- This event has passed.
Seminar Series: Dr. Philips Ahzegbobor Aizebeokhai – Near-surface characterisation using geoelectrical resistivity method: field examples, challenges and opportunities
November 5, 2020 @ 12:00 pm - 1:00 pm
Thursday, November 5th via Zoom. Details will be emailed to departmental lists.
The near-surface is a critical geological zone marked with complex interactions between geophysical, hydrological and biogeochemical processes, which control the exchange of mass and energy between the subsurface and the atmosphere. This critical geological zone is significant because it hosts our mineral resources; yields much of our water resources; supports infrastructures, agriculture and ecosystems; influences climate; and serves as the repository for most of our municipal and industrial wastes and contaminants. The efficient and sustainable utilisation of our soils, water and mineral resources require improved understanding of these processes; this can be achieved by quantifying and assessing the heterogeneity of the subsurface and the natural variability of its properties at different scales. Thus, near-surface characterisation provides information for optimising the efficient and sustainable use of the near-surface for water supply, crop production, emplacement of infrastructures and engineering facilities, and ecosystems preservation, as well as for remediation in areas that are contaminated or polluted. Geophysical methods, which provide useful information on the spatial distribution of subsurface properties, are increasingly applied for near-surface characterisation. Electrical resistivity is one of the most versatile geophysical methods for near-surface characterisation; this is because electrical resistivity is proxy to the spatial distribution and temporal variability of many subsurface physical properties, as well as lithologic composition and fluid saturation. Electrical resistivity techniques are cost-effective, non-destructive and minimally invasive; the techniques have been applied in the study of various subsurface characterisation problems including groundwater exploration, landfill and solute transport delineation, determination of compaction and soil horizon thickness, depth to bedrock, and assessment of soil hydrological properties. This presentation highlights the use of geoelectrical resistivity techniques for near-surface characterisation. A variety of field examples, ranging from hydrogeological to environmental and geotechnical investigations, which illustrate the use of geoelectrical resistivity methods for near-surface characterisation, are presented. The challenges with the use of geoelectrical resistivity method for near-surface characterisation and practical ways of addressing the challenges are highlighted. The presentation concludes with the prospects of geoelectrical resistivity and its integration with other geophysical methods in advancing efficient near-surface characterisation and monitoring in the foreseeable future.
Prof. Ahzegbobor Philips Aizebeokhai obtained his B.Sc degree in Geophysics from Edo State University (now Ambrose Alli University), Ekpoma, Nigeria in 1999. He then proceeded to the University of Ibadan, Ibadan, Nigeria where he obtained M.Sc Applied Geophysics in 2003. After working briefly with Strata Search Ltd, Port Harcourt, Nigeria as a geophysicist, he joined Covenant University in 2005 as an Assistant Lecturer and was awarded PhD degree in the same University in 2010. He rose through the ranks and became Professor of Geophysics in 2017.
During his doctoral research, he was a recipient of the CSIR-TWAS Postgraduate Fellowship at National Geophysical Research Institute (NGRI), Hyderabad, India. The fellowship enabled him to work closely with Prof. A. I. Olayinka of the University of Ibadan, Ibadan, Nigeria and Dr V. S. Singh at the Groundwater Research Group, National Geophysical Research Institute (NGRI), Hyderabad, India where he developed 2D and 3D electrical resistivity field designs for near-surface investigations. Though he currently works in an environment marked with lack of research facilities, Prof. A. P. Aizebeokhai has remained committed to his research by maximising available resources in applying geophysical methods for hydrogeological, engineering and environmental investigations. He has authored and co-authored several scientific research articles in both local and international journals. In addition to his research, he is deeply committed to teaching and capacity development for young geoscientists.
In recognition of his commitment and contributions to research and capacity building, particularly in the application of geophysical methods to addressing groundwater and environmental challenges in Nigeria, Prof. A. P. Aizebeokhai was the recipient of the AGU Africa Award for Research Excellence in Earth Science in 2018. His research, teaching and service contributions show great potentials for contributing to the efficient and sustainable management of groundwater and environmental resources in Nigeria and Sub-Saharan Africa.