I U R E P Orientation Phase R E P O R T G H a 1\F A
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International Atomic Energy Agency DRAFT I U R E P ORIENTATION PHASE REPORT G H A 1\F A MR. JEW-PAUL GUELPA MR. WOLFRAM TO GEL December 1982 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document UTTEENATIOITAL URANIBK RESOURCES. EVALUATION PROJECT -IURBP- IUSSP ORIENTATION FHAS3 MISSION REPORT BSPTOLIC OP GHANA Dr. J.Fo Guelpa December, 1982. Dro "W. Vogel PREFACE mission, was undertaken, by two consultants, Dr. JoP. Guelpa and Dr. W, Vogel, both, commenced the investigations in Ghana on 5th November, 1982 and completed their work on 16th December, 1982. A total of three days was spent in the field by the consultants* 1. Terse of Ilsferenie .. ., 5 2. General Geography .. .. 4 3. Clirate .. ... 7 4. Population aril I-lain Cities .. .. 9 5. Administrative Regions .. .. S- 6. Official Language, Public Holidays and System of Eeasureaervfc .. ., ll 7. Transport and Consronicatipn .. .. 11 8. Available "aps and Air Photographs .. 12 c. ITCK UB^ITK ICIITIKG n; GH^A • .. .. 13 1. Overview .. .. 13 2. Dianond .. ,. 15 3. Gold .. .. 17 . • 4. Batfzite .. • .. 'IS 5. Manganese .. .. 18 D. IBGI3LATICH ON UEAiTITJK EXPLCHASCtf AlTD XIIIDTG 19 3. KATIOKAL CAFACITI PCS URAFIUI! SXPLORATIC1T AIT3 D272L0P- 1. Ghana Atoiaic Energy CoEE&ssion .. 20 2. Ghana Geological Survey .. .. 22 3. Universities .. .. 24 F. GnOL'OGIC/i 3ST.12r.7 . .. 25 1. Introduction .. ' .. 25 2. The 'vest African Shield Area .. .. 27 2.1 Birician Systec .. .. 27 2.2 Eburnean Granites .. .. 32 2.3 Taria-;aian System .. .. 35 3. Sie Kobile Belt ... .. 3S 3.1 Dahoneyan System •• •• 35 3.2 ?cgc Series •• •• 4C 3 .3 Buen. Pcrsiticn • • • • 40 3.4 Toltaian System •• •• '43 3o5 Synthesis of the 1'obile Belt •• . 50 4» Accra and Sekcndi Series •• •• 55 5. Cretaceous to recent Coastal Basins •• 57 6. Ketallogeny •• •• . 60 G. HISTCHT CF USAKHJE SXPLOPJ.TIOK BT GEAKA • • ' 63 1. Carbome Survey by the United Ilingdom Geological Survey .. ## 63 2. Airborne Survey by Hunting Surveys Ltd. 64 3. TJraniua Prospecting by Uranerzbergbau-GmbE 66 4. TJraniuci Prospecting by the IJL3A ' •• • 71 5. Track Etch Survey by the Ghana Atonic Energy ComEission ... .. 72 6. Past Uranium Sxploration Expenditures in Ghana 72 E. EADI0JLCE7E JiPOKALiaS, URAEITJE OCCUBEnTCSS JCT 2SSCU2C3S 73 1. Anooalies and Assessment .. .. 73 2. Uranium Occurrences .. •• 80 3« Uranium Resources Position ,^.. 82 I. URANIUM 0CCU2E3NCE3 A!TD "DEPOSITS HT T.-n33TEHN GCIT3)Ti,TA!U 82 J. TO3SP JUSSION HELD HEC01SUIS3A2TCS .. • 86 K. TJEAITITU: P0TS1ITIAL CF GSjJlA .. .. 88 1. Introduction •. • • 88 2» Mobile Belt .. .. 88 3. Yoltaian System .. .. 91 4. Zbumean Granites ., .. 95 5. Tarkvaian ., .. 33 6. Coastal Basins .. .. 99 7. Birisian .. .. ICO L. SP3CTJIATITO UEAKIUK E3SCURG2S .. 102 II. B3C0I-3-32DID PSCGHAI^JG ?CR FOTUIS ZZFL0EATIC17 103 1. Introduction .. .. 103 2. Large Scale Prograsae .. .. 103 3. Snail Scale ^rogranane .. .. 1Q6 4. Exploration Cost Estinate .. 107 5. Policy Options for the Implementation of Recommendations .. .. 109 TTS .. .. 110 0. ESF3FJ3ITCE3 .. .. Ill Pare Fig. I Location Kap of Ghana. .. .. 5 Fig. 2 Physiographic Regions of Ghana .. 6 Fig. 3 Precipitation !*ap of Ghana .. 8 Fig. 4 Administrative Regions of Ghana .. 