UNDISCOVERED URANIUM RESOURCES

IN GHANA

1

Samuel B. Dampare1,2, Thomas K. Adu3, Akwasi B.

Asumadu-Sakyi2,

1Graduate School of Nuclear and Allied Sciences, University of Ghana-

Atomic, P.O. Box LG 58, Legon-Accra, Ghana

2National Nuclear Research Institute, Ghana Atomic Energy

Commission,

P.O. Box LG 80, Legon-Accra, Ghana

3Ghana Geological Survey Department, Accra, Ghana

IAEA WORKSHOP ON ‘‘APPLICATION OF UNITED NATIONS FRAMEWORK CLASSIFICATION-2009

(UNFC-2009) FOR URANIUM RESOURCES’’JOHANNESBURG, SOUTHAFRICA, 10 – 14 NOVEMBER, 2014

INTRODUTION

2

INTRODUCTION CONT’D

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Ghana is endowed with mineral resources

Major mineral resources: gold, diamonds, manganese, bauxite and

oil

Gold is predominant mineral accounting for about 80 % of all

mineral revenues.

Unexploited or least exploited deposits: iron ore, limestone, brown clays, kaolin, mica, columbite-tantalite, feldspar, silica sand and quartz.

Minor deposits: ilmenite, magnetite and rutile.

Ghana discovered about one (1) billion barrels of offshore oil in 2007.

Insufficient energy to support the growing population and industrial activities

Ghana is, therefore, embarking on nuclear power project to introduce nuclear energy into the country’s energy mix

The need to explore for radioactive minerals cannot be overemphasized

GEOLOGICAL SETTING

4

Adopted after Attoh et al., 2006

5

HISTORY OF EXPLORATION FOR RADIOACTIVE

MINERALS IN GHANA

DATE ACTIVITY INVESTIGATORS/FUNDED AGENCIES

FINDINGS AND REMARKS

1952 First attempt of radioactive

minerals prospecting

D. Ostle, P.H. Hale plus a

Geologist from Gold Coast

Geological Survey Dept.

In most rocks, thorium content was about 0.1

% and uranium content was not remarkable

1953-

76

Geochemical survey,

Radiometric surveys,

Individuals., Gold Coast

Geological Survey Dept.,

Uranerzbergbau (GmbH)

International Atomic Energy

Agency

• Uranium-bearing pegmatites in the Cape

Coast area were of no economic

significance.

• Low possibility of discovering large and

easily obtainable uranium deposit in

crystalline areas of Ghana.

• The Tarkwa complex unfavourable for

development of uranium deposits.

• Prospecting efforts should be focused on

sedimentary formations of the Voltaian, in

an attempt to discover a sandstone-type

uranium deposit.

• The syenites contained small quantities of

thorium and uranium minerals (allanite

and pyrochlore) with extremely low

grade.

• Areas of higher radioactivity were

situated on top of syenites and nepheline-

syenites of the Dahomeyan.

HISTORY OF EXPLORATION FOR

RADIOACTIVE MINERALS IN GHANA CONT’D

6

DATE ACTIVITY INVESTIGATORS/FUNDED AGENCIES

FINDINGS AND REMARKS

1982

Evaluation of

potential

deposits in

Ghana

International Uranium

Resources Project

(IUREP)

• Dahomeyan Formation– major uranium target due to its

occurrence in the Pan African-Brazilian mobile belt

• Voltaian Supergroup – similar age to the Taoudeni Basin

in Guinea and has the potential to host uranium deposits

• Eburnean Granites – host known deposits and may host

further similar types.

