Please use this identifier to cite or link to this item: http://hdl.handle.net/2440/86357
Type: Thesis
Title: 1. The geology and petrography of an Archaean inlier, south of Normanville. 2. The origin of the 'Houghton' granulite.
Author: Davies, M. B.
Issue Date: 1972
School/Discipline: School of Earth and Environmental Sciences, Geology & Geophysics
Abstract: 1. Detailed mapping established definite rock units within the Archaean inlier south of Normanville. The distribution of the rock types is suggestive of a major antiformal structure. Only metamorphic layering is recognised in the area. The first Archaean orogeny produced this layering and reached upper amphibolite grade of metamorphism as defined by the minerals sillimanite, garnet, diopside and scapolite. The temperature and pressure conditions were ~750C and 2-3 Kbars. This was established using mineral assemblages and the presence of considerable partial melting, pegmatitic masses and migmatites. This same orogeny was also responsible for the development of a strong schistosity, which was always parallel to the metamorphic layering. A Proterozoic orogeny produced a strong crenulation of the schists. This crenulation is parallel to the fold axis of a major antiform which plunges 35deg to 138deg. The deformation reached biotite grade of metamorphism as shown by the minerals biotite, sericite and epidote, which, commonly replace the higher grade minerals. An antiform overturned to the west was the major structure. Its under limb was sheared away, so that the inlier represents the eastern limb only. The western outcrops of the inlier represent the shear zone. 2. Geochemical analyses of the Houghton granulite suggest a sedimentary origin. This, coupled with its conformability with the surrounding rocks, and its association with a zircon rich meta-quartzite, support this conclusion.
Dissertation Note: Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Earth and Environmental Sciences, 1972
Where: Gawler Craton, Normanville & Houghton Inliers, South Australia
Keywords: Honours; Geology; Precambrian; metamorphism; structure; petrography
Description: This item is only available electronically.
Provenance: This electronic version is made publicly available by the University of Adelaide in accordance with its open access policy for student theses. Copyright in this thesis remains with the author. This thesis may incorporate third party material which has been used by the author pursuant to Fair Dealing exceptions. If you are the author of this thesis and do not wish it to be made publicly available, or you are the owner of any included third party copyright material you wish to be removed from this electronic version, please complete the take down form located at: http://www.adelaide.edu.au/legals
Appears in Collections:School of Physical Sciences

Files in This Item:
File Description SizeFormat 
01frontGeoHon.pdfTitle page, table of contents, abstract62.44 kBAdobe PDFView/Open
02wholeGeoHon.pdfWhole thesis (as available)7.68 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.