10 Fig. 5 Producing Kir.es and Mineral Occurrences of Ghana .. .. 14 Fig. 6 Organisational Structure of the Ghana Atomic Energy Commission .. .. 21 lig. 7 Organisational Structure of the Ghana Geological Survey Department .. 23 KLg. 8 Blajor Structural Domains of T,vest Africa after BASS (1980) .. .. 26 51g. 9 Geology of Ghana .. .. 28 Fig. 10 Cross Section of the Panafrican Orogen-after GSAKT (1969) .. .. 50 Fig. 11 Simplified Bouguer Anomaly Kap .. ' 52' Fig. 12 Geological 1'ap of the Panafrican Orogen 54 Fig. 13 Concessions held by Uranerzbergbau-GmbH (TJEB) .. .. 67 Fig. 14 Past Exploration in Ghana .. .. 69 Fig. 15 Radioactive Anomalies and Uranium Occurrences of Ghana .. .. 74 Fig. 16 Amoanda Pegmatite .. .. 81 Pig. 17 Uranium Occurrences and Deposits in T,-,restern Gondwana .. .. 83 Fig. 18 Drill Eole Locations in the .Volta Basin 92 Fig. 19 Areas Recommended for the Large Scale Exploration Programme .. .. 104 T7T LIST 0"? T.'-BIS?. Page Table 1 ELneral Production of Ghana in 1977 •. 13 Table 2 Details of Operations of GCS Ltd. from 1977/78 to 1980/80. UnsnciBl Years .. .. 16 Table 3 Diamond Scports of Ghana .. .. 16 Table 4 Gold Production of Ghana .. •. I7 Table 5 Manganese Production of the ITsuta Kine •. •• 18 Table 6 Stratigraphy of the Lower BirinrLan .. 3O Table 7 Stratigraphy of the Upper Eirindan .. 31 Table 8 Stratigraphy of the Tarkwaian System .. 36 Table 9 Stratigraphy of the Togo Series ,. 41 Table 10 Stratigraphy of the Buem Formation .. 42 Table 11 Stratigraphy of the Voltaian System after JTJHK3R and HIRST (1946) •• •• 44 Table 12 Stratigraphy of the Yoltaian Basin after BOJXO (1964) •• .. 45 Table 13 Voltaian Stratigraphy, Facies and Correlations after BASR (1977) •• 48 Table 14 Stratigraphy of the Accra Series .. 55 Table 15 Stratigraphy of the Sekondi Series .. 56 Table 16 Stratigraphy of the Keta Basin .. 57 Table 17 Stratigraphy of the Tano Basin .. 59 Table .18 Metallogeny of Ghana .. .. 62 Table 19 Radioactive Anomalies in Ghana. .. 79 Table 20 Uranium Occurrences and Deposits in Selected Geotectonic Units of Uesterr. Gondwana .* 84 Table 21 Sodium Anomalies in the Cape Coast Granite 97 Table 22 Speculative Uranium Resources of Ghana .. 102 Table 23 Costs Estimate for Recommended Programmes .. .. 108 I. Indexes of Geological and Topographical Maps II. Minerals Act and Adrsinistrction of Lands Act III. Ordinances Regulating Uranium Prospecting IV. Investment Code V. Geological Log of SHELL Prenuase - 1 "ell VI. Possible Input of the Gravimetric Kap Interpretation to the Definition of Prospective Areas. • • . - 1 - ' B E ' R " C T ' 2he Republic cf Ghana has no claimed uranium Resources in the categories Reasonably Assured and Estimated Additional. The only occurrences known are within pegmatites and are of no economic importance. The IUIS? Orientation Hiase I'issior. to Ghana estimates that the Speculative Resources of the country fall "between 15,000 and 40,000 tonnes uranium. Past uranium exploration in Ghana by the United Kingdom Geological Survey, Hunting Survey Ltd., Uranerzbergbau-GmbK, the IAEA and ihe Ghana Atomic Energy Commission in association with the Ghana Geological Survey did not show positive results. The total expenditure of all previous exploration amounts to appro- ximately US #5,500,000. Ghana, with a population of 14 