International Uranium Resources Evaluation Project - Iurep
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International Atomic Energy Agency D P. A INTERNATIONAL URANIUM RESOURCES EVALUATION PROJECT - IUREP - IUEEP ORIENTATION PHASE MISSION REPORT REPUBLIC OP BURUNDI Mr. W. Gehrisch JUNE 1983 Mr. M. Cbaigne DiSCLAiMER Portions of this document may be iiiegibie in electronic image products. images are produced from the best avai!ab!e origina! document TABLE OF CONTENTS A. SUMMARY, CONCLUSIONS AND RECOMMENDATION 1 B. INTRODUCTION 2 1. Terms of Reference 2 2. General geography 2 3. Climate 4 4. Population and main cities 8 5. Administrative regions 8 6. Official language, Public holidays 8 7. Transport and Communication 10 8. Available maps and Air photographs 10 9. Administrative bodies concerned with the regulation of geological and mining activities including those on uranium 14 10. Legislation on uranium exploration and mining ..... 20 C. GEOLOGICAL REVIEW 22 1. Introduction 22 2. Geological History 26 2.1. Archean 26 2.2. Lower Proterozoic 26 2.3. Middle Proterozoic 31 2.4. Upper Proterozoic 35 2.5* Paleozoic-Mesozoic 43 2.6. Tertiary to recent 43 2.7. The structural provinces of Burundi 43 3. Metallogenesis 45 D. NON URANIUM MINING IN BURUNDI 49 1. Tin, Tungsten, Columbo Tartalite of Northern Burundi 49 2. ' Bastnaesite ore of the Gakara district. 49 5. HISTORY OF URANIUM EXPLORATION 52 1. Introduction 2. The U.N.D.P./D.T.C.D Mineral Project 52 2.1. Objectives 52 2.2. Exploration programmes 52 2.3. Results 54 3. The B.R.G.M. Mineral Survey 64 F. OCCURRENCES OF URANIUM 66 1. Introduction 66 2. Kiganda occurrence 66 3. Musigati 70 4. Mparamirundi andKigambi 74 5. Matongo 75 6. Buhoro-Muliza 76 G. IUREP MISSION FIELD RECONNAISSANCE 77 1. Introduction 77 2. Kiganda.... 77 3. Buhoro-Muliza 77 4. Mparamirundi 78 5. Matongo 78 H. FAVOURABLE AREAS FOR SPECULATIVE POTENTIAL 79 1. The Archean complexes 79 2. The Ruzizian versus the Burundian 79 3. The Malagarasian (upper Proterozoic) 54 4. Paleozoic -Mesozoic (Karoo) 85 5. Cenozoic 85 I. URANIUM RESOURCES POSITION 36 Speculative Potential J. RECOMMENDATIONS FOR FUTURE EXPLORATION 3Q 1. Introduction 39 2. Work in the different areas and categories 39 K. ACENOI-JLEDGEMENTS L. REFERENCES LIST OF FIGURES Pace Fig. 1 Location map 3 Fig. 2 Physical geography 3 Fig. 3 (climat I) Temperature zones and Annual rainfall 6 Fig. 4 (climat H)Climatic regions 7 Fig. 5 Administrative divisions ....... 9 Fig. 6 Key-map of Topographic maps at 1:50.000 scale 11 Fig. 7 Key-map of Topographic maps at 1:100.000scale 12 Fig. 8 Chart of Available geological maps at 1:100.000 scale 13 Fig. 9 Organization of the "Ministere des Travaux Publics, de l'Energie et des Nines" 15 Fig. 10 Organizational structure of the U.N.D.P. Mineral project 17 Fig. 11 Archean complexes in Burundi 25 Fig. 12 Tectonic sketch map showing relations between the Klbaran-Urundian and the Ubendian-Ruzizian27 Fig. 13 Geology of Burundi 30 Fig. 14 Structural sketch of south east Congo Zaire and neighbouring regions 36 Fig. 15 Sketch man of the Malagarasian (Burundi) and Bukoban (Tanzania) 37 Fig. 16 Rift system in Eastern Africa 44 Fig. 17 Mineral occurrences and radiometric anomalies in Burundi 46 Fig. 18 Location diagram of 1971 Hunting Spectrometer Survey 55 Fig. 19 Key map showing areas surveyed by Hunting Geology and Geophysics in 1974- 57 Fig. 20 1981 B.G.R. Airborne Survey showing areas surveyed and methods employed 60 Fig. 21 1981 B.G.R. Airborne Survey showing delinea- tion of sectors I to XI 61 Fig. 22 Location of uranium occurrences 66 Fig. 23 Kiganda - Trench 4 69 Fig. 24 Musigati - Trench 4 - Drill hole 73 Fig. 25 Approximate geochronological distribution of sedimentary uranium deposits (1979) 79 LIST OF TABLES Page Table 1 Information of the UNDP Geochemical Laboratory 18 Table 2 Information of the UNDP Geophysical Unit 19 Table 3 Stratigraphy of the Ruzizian in the type area 28 Table 4 General Stratigraphy of the Ruzizian 28 Table 5 Stratigraphy of the Burundian in the eastern part of Rwanda and Burundi 32 Table 6 Stratigraphy of the Burundian in the western area (western Rwanda and Burundi and southern Kivu) 33 Table 7 Correlations of local stratigraphic sequences of Rwanda and Burundi ... 