Abstract
Abstract Integrated geophysical methods have been used to investigate the competency of the subsoil. The geophysical surveys conducted involve very low-frequency electromagnetic (VLF-EM) and electrical resistivity (ER) methods (dipole-dipole). ABEM Wadi and Ohmega resistivity meter were used to acquire VLF-EM and ER data, respectively, along two traverses. Station interval of 5 m was used for the VLF-EM survey, while inter-electrode spacing for dipole–dipole was 10 m; the inter-dipole expansion factor (n) ranged from 1 to 5. KHFFILT software was used to generate VLF-EM profiles and pseudosection, while DIPRO software was used for ER. Results from the ER method revealed the pattern of resistivity variations within the study area. The low resistivity values (11–25 Ohm-m) observed at the southern part of the study area could be attributed to changes in clay contents and degree of weathering in the subsurface. The results from the VLF-EM investigation revealed the presence of near-surface linear geologic structures of varying lengths, depths and attitudes, which suggest probable conductive zones that are inimical to the foundation of the road subgrade.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
