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Table of Contents 
ABSTRACT ................................................................................................................................................... i 
DEDICATION .............................................................................................................................................. ii 
ACKNOWLEDGEMENT ........................................................................................................................... iii 
QUOTES ........................................................................................................................................................ iv 
CHAPTER ONE ................................................................................................................................. 1 
INTRODUCTION .............................................................................................................................. 1 
1.2 Problem Statement .................................................................................................................... 6 
1.3 Aim ........................................................................................................................................... 6 
1.4 Objectives ................................................................................................................................. 6 
1.5 Importance of Research ............................................................................................................ 6 
1.6 Scope of Work .......................................................................................................................... 7 
CHAPTER TWO ................................................................................................................................ 8 
COPPER OCCURRENCES AND DEPOSIT TYPES IN ZAMBIA ................................................. 8 
2.1 Introduction .............................................................................................................................. 8 
2.2 Copper Occurrences in Zambia ................................................................................................. 8 
2.3 Copper Deposit Type ................................................................................................................ 9 
2.3.1 The Central African Copperbelt ............................................................................................ 9 
2.3.2 Distribution of Mineralisation in the Zambian Copperbelt (Kafue Anticline) .................... 12 
2.3.3 Styles of Minerilisation in the Deposit of the Zambian Copperbelt.................................... 13 
2.4 Styles of Minerilisation in Deposits of the Domes Region ..................................................... 15 
2.5 Iron Oxide-Copper-Gold (IOCG) Deposits in the Greater Lufilian Arc ................................ 15 
CHAPTER THREE .......................................................................................................................... 17 
METHODOLOGY AND CHARACTERISTIC OF DEPOSITS .................................................... 17 
3.1 Introduction ............................................................................................................................. 17 
3.2 Methodology Flow Chart ........................................................................................................ 17 
3.3 Selection and Characteristization Copper Deposits in Zambia ............................................... 18 
3.4 The Kitumba Deposit .............................................................................................................. 19 
3.4.1 Geographic Location ........................................................................................................... 19 
3.4.2 Tectonic Setting .................................................................................................................. 19 
3.4.3 Geology of Kitumba Deposit .............................................................................................. 19 
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3.5 The Konkola Deep Deposit ................................................................................................. 21 
3.5.1 Geographic Location ........................................................................................................... 21 
3.5.2 Tectonic Setting .................................................................................................................. 22 
3.5.3 Geology of Konkola Deep Deposit ..................................................................................... 22 
3.6 The Chambishi Main Deposit ................................................................................................ 24 
3.6.1 Geographic Location ........................................................................................................... 24 
3.6.2 Tectonic Setting .................................................................................................................. 24 
3.6.3 Geology of Chambishi Main Deposit ................................................................................. 24 
3.7 The Chimiwungo Deposit ....................................................................................................... 26 
3.7.1 Geographic location ............................................................................................................ 26 
3.7.2 Tectonic Setting .................................................................................................................. 26 
3.7.3 Geology of Chimiwungo Deposit ....................................................................................... 26 
3.8 The Kansanshi Deposit ........................................................................................................... 28 
3.8.1 Geographic Location ........................................................................................................... 28 
3.7.2 Tectonic Setting: ................................................................................................................. 28 
3.8.3 Geology of Kansanshi Deposit............................................................................................ 28 
3.9 Geophysical Forward Modelling ............................................................................................ 30 
CHAPTER .................................................................................................................................................. 31 
FOUR MODELLING ................................................................................................................................. 31 
4.1 Introduction ............................................................................................................................ 31 
4.2 Gravity and Magnetic Models for Kitumba Deposit ............................................................... 34 
4.3 Gravity and Magnetic Models for Konkola Deep Deposit ..................................................... 37 
4.4 Gravity and Magnetic Models for Chambishi Main Deposit .................................................. 40 
4.4 Gravity and Magnetic Models for Chimiwungo Deposit ........................................................ 43 
4.6 Gravity and Magnetic Models for Kansanshi Deposit ............................................................ 46 
CHAPTER FIVE ........................................................................................................................................ 50 
DATA ANALYSIS AND DISCUSSION ...................................................................................................50 
5.1 Introduction ............................................................................................................................ 50 
5.2 The Kitumba Deposit ............................................................................................................. 50 
5.3 The Konkola Deep Deposit ..................................................................................................... 51 
