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Sedimentology and Stratigraphy of the Fig Tree Group, West Limb of the Onverwacht Anticline, Barberton Greenstone Belt, South Africa

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Sedimentology and Stratigraphy of the Fig Tree Group, West Limb of the Onverwacht Anticline, Barberton Greenstone Belt, South Africa Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1986 Sedimentology and Stratigraphy of the Fig Tree Group, West Limb of the Onverwacht Anticline, Barberton Greenstone Belt, South Africa. Bruce William Nocita Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Nocita, Bruce William, "Sedimentology and Stratigraphy of the Fig Tree Group, West Limb of the Onverwacht Anticline, Barberton Greenstone Belt, South Africa." (1986). LSU Historical Dissertations and Theses. 4315. https://digitalcommons.lsu.edu/gradschool_disstheses/4315 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS While the most advanced technology has been used to photograph and reproduce this manuscript, the quality of the reproduction is heavily dependent upon the quality of the material submitted. For example: • Manuscript pages may have indistinct print. In such cases, the best available copy has been filmed. • Manuscripts may not always be complete. In such cases, a note will indicate that it is not possible to obtain missing pages. • Copyrighted material may have been removed from the manuscript. In such cases, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, and charts) are photographed by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each oversize page is also filmed as one exposure and is available, for an additional charge, as a standard 35mm slide or as a 17”x 23” black and white photographic print. Most photographs reproduce acceptably on positive microfilm or microfiche but lack the clarity on xerographic copies made from the microfilm. For an additional charge, 35mm slides of 6”x 9” black and white photographic prints are available for any photographs or illustrations that cannot be reproduced satisfactorily by xerography. 8710578 Nocita, Bruce William SEDIMENTOLOGY AND STRATIGRAPHY OF THE FIG TREE GROUP, WEST LIMB OF THE ONVERWACHT ANTICLINE, BARBERTON GREENSTONE BELT, SOUTH AFRICA The Louisiana State University and Agricultural and Mechanical Ph.D. Col. 1986 University Microfilms International 300 N. Zeeb Road, Ann Arbor, Ml 48106 ft PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . 1. Glossy photographs or pages i / 2. Colored illustrations, paper or print _______ 3. Photographs with dark background / 4. Illustrations are poor copy ______ 5. Pages with black marks, not original copy ______ 6. Print shows through as there is text on both sides of p a g e _______ 7. Indistinct, broken or small print on several pages )/ 8. Print exceeds margin requirements ______ 9. Tightly bound copy with print lost in spine _______ 10. Computer printout pages with indistinct print _______ 11. Page(s) ___________ lacking when material received, and not available from school or author. 12. Page(s)____________ seem to be missing in numbering only as text follows. 13. Two pages num bered . Text follows. 14. Curling and wrinkled pages ______ 15. Dissertation contains pages with print at a slant, filmed as received _________ 16. O t h e r ______________________________________________________________________ University Microfilms International SEDIMENTOLOGY AND STRATIGRAPHY OF THE FIG TREE GROUP, WEST LIMB OF THE ONVERWACHT ANTICLINE, BARBERTON GREENSTONE BELT, SOUTH AFRICA A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillm ent of the requirements of the degree of Doctor of Philosophy in The Department of Geology by Bruce W. Nocita B.S., Colorado State University, 1974 M.S., San Diego State University, 1977 December, 1986 ACKNOWLEDGEMENTS I would like to thank Dr. Donald R. Lowe for serving as committee chairman and assisting in the completion of this project. Drs. Gary Byerly, Jeff Hanor, Dag Nummedal and Jeff Nunn reviewed the entire manuscript and provided many important and useful suggestions for improvement. Barbara Ransom, Michael DiMarco, Patti P hillips, Gail Fisher, Danny Worrell, Amitava Roy, Maud Walsh, Kathy Duchac and Sam Upchurch all read portions of the manuscript and made helpful suggestions; to each of them goes my heartfelt appreciation. I would also like to thank Elizabeth Chinn, John Eldridge, and Ezat Heydari for their assistance in the completion of this project. My deepest appreciation goes to Barbara Ransom who helped me through much of the field work for this project and who provided needed encouragement and support. The final stages of completion of this project involved many long and sometimes frustrating hours of work. Throughout this time Heather Lane provided help and encouragement and took care of a lot of l i t t l e things that would otherwise have occupied my time. This research was supported in part by NSF grants EAR 82-06015 to Lowe and EAR 79-19907 to Byerly and Lowe, and an ARCO fellowship to the author. TABLE OF CONTENTS Page ACKNOWLEDGEMENTS i i LIST OF TABLES ..............................................................................................................v LIST OF FIG U R E S............................................................................................................vi ABSTRACT............................................................................................................................viii INTRODUCTION ............................................................................................................. 1 REGIONAL GEOLOGY ...................................................................................................... 3 P l a t e ............................................................................................................................7 STRATIGRAPHY........................................................................................................................... 8 STRUCTURE..........................................................................................................................* 14 PETROGRAPHY..........................................................................................................................18 LITHOFACIES AND ENVIRONMENTS OF DEPOSITION........................................................24 Formations and Lithofacies .................................................................... 24 Lithofacies A j .......................................................................................26 Lithofacies A 2 .......................................................................................30 Depositional Model - Formation A .......................................... 35 Lithofacies B ^ .................................................................................. 3 6 Lithofacies B 2 .......................................................................................41 Lithofacies B ^ .......................................................................................49 Lithofacies .......................................................................................50 Lithofacies C ^ .......................................................................................53 Fan Delta M odel ....................................................................................... 74 Lithofacies C2 .......................................................................................83 DIAGENESIS AND METAMORPHISM.......................................................................................92 GEOCHEMISTRY.........................................................................................................................99 i i i TABLE OF CONTENTS (Continued) Page DISCUSSION AND CONCLUSIONS..................................................................................... I ll BIBLIOGRAPHY.......................................................................................................................126 APPENDIX..............................................................................................................................137 Stratigraphic Section Localities ...................................................... 138 Stratigraphic Section Descriptions .........................................................140 VITA .....................................................................................................................................169 iv LIST OF TABLES Table Page 1. Major lithostratigraphic units and lithofacies . 10 2. Summary of point count data .................................................................... 19 3. Characteristic features of Lithofacies ............................. 56 4. Clast composition for pebbles and cobbles of Lithofacies C ^ ...............................................................................................59 5. Comparison of alluvial-fan/fan-delta, submarine-fan, and Fig Tree conglom erates ...................................................................67 6. Characteristics of different fan-delta models. 81 7. Chemical analyses
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