Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.641204
Title: Magnetotelluric studies of the Zambezi Valley mobile belt, Northern Zimbabwe
Author: Bailey, David
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 1998
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Abstract:
The Mana Pools and Lower Zambezi Karoo sedimentary basins lie within the Zambezi mobile belt in northern Zimbabwe. The subsurface apparent resistivities measured at both locations are extremely low. This thesis models the resistivity structure of these two basins and the underlying material. New and pre-existing magnetotelluric data and the available seismic reflection data are used to determine the basin structure and the depth of the electrical basement. Long period magnetotelluric data were collected at 5 stations along a 60 km profile running north-south across the Mana Pools basin and onto the escarpment to the south. These data are used to augment an existing audio frequency dataset from the same area. After processing of both datasets the estimated impedance tensor is decomposed, showing that the resistivity structure of the Mana Pools basin can be modelled two dimensionally. Minimum structure models for the Mana Pools and Lower Zambezi basins are produced and compared, the latter obtained from a pre-exiting magnetotelluric dataset. There are significant differences between the structure of the two basins. The major conductive feature in the Mana Pools basin is contained within the Upper Karoo sedimentary layer and does not extend into the basement below, which is, however, of an extremely low resistivity for basement rock. The electrical basement in the Lower Zambezi basin is not detected. A good conductor is again found in the Upper Karoo sediments but extends to below 11.6 km, within the gneissic rocks of the seismic basement. The resistivity structure of the Mana Pools basin is well modelled as a series of resistive layers whose boundaries are defined by the seismic data.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.641204  DOI: Not available
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