Uranium Prospecting in the Main Karoo Basin in Retrospect
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URANIUM PROSPECTING IN THE MAIN KAROO BASIN IN RETROSPECT VOLUME I HISTORICAL REVIEW, SUMMARY OF EXPLORATION STATISTICS AND RESOURCE ESTIMATES ON A COMPANY-BY-COMPANY BASIS AND ECONOMIC VIABILITY OF THE MAIN KAROO BASIN by P J van der Merwe ATOMIC ENERGY CORPORATION OF SOUTH AFRICA LTD PRIVATE JAG X256, PRETORIA, 0001 DECEMBER 1986 ISBN-0 86960-836-3 PER-147 PREFACE Prospecting for sandstone-hosted uranium was carried out in the Main Karoo Basin for a period of 17 years. The safety of nuclear power generation fell into disrepute after the Three Mile Island incident in the USA, and resulted in the curtailment of nuclear power orojects. Utility selling of stockpiles created an oversupplled uranium market, and exploration for uranium lost momentum world-wide. Exploration endeavours in the Karoo did cot escape these depressed market conditions and were altogether stopped in early 1985. As it is not foreseen that uranium prospecting will resume in the short term, a report entitled 'URANIUM PROSPECTING IN THE MAIN KAROO BASIN IN RETROSPECT', was compiled to serve as a reference guide for future investigations. Exploration statistics and resource estimates were collated and the report consists of 3 volumes as listed below. Volume I PER-147 Historical review, summary of exploration r catistlcs and resource estimates on a company-by-company basis and economic viability of the Main Karoo Basin. Volume II PIN-854 (B/R) (a) Overview of exploration programmes - Main Karoo Basic orebodie8 A-C (b) Overview of exploration programmes - Main Karoo basin orebodies D-F (c) Overview of exploration programmes - Main Karoo Basin orebodies G-J (d) Overview of exploration programmes - Main Karoo Basin orebodies K-L PER-147 (e) Overview of exploration programmes - Main Karoo Basin orebodles M-P (f) Overview of exploration programmes - Main Karoo Basin orebodies R (g) Overview of exploration programmes - Main Karoo Basin orebodies S-W Volume III PIN-855 (B/R) A farm-by-farm reference guide to exploration company reports in the Geology Department's GEA filing system. PER-147 - 1 CONTENTS Page SAMEVATTING/ABSTRACT 1. INTRODUCTION 1 2. SOUTHERN KAROO REGION 7 2.1 Historical Review and Exploration Statistics 7 2.2 Uranium Resources 16 2.2.1 Anglo American Prospecting Services (Pty) Ltd 21 2.2.2 Essex Minerals Co. 26 2.2.3 Esso Minerals Africa Inc. 26 2.2.4 Industrial Development Corporation of South Africa Ltd 26 2.2.5 Johannesburg Consolidated Investment Co. Ltd 33 2.2.6 Karba Minerals Inc. (Union Carbide/Goldfields Joint Venture) 33 2.2.7 Nevmont South Africa Ltd 36 2.2.8 Phelps Dodge of Africa Ltd 36 2.2.9 Rand Mines Ltd 36 2.2.10 Southern Sphere Uranium (Pty) Ltd 39 2.2.11 Union Carbide Exploration Corporation - Southern Africa 50 2.3 Molybdenum Potential 56 2.4 Economic Viability 58 2.4.1 Data used for profitability analysis 58 2.4.1.1 Ore reserves 58 2.4.1.2 Life-of-mine 59 2.4.1.3 Ore sorting 59 2.4.1.4 Metallurgical recovery 59 2.4.1.5 Uranium and molybdenum prices 5? 