• Tarkwaian Group – the conglomerates have the potential

to host uranium similar to the palaeoplacer deposits in

South Africa

• Togo and Buem Structural Units – no potential

• Coastal basins – low potential

• Palaeozoic Accraian and Sekondian Series – low potential

• Cretaceous and Tertiary basins – low potential

• Birimian Formation – low potential

RECENT URANIUM EXPLORATION-RELATED

ACTIVITIES

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DATE ACTIVITY INVESTIGATORS/FUNDED AGENCIES

FINDINGS AND REMARKS

2008 Uranium content study

at Biakpa, Volta Region

using Track Etch

technique

Osborne C. Oppon and Akwasi

B. Asumadu-Sakyi of Ghana

Atomic Energy Commission

Mean percentage concentration of uranium in

rocks was 0.018 %.

2010 Airborne Geophysical

Surveys of the Voltaian

and Keta Basins

EU-funded Mining Sector

Support Programme (MSSP)

Anomalous areas for uranium potential were

identified.

2011-

2012

Follow-ups on Airborne

geophysical Anomalies

of the Voltaian Basin

Geological Survey

Department, Ghana

All the rocks analyzed had uranium

concentration below 10 ppm (< 10 ppm)

8

2

4 3 1

POTENTIAL HOST ROCK TYPES FOR URANIUM DEPOSITS IN

GHANA (INFERENCE FROM IUREP REPORT, 1982)

9 GAMMA-RAY SPECTROMETRY DATA) MAGNETIC FIELD ANOMALY

AIRBORNE GEOPHYSISICAL SURVEYOF THE

VOLTAIAN AND KETA BASINS

10 GEOTEM AIRBORNE ELECTROMAGNETIC

SURVEY

AIRBORNE GEOPHYSISICAL SURVEYOF THE

VOLTAIAN AND KETA BASINS CONT’D

FREE-AIR GRAVITY FIELD

FOLLOW –UPS ON AIRBONE ANOMALIES

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SAMPLE CODING

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THE WAY FORWARD/FUTURE PLANS

• Geological Survey Department (GSD) is currently carrying out

ground follow-ups on the anomalies identified by airborne

geophysical surveys

• Anomalous areas of uranium concentration need to be well defined

• Prospectivity modelling approach, proposed by the British Geogical

Survey, is being considered for the sandstone-hosted uranium in the

Voltaian Basin

• Three areas have been targeted in the Voltaian Basin:

northern, western area and southern parts

• Strengthening collaboration among GSD, Ghana Atomic Energy

Commission and University of Ghana to continue with the uranium

exploration activities

• Have a national project on uranium exploration

• Step up public education on uranium and nuclear power issues

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CHALLENGES AND NEEDS

• Inadequate funds for ground follow-ups on anomalous areas

• Lack of equipment for effective ground follow-ups

Continued support from the IAEA would be required in the following areas:

TC Project on Uranium Exploration in Ghana

Expert Advice/Mission

Further training course in uranium exploration techniques and methods

Equipment to support the GSD/GAEC/UG exploration team

Image Analyzers for Nuclear Track Counting

Track Etch Detectors

Spark Counter Spectroscopy Amplifiers

Broadband Gamma-Ray Scintillometers

Portable Gamma-Ray Spectrometers D25A-400A

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CONCLUSIONS

• Although Uranium prospecting in Ghana started in the early days, it

did not yield any economic viable deposits of the mineral

• Recent studies have shown that Ghana stands a high chance of

striking Uranium deposit

• Airborne surveys carried out to cover the entire country had

identified some anomalous potential areas for radioactive mineral

deposits, particularly in the Voltaian and Keta Basins

• Ground investigations are being carried out by the Geological

Survey Department together with Ghana Atomic Energy

Commission

• Preliminary geochemical results from the Voltaian Basins are not

encouraging therefore further studies are to be carried out

• Geochemical studies are to be conducted at potential areas such as

Dahomeyan formation

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APPLICATION OF UNFC-2009 TO EXPLORATION

PROJECT OF GHANA

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Deposit

/

Project

Investigator UNFC-

2009

Class

UNFC

-2009

Sub-

Class

UNFC-2009

Categories

Remarks

E F G

Voltaian

Basin

Explorat

-ion

Ghana Geological Survey Department

Exploration project

None 3.2 3 4 Early

Exploration

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THANK YOU