Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526746
Title: Pre-Cambrian structure and the origin of granitoid rocks in south-west Uganda
Author: Barnes, J. W.
Awarding Body: University of London
Current Institution: University of London
Date of Award: 1956
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Abstract:
This thesis gives an account and interpretation of the geology of over four-thousand square miles of south-West Uganda. The Qominant sedimentary rocks are part of the Karagwe-Ankolean System and have been involved in granitisation and orogeny. The area dealt with is part of a curvet orogency belt stretching from Northern Rhodesia to central Uganda; it trends generically N.N.E. but in southern Uganda it begins to turn until it strikes almost due east in central Uganda. In South-\West Uganda the fold-belt is anomalous in direction, branching N.W. from the ma in orogenic strike, and is complicated by belts of N. }..;. cross-folding. Granites have been emplaced in broad anticlinorial, belts, in particular within their individual anticlines where cross-folding was most active. This thesis attempts to explain the geology by showing that lateral compression folded the sediments parallel to the curved geosynclinal axis, but that in South-West Uganda the sediments lay on the curved outer margin of the geosyncline and this margin was pushed southwards during compression to accomodate for its greater length. This resulted in a ~.W. folding direction in the competent rocks high in the system, although lower, more plastic rocks were folded parallel to the geosynclinal margin (N.E.); in intermediate levels, the two directions interferred causing the complicated folding now found. Granitisation affected great anticlinoria 1 belts parallel to N.W. folding, forming wide areas of autochthonous granites in thE lower parts of the Karagwe-Ankolean System. In medium levels, parautochthonous granites were emplaced in individual anticlines of the anticlinoria by volume increase resulting from granitisation, exaggerating them and complicating folding patterns still more. Many such granites are dome-like through the influence of N E. cross-folding which interrupted the N.W. striking anticlines and localised the granites within them. Finally, b¥ an extention of the same processes, small granite stocks were intruded into the highest levels of the system.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.526746  DOI: Not available
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