2.4.1.6 Capital expenditure 59 2.4.1.7 Operating costs 60 2.4.1.8 Taxation 60 2.4.1.9 Discussion 60 PER-147 - 11 Page SOUTHERN ORANGE FREE STATE 63 3.1 Historical Review and Exploration Statistics 63 3.2 Uranium Resources 63 3.2.1 Rio Tinto Exploration (Pty) Ltd 63 EASTERN ORANGE FREE STATE 64 4.1 Historical Review and Exploration Statistics 64 4.2 Uraniua Resources 68 4.2.1 Karba Minerals Inc. (Union Carblde/Goldfields Joint Venture) 68 QWA-QWA 68 5.1 Historical Review and Exploration Statistics 68 5.2 Uraniua Resources 71 5.2.1 Mining Corporation Ltd 71 CONCLUSIONS 74 BIBLIOGRAPHY 78 LIST OF REPORTS 79 8.1 Anglo Aaerican Prospecting Services (Pty) Ltd 89 8.2 Council for Mineral Technology 80 8.3 Esso Minerals Africa Inc. 82 8.4 Essex Minerals Company 84 8.5 Industrial Developoent Corporation of South Africa Ltd 85 8.6 Karba Minerals Inc. 85 8.7 Johannesburg Consolidated Investment Co. Ltd 86 8.8 Mining Corporation (Pty) Ltd 88 8.9 Nuclear Development Corporation of South Africa (Pty) T.td 88 8.10 Newmont of South Africa Ltd 94 8.11 Phelps Dodge of Africa Ltd 95 8.12 Rand Mines Ltd 95 8.13 Rio Tlnto Exploration (Pty) Ltd 96 PER-147 - iíl 8.14 Southern Sphere Uranlua (Pty) Ltd 98 8.15 Onion Carbide Exploration Corporation - Southern Africa 98 9. LIST OF MAIN KAROO BASIN MAPS IN THE GEOLOGY DEPARTMENT'S LIBRARY 101 LIST OF FIGURES iv LIST OF TABLES vi DISTRIBUTION LIST 122 PER-147 - iv LIST OF FIGURES Page FIGURE l Distribution of the Beaufort Group with the 3 principal uranium areas indicated FIGURE 2 Stratigraphy of the Karoo Sequence,,with uranium deposits indicated FIGURE 3 Annual uranium spot market price against the annual exploration expenditure in the Main Karoo Basin FIGURE A Discovery sequence of the major uranium 8 deposits in the Southern Karoo FIGURE 5 Companies engaged in exploration on an annual basis FIGURE 6 Annual exploration expenditure in the Southern 11 Karoo region FIGUKE 7 Breakdown of expenditure on a company-by-company 12 basis - Southern Karoo FIGURE 8 Metres drilled on a company-by-company basis - 13 Southern Keioo FIGURE 9 Frequency distribution of the recoverable uranium 15 resources for the deposits discovered In the Southern Karoo PER-147 - v Page FIGURE 10 Pie diagram of the RAR -I- EAR uranium 18 resources recoverable at less than $130/kg U discovered by each company In the Southern Karoo FIGURE 11 Cumulative frequency distribution of the 19 average grade of the Southern Karoo uranium deposits FIGURE 12 Cumulative frequency distribution of the 20 uranium grade of Individual samples from the Southern Karoo FIGURE 13 Uranium resources per grade category - 22 Southern Karoo FIGURE 14 Three-dimensional presentation of the 23 number of deposits and their resources per grade range - Southern Karoo FIGURE 15 Locality map of the uranium deposits and BACK PAGE occurrences Xn the Southern Karoo OF REPORT FIGURE 16 Locality map of the uranium deposits 65 in the Southern Orange Free State FIGURE 17 Locality map of the uranium deposits 69 in the Eastern Orange Free State FIGURE 18 Locality map of the uranluo anomalies and 72 orebodies In Qwa-Qwa PER-147 - vi Page LIST OF TABLES TABLE I Summary of the Individual companies' 14 discovery statistics - Southern Karoo TABLE II Uranium resource estimates - Southern Karoo 17 TABLE III Uranium resource estimates and prospecting 24-25 statistics - Anglo American Prospecting Services (Pty) Ltd TABLE IV Uranium resource