j^Lllions and a surface of 240,000 square kilometers has, by African standards, a well deve- loped infrastracture. After cocoa, the gold, diamond, manganese and bauxite mining industry is the second most important export earner of -Sie country. Geologically, almost 9C£ of Ghana lies within the "est African Shield and the remaining part within the Dahomeyan ?anafrican Mobile Belt. That part underlain by the shield was formed by the Eburnean orogenic cycle which started with the eugeosynclinal flysch and greenstones of the Birimian Sj'stem, culminated with the intrusions of the syntectonic and posttectonic granites and terminated with the molasse of the Tarlzwaian System. All economic mineral deposits occur within this geotectonic unit. - 2 - The Panafrican orcger.ic cycle started vi-th the nyogecsynclinal and flysch sediments of the Sshomeyan Astern, ?c~o 3erics and Buem Formation, culminated ir. the ranafricar. thermotectonic event and terminated -rith the -mclc^e of the Ycltsian basin. This gectectcnic unit is free cf mineral deposits in Ghana. However, its extensions to the ITorth, in Algeria, and to the South in Brazil, contain major uranium deposits iriLth resources exceeding 200,000- tonnes uranium oxi&e. Hhe IURE? Orientation Phase "ission to Ghana believes that the Panafrican Mobile 3elt has the highest uranium' potential cf all geological units of the country. In Ghana the Dahomeyan System, central part of ^he Mobile Belt, covers an area of approximately 10,000 square kilometers. It is considered as the priority number one target. Trie deposits sought here are of the vein type, possibly associated with sodium metasomatism as it is the case in Brazil. The Obosum beds are the priority number two target. They underlie an area of 55»000 square kilometers and represent the molasse of the Fanafrican orogen._ The deposits expected here are of the sandstone type as kno*.rn from the Colorado Plateau of the U.S.A. and many other parts of the world. A three years exploration programme is recommended for a total cost of US #5>000,000. The Ghana Atomic 3nergy Commission and the Ghana Geological Survey provide a basic infrastructure for uranium exploration. However, they lack sufficient funds and uranium exploration expertise to carry out the large scale programme recommended in this report. It is therefore proposed that C-hana seeks either bi-cr multilateral financial and technical aid or joint ventures'.-a th foreign companies. Any future uranium development in Ghana should be embedded in a v;ell defined national uranium policy. It is recommended that such a policy be draw, up by the Ghanaian authorities. - 3 - B. BTTRODUCTIOI'T 1. Terms of Reference She basic objective of the International Uranium Resources Evaluation Project (IUREP) 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'1, Bierefore the scope of the ITTEBF Orientation Hiase Mission to Ghana was - . to review the data on past exploration programmes in Ghana, - to develop a better understanding of the uranium potential of the country* - to make an estimate of the speculative resources of the country. - to delineate areas favourable for the discovery of these uranium resources. to make recommendations on -the appropriate exploration methods and techniques to verify the resources in the delineated areas.