Masters Theses
Abstract
“The Bushy Park zinc-lead deposit is located in the Northern Cape Province, South Africa. The sulfides are hosted by karst-related breccias that were formed in carbonate shelf deposits of the Neoarchean (2.55 Ga) Campbellrand Subgroup. These rocks are dolomitized completely and silicified partially but have not undergone major metamorphism and thus display remarkable preservation of depositional fabrics. The stratigraphic interval includes the Papkuil and Klippan Formations (> 210 m), a sequence of cyclic microbial laminates interbedded with domed and columnar stromatolites. The Klippan is distinguished from other formations b intense silicification and brecciation. These strata are overlain by the Kogelbeen Formation, consisting of more than 210 m of intertidal facies that occur at the bottom and subtidal facies toward the top. These three formations have undergone slight synsedimentary folding and final stage basin fill towards the end of the Kogelbeen Formation deposition.
The sequence studied is interpreted to represent a third order cycle. The Kogelbeen Formation possibly represents a third order transgression, and the Papkuil-Klippan Formations, a regression. Fourth order cycles are represented by minor shallowing upward sequences throughout the succession and fifth order parasequences are also recognized in the strata immediately above a black shale which represent the contact between the Klippan and Kogelbeen Formations
Replacive dolomite ranges from a relatively fine crystalline planar texture, typical of early diagenetic dolomitization, to a coarse crystalline nonplanar texture, suggestive of epigenetic dolomitization and/or neomorphism of pre-existing dolomite. The nonplanar dolomite is associated with coarse crystalline dolomite and calcite cements that are paragenetically related to quartz cement, abundant pyrobitumen, Zn, Pb, minor Cu, Fe sulfide minerals, and intense brecciation. A distinctive cathodoluminescent microstratigraphy, observed in the carbonate cements, indicates a paragenesis involving multiple stages of cementation and mineralization. All of this suggests a complex fluid history, which includes the emplacement of petroleum. Breccias contain clasts of banded iron formation that is at least Paleoproterozoic in age and therefore suggests a maximum age of 2.5 Ga for the mineralization event.
This study indicates that the Bushy Park deposit underwent depositional, diagenetic, and epigenetic processes similar to Paleozoic and younger Mississippi Valley-type deposits worldwide and share many characteristics in common with Pb-Zn deposits found in the Appalachian Region of North America”--Abstract, pages iii-iv.
Advisor(s)
Jay M. Gregg
Committee Member(s)
Richard D. Hagni
Kevin L. Shelton
Department(s)
Geosciences and Geological and Petroleum Engineering
Degree Name
M.S. in Geology and Geophysics
Publisher
University of Missouri--Rolla
Publication Date
Spring 2002
Pagination
xiv, 174 pages , map
Note about bibliography
Includes bibliographical references (pages 168-173).
Geographic Coverage
Northern Cape Province, South Africa
Rights
© 2002 William Daniel Baugaard, All rights reserved.
Document Type
Thesis - Open Access
File Type
text
Language
English
Subject Headings
Geology -- South Africa
Mines and mineral resources -- South Africa
Thesis Number
T 8016
Print OCLC #
50000411
Recommended Citation
Baugaard, William Daniel, "Stratigraphy and diagenesis of the Paleoproterozoic Bushy Park zinc-lead deposit, South Africa" (2002). Masters Theses. 2115.
https://scholarsmine.mst.edu/masters_theses/2115
Appendix A: Borehole Location Map
Comments
One plate, folded in the back pocket of the manuscript, is provided here as a supplemental file. Due to its large size, this file may take more time to download.
The author thanks the Society of Economic Geologists for its sponsorship of this research.