from the groundwater resources in the area for domestic and agricultural purposes.