10th Inkaba yeAfrica Workshop Mabunda Vincent & Dr C.J.S. Fourie Lord Milner Hotel, Matjiesfontein 29 August – 4 September 2014 Development of a D.C. Resistivity Modelling Laboratory for the Simulation of Wenner, Schlumberger and Dipole-dipole Configurations Mabunda Vincent & Dr C.J.S. Fourie Tshwane university of Technology Faculty of Science Department of Environmental Water and Earth Sciences

OUTLINE Introduction Objectives Constructing a tank and electronics Transferring the geology Laboratory testing Results Conclusion Acknowledgements

Introduction DC. Resistivity is an active geophysical method that measure electric potential associated with subsurface current flow generated by a DC source. The purpose is to determine the subsurface resistivity distribution through measurements on the surface. Configurations that can be used: Wenner, Schlumberger and Dipole-dipole e.t.c

OBJECTIVES Design and development of the scale modelling tank. Testing of the modelling tank by simulating field geology. Comparing modelled results with field results.

Constructing a tank and Electronics CONSTRUCTING THE TANK

Constructing a tank and Electronics CONSTRUCTING ELECTRONICS

Constructing a tank and Electronics CONSTRUCTING ELECTRONICS

Transferring the geology The first layer is made of crushed stones which form bed rock. The second layer is top soil.

Transferring the geology Third layer of normal layered tank Third layer of a faulted tank

Laboratory testing Voltage Scaling Distance Scaling Current Scaling

Laboratory testing  

Results NORMAL LAYERS Wenner Configuration

Results FAULTED LAYER Wenner Configuration Dipole-Dipole Configuration Position of the fault

Conclusions and Acknowledgement This tank simulates geological responses accurately. It enhances student understanding of D.C Resistivity. Acknowledgement Thanks to AEON, Inkaba yeAfrica and my supervisor Dr C.J.S Fourie

Thank you very much for your time Questions Thank you very much for your time