Investigating linkages between engineering and petrophysical properties of unconsolidated geomaterials and their geoelectrical parameters.

摘要

The need for an improved ability to "see into the earth" has resulted in the use of geophysical techniques, especially the electrical resistivity method, in engineering and environmental investigations. The major challenge in the use of electrical resistivity measurements however is the interpretation of the electrical response. This is due to the lack of adequate understanding of the relationships between the physical factors controlling the engineering behavior of geomaterials (earth materials) and their measurable electrical parameters. This research work therefore sets out to investigate the linkages between engineering and petrophysical properties of geomaterials and their geoelectrical parameters and to provide a methodology by which the engineering behavior of the subsurface can be predicted non-invasively. This goal is achieved through the development of laboratory equipments and the conduction of both laboratory and field studies. The laboratory experiments involve the measurement of the complex resistivity responses of natural and artificial soil samples under varying effective stress conditions. The field study involves the characterization of subsurface fracture parameters from field electrical measurements in complex fractured terrains at selected farming communities in Ghana.;The results from this study improve on our knowledge and understanding of the influence of fundamental engineering properties of geomaterials on their electrical responses. The results will aid in the interpretation of field electrical measurements and provide a means for engineering properties of geomaterials to be estimated from measurable electrical parameters. It will also contribute towards using non-invasive electrical measurements to assess and monitor the stability conditions of soil units and examine the role of subsurface fractures in the contamination of groundwater resources in complex fractured terrain.