5.3 The Chambishi Main Deposit ................................................................................................. 53 
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5.4 The Chimiwungo Deposit ....................................................................................................... 55 
5.5 The Kansanshi Deposit ........................................................................................................... 57 
`CHAPTER SIX.......................................................................................................................................... 59 
CONCLUSIONS AND RECOMMENDATIONS ..................................................................................... 59 
6.1 Conclusions ............................................................................................................................. 59 
6.2 Recommendations ................................................................................................................... 60 
REFERENCES ........................................................................................................................................... 61 
Appendix I .................................................................................................................................................. 63 
Appendix II ................................................................................................................................................. 64 
 
List of Figures 
Figure 1: (a) Long run historical copper production in (b) Short run historical copper production ............. 1 
Figure 2: Copper production Histogram for the World and Zambia between 2001 and 2014. Data Source: 
US Geological Survey, Mineral Commodity Summaries 2012; US Geological Survey Mineral 
Information — Zambia ................................................................................................................................. 2 
Figure 3: The national contributions of mining to the Zambian economy (after Oxford Policy 
Management (OPM), 2012). ......................................................................................................................... 3 
Figure 4: Copper Occurrence distribution in Zambia. ( after Geological Survey Department (GSD), 1998)
 ...................................................................................................................................................................... 8 
Figure 5: Tectonic Setting of Zambian, the Lufilian Arc and its structural zones (after Binda and Poranda 
1995). ............................................................................................................................................................ 9 
Figure 6: Zambian Copperbelt deposits distribution along the Kafue Anticline (modified from Selley et 
al., 2005). .................................................................................................................................................... 12 
Figure 7: Generalized stratigraphic section through the Copperbelt deposits (modified from Selley et al., 
2005). .......................................................................................................................................................... 13 
Figure 8: Methodology flow chart illustrating in summary the methodology ............................................ 17 
Figure 9: (a) Location of the selected deposits. (b) Tectonic controls of the selected deposits. ................ 18 
Figure 10: Geological Map of Kitumba Deposit (after Intrepid Mines Limited, 2014). ............................ 19 
Figure 11: The geological section of Kitumba deposit and its geophysical properties (after Intrepid Mines 
Limited, 2014)............................................................................................................................................. 21 
Figure 12: Geological map of Konkola Deep deposit and the surrounding area (after Porter 
GeoConultancy, 2014). ............................................................................................................................... 22 
Figure 13: The geological section through A-B of Konkola Deep deposit (after Porter GeoConultancy, 
2014). .......................................................................................................................................................... 23 
Figure 14: The geological map of Chambishi deposits (modified after Croaker, 2011). ........................... 25 
Figure 15: Representative cross section through the Chambishi Main deposit(modified after Croaker, 
2011). .......................................................................................................................................................... 25 
Figure 16: Block view and Cross section of the Chimiwungo deposit (after Golder, 2003). ..................... 27 
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Figure 17: the geological map of Kansanshi Deposit and a representative cross section across it. ............ 29 
Figure 18: Creating a project and setting the parameters. ........................................................................... 31 
Figure 19: Creating Synthetic grid. ............................................................................................................. 32 
Figure 20: Creating Synthetic lines. ............................................................................................................ 32 
Figure 21: Specification of modelling type and computation of the region gravity and magnetics. .......... 33 
Figure 22: Selecting the line to model. ....................................................................................................... 33 
Figure 23: Generating gravity and magnetic geophysical responses. ......................................................... 34 
Figure 24: Block model of Kitumba deposit. .............................................................................................. 34 
Figure 25: Block Model of Konkola deep deposit. ..................................................................................... 37 
Figure 26: Gravity and magnetic properties of Konkola deep deposit section. .......................................... 38 
Figure 27: Block model for Chambishi deposit. ......................................................................................... 41 
Figure 28: Block Model for Chimiwungo deposit. ..................................................................................... 43 
Figure 29: Block Model of Kansanshi deposit. ........................................................................................... 47 
Figure 30: Gravity (blue line) and magnetic (red line) profile for Kitumba Deposit at a depth of 60m. .... 50 
Figure 31: Plot of Change in depth with respect to the Magnetic and Gravity response for Kitumba 
deposit. ........................................................................................................................................................ 51 
Figure 32: Gravity (blue line) and magnetic (red line) profile for Konkola Deep Deposit at a depth of 
60m. ............................................................................................................................................................52 
Figure 33: Plot of Change in depth with respect to the Magnetic and Gravity response for Konkola Deep 
deposit. ........................................................................................................................................................ 53 
Figure 34: Gravity (blue line) and magnetic (red line) profile for Chambishi at a depth of 0m. ................ 54 
Figure 35: Plot of Change in depth with respect to the Magnetic and Gravity response for Chambishi 
deposit. ........................................................................................................................................................ 54 
Figure 36: Gravity (blue line) and Magnetic (red line) profile for Chimiwungo deposit at a depth of 100m.