34 Table 8 Stratigraphy of the Bukoban in Tanzania 39 Table 9 Stratigraphy of the Malagarasian of Burundi 40 Table 10 Simplified succession and subdivision of the Katangan in Katanga and the Copperbelt of Zambia 42 Table 11 Breakdown of Rare Earths in the Bastna- esite ore 49 Table 12 Production of Bastnaesite ore for the period 50 1970-1973 Table 13 Statistics regarding Production and Exportation of Minerals $1 Table 14 Studied zones (1974 Hunting Survey) 58 Table 15 Speculative Resources of Burundi 38 Table 16 TUEEP Mission proposed programme, summary and costs 9? LIST OF APPENDICES I Mining and Petroleum Act. (Code Hinier et Petrolier) 1976 II Investment code (Decret-Loi -Code des investissements)1979 III Main Results -UNDP Project BDI/68-005 IV UNDP - Project BDI/71-517/7 - Main Results V Useful addresses and information. *) This material, not contained in the draft report, is available for inspection in Vienna. PREFACE The mission was undertaken by two consultants, Mr. W. Gehrisch and Mr. M. Chaigne. They "both commenced their investigations in Burundi on 6 Hay 1985 and completed their work on 3-^ June 1983. A total of two days was spent in the field by the consultants. - 1 - A. SUMMARY, CONCLUSIONS AND RECOMMENDATIONS 1. The IUREP Orientation -ohase mission to Burundi believes that the S-oeculatives Resources of that country fall "between 300 and 4100 tons uranium oxide but a less speculative appraisal is more likely between 0 and 1000 tons. 2. There has been no uranium production and no official estimates of Uranium Resources in Burundi. Past exploration mainly dating from 1969 onwards and led the UNDP Mineral project has indicated a limited number of uranium occurrences and anomalies 3. The speculative uranium resources are thought to be possibly associated with potential unconformity related vein-like deposits of the Lower Burundian. 4. Other speculative uranium resources could be associated with granitic or peribatholitic environments preferably in areas of low to medium grade metamorDhism or at the (faulted) contacts between sedimentary arkoses and gabbroic intrusives. Uranium could also be recovered as a by product of -phosphate - mining at Matongo. 5. The results gained from the recent C1981) BGR Airborne S-oectrometric, Electromagnetic and magnetometric survey should helD delineating prospective areas especially in areas blanketed by the Malagarasian, or at the contacts between Burundian and Malagarasian. 6. Suggestions are made by the TUREP consultants that, on the ground of geological reasoning, a series of targets be defined and that -orosDective areas be selected on the basis of rock geochemistry and regional stream sediment geochemistry. Strategies for prospecting are therefore proposed in order of increasing exoloration costs and expected tonnage of U^O 7. The TUREP Orientation Mission suggests that over a period of five years some 3 to 4.5 millions U.S. Dollars be suent on surface and subsurface exploration. B. INTRODUCTION *2 - 1. Terms o^ Reference The basic objective of the International Uranium Resources Evaluation project flUREP^ is to "Review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for the discovery of additional uranium resources and to suggest new exploration efforts which might be carried out in promising areas in collaboration with the countries concerned". Therefore, the scope of the IUREP orientation phase Mission to Burundi was : 4- to review all datas on *oast exploration in Burundi, + to develop a better understanding of the uranium potential of the countrv, + to make an estimate of the speculative resources* of the countrr, + to make recommendation as aonrcoriate on the best methods or techniques for evaluating the resources in the favourable areas and for estimating possible costs as well, + to compile a report which could be immediately available to the Burundian authorities. 2. General Geosrraphv The Republic of Burundi is located in the heart of Africa, about 300 Em south of the Equator, 1200 Km from the Indian Ocean and more than 2200 Km from the Atlantic Ocean (Figure 1). The country is more precisely located between latitudes 2°3O'S and 4°29'S, and longitudes 28°50' and 3O°53'3O" and is bordered on North by Rwanda, on South East by Tanzania, on West by Zaire and Lake Tanganyika. Speculative Resources refers to uranium in addition to Estimated additional Resources that is thought to exist mostly on the basis of indirect evidence and geological extrapolations, in de-oosits discoverable with existing exploration techniques. The location of deposits envisaged in this category could generally be spe- cified only as being somewhere within a given region or geological trend. - 3 - StTUATlON DU DANS LE CADRE STRUCTURAL AFRtCAtN <^MM^</? R 8LACK (1967!. GRANT <197:i G CWOUBERTetA fAUf)6MURET)]975!. REGAN el *<. 11975!. B BESSOL6S ot R THOMPErTE l!98Oi e< 'MtmynMtMM <n^</<K /Hf M 30RNUAT. G HOTTIN ei G J0UHD6 ARCHITECTURE OU SOCLE AFRtCAtN iuc!tf precamorten C D hntertaur) --' s.t cuuvertufe '600 M A (ft p!us 51X3 Fig. 1 Location ma*o - /i. - Burundi is one of the smallest land-locked countries in Africa and is roughly triangular in shape (180 X 200 Km\ It covers an area of 27,354 square kilometres f10,747 sq.miles^. Burundi coincides with the raised region on the eastern edge of the Western Rift valley and as such, its relief rises to 2600 metres dominated "by a precipitous cliff and the tectonic trench in which Lake Tanganyika lies.