estimates and prospecting 27 statistics - Essex Minerals Company TABLE V Uranium resource estimates and prospecting 28-32 statistics - Es80 Minerals Africa TABLE VI Uranium resource estimates and prospecting 34 statistics - Industrial Development Corporation of South Africa Ltd TABLE VII Uranium resource estimates and prospecting 35 statistics - Johannesburg Consolidated Investment Co. Ltd TABLE VIII Uranium resource estimates and prospecting 37 statistics - Newnont South Africa Ltd TABLE IX Uranium resource estimates and prospecting 38 statistics - Phelps Dodge of Africa Ltd TABLE X Uranium resource estimates and prospecting 40 statistics - Rand Mines Ltd PER-147 - vli Page TABLE XI Uranium resource estimates and prospecting 41-49 statistics - Southern Sphere Uranium (Pty) Ltd TABLE XII Uranium resource estimates and prospecting 51-55 statistics - Union Carbide Exploration Corporation Southern Africa TABLE XIII Summary of the estimated molybdenum resources 57 of the Southern Karoo TABLE XIV Summary of the production schedule and economic 61 considerations for the four major deposits east of Beaufort West TABLE XV Uranium resource estimates and prospecting 66-67 statistics - Rio Tinto Exploration (Pty) Ltd TABLE XVI Uranium resource estimates and prospecting 70 statistics - Karba Minerals Inc TABLE XVII Uranium resource estimates and prospacting 73 statistics - Mining Corporation Ltd TABLE XVIII Uranium resource estimates - Main Karoo Basin 74 TABLE XIX Comparison of the discovery rate and cost per kilcgram of the different prospecting areas - 75 Main Karoo Basic PER-147 - vlll SAMEVATTING Prospekterlng na uraanhoudende sandsteenafsettings in die Karookon het gedurende 1969 'n a. nvang geneen en in 1985 tot 'n elnde gekom. Alhoevel opsles nog op sekere plase gehou word, word geen verdere ondersoeke In die nabye toekoms voorsien nie. Uraanafsettlngs Is in die sedimente van die Onder-Beaufort-groep en die Elliott - en Molteno-formasie van die Stormberg-groep ontdek. Redelik Versekerde en Geraaode Bykooende Hulpbronne herwinbaar teen 'n koste van minder as Í130/kg U beloop 31 211 t U. Die Suidelike Karoostreek bevat die grootste deel van die hulpbronne, nl. 93 X. Die vier hoofertsliggame oos van Beaufort-Ves, naamlik Rystkuil en Rystkuil-verlengings, Haanekuil, Kareepoort en De Pannen hou 50 X van die Suidelike Karoo-reserwes. Hlerdie vier afsettings hou ook 60 X van die mollbdeenreserwes en vorm die mees lewensvatbare myndistrik in die Karookom. Die ekonomlese lewensvatbaarheid van bogenoemde vier ertsliggame is ondersoek, en teen 'n uraanverkoopprys van R78,05/kg U en 'n Dolibdeenverkoopprys van R13,08/kg Mo in 1985-geldwaarde beloop die verdiskonteerde kontantvloei-opbrengs op belegglngskoers 16,3 X na belasting. Hlerdie af settings het 'n leeftyd van 20 jaar teen 'n jaarlikse produksle van 800 ton uraanmetaal en ongeveer 600 ton molibdeen. Die molibdeenproduksie is genoegsaam om in die land se huidige behoeftes te voorsien. Gesien die feit dat 89 % van die inkooste verkry sal word uit uraanverkope en die huidige ooraanbod van uraan op die wéreldmark, is dit onwaarskynllk dat hierdie afsettlngs op kort tot medium termyn ontgln sal word, tensy 'n drlngende behoefte aan 'n blnnelandse bron van molibdeen ontstaan.