Title page for ETD etd-09022005-114239


Document Type Doctoral Thesis
Author Sumner, Paul
URN etd-09022005-114239
Document Title On the geomorphic evidence for a late quaternary periglaciation of the main escarpment region of eastern southern Africa
Degree D Phil (Geography)
Department Geography, Geo-Informatics and Meteorology
Supervisor
Advisor Name Title
Dr K I Meiklejohn Committee Chair
Keywords
  • geomorphology
  • geology sratigraphic periglacial Africa Southern
  • Africa Southern
Date 2003-09-01
Availability unrestricted
Abstract
Conflicting reports from geomorphic studies appear in the literature describing the environment of the southern African Main Escarpment region adjacent to the Lesotho Highlands during the cold phases of the Late Quaternary. Evidence cites limited glaciation and/or periglacial conditions with or without permafrost. The thesis emphasises debates and presents arguments for alternative interpretation of landforms previously described in the literature as indicative of specific cold environments. Field investigations into the distribution and characteristics of openwork accumulations in southern Africa show that blocky accumulations are found within a range of climatic conditions, including arid and semi-arid environments. Mode of emplacement is highlighted as the critical factor in association with a periglacial environment. Relict openwork block accumulations in the Lesotho highlands area around Thabana Ntlenyana, the highest summit in the escarpment range, supports the contention for a relatively arid periglacial environment during the Late Pleistocene. Findings militate against either deep snow cover or localised glaciation of insolation-protected south-facing slopes. The evidence for periglacial conditions is supported by the presence of relict sorted patterns that indicate deep seasonal freeze. Contemporary soil temperature monitoring indicates a near-surface current seasonal freeze of two and a half months which would have been prolonged and deepened under depressed temperature. No specific evidence for periglacial conditions is found for the escarpment region in the Amatola mountains.

2003 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.

Please cite as follows:

Sumner, P 2003, On the geomorphic evidence for a Late Quaternary periglaciation of the main escarpment region of eastern southern Africa, DPhil thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-09022005-114239/ >

H1186/ag

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  thesis.pdf 2.85 Mb 00:13:11 00:06:46 00:05:56 00:02:58 00:00:15

Browse All Available ETDs by ( Author | Department )

If you have more questions or technical problems, please Contact UPeTD.