 .................................................................................................................................................................... 55 
Figure 37: Plot of Change in depth with respect to the Magnetic and Gravity response for Chimiwungo 
deposit. ........................................................................................................................................................ 56 
Figure 38: Gravity (blue line) and Magnetic (red line) profile for Kansanshi Deposit at a depth of 80m. . 57 
Figure 39: Plot of Change in depth with respect to the Magnetic and Gravity response for Kansanshi 
Deposit. ....................................................................................................................................................... 58 
 
List of Tables 
Table 1: Zambia‘s mining taxes as a share of GDP and total taxes collected for 2008 and 2012 (Zambia 
Revenue Authority (ZRA), 2013). ................................................................................................................ 4 
Table 2: Some IOCG deposit type of the Greater Lufilian Arc in Zambia (after Lobo-Guerrero, 2012). .. 16 
Table 3: Gravity and Magnetic properties of the Kitumba Deposit (after Intrepid Mines Limited, 2014). 21 
Table 4: Gravity and Magnetic properties of the Konkola Deep deposit (Telford el at, 1994). ................. 23 
Table 5: Gravity and magnetic properties of the Chambishi Main deposit (Telford el at, 1994). .............. 26 
Table 6: Gravity and Magnetic properties of Chimiwungo deposit (Telford el at, 1994). ......................... 27 
Table 7: Gravity and Magnetic properties of Kansanshi Deposit (Telford el at, 1994). ............................. 29 
Table 8: Depth relationship with Maximum Gravity and Magnetic Susceptibility for Kitumba Deposit .. 51 
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Table 9: Depth relationship with Maximum Gravity and Magnetic Susceptibility for Konkola Deep 
deposit ......................................................................................................................................................... 52 
Table 10: Depth relationship with Maximum Gravity and Magnetic Susceptibility for Chambishi Main 
deposit ......................................................................................................................................................... 54 
Table 11: Depth relationship of Maximum Gravity and Magnetic Susceptibility for Chimiwungo deposit
 .................................................................................................................................................................... 56 
Table 12: Depth relationship of Maximum Gravity and Magnetic Susceptibility for Kansanshi Deposit . 57 
 
Gravity and Magnetic Simulation Models for the Deposits 
 
Kitumba Deposit 
Scenario 1 at 60m depth .............................................................................................................................. 35 
Scenario 2 at 168m depth ............................................................................................................................ 35 
Scenario 3 at 700m depth ............................................................................................................................ 36 
Scenario 4 at 2000m depth .......................................................................................................................... 36 
Scenario 5 at 5000m depth .......................................................................................................................... 37 
Konkola Deep Deposit 
Scenario 1 at 100m depth ............................................................................................................................ 38 
Scenario 2 at 170m depth ............................................................................................................................ 39 
Scenario 3 at 270m depth ............................................................................................................................ 39 
Scenario 4 at 670m depth ............................................................................................................................ 40 
Scenario 5 at 1670m depth .......................................................................................................................... 40 
Chambish Deposit 
Scenario 1 at 0m depth ................................................................................................................................ 41 
Scenario 2 at 50m depth .............................................................................................................................. 42 
Scenario 3 at 200m depth ........................................................................................................................... 42 
Scenario 4 at 500m depth ............................................................................................................................ 43 
Chimiwungo Deposit 
Scenario 1 at 50m depth .............................................................................................................................. 44 
Scenario 2 at 200m depth ............................................................................................................................ 44 
Scenario 3 at 400m depth ............................................................................................................................ 45 
Scenario 4 at 750m depth ............................................................................................................................ 45 
Scenario 5 at 1400m depth .......................................................................................................................... 46 
Scenario 6 at 5600m depth .......................................................................................................................... 46 
Kansanshi Deposit 
Scenario 1at 80m depth ............................................................................................................................... 47 
Scenario 2 at 480m depth ............................................................................................................................ 48 
Scenario 3 at 880m depth ............................................................................................................................ 48 
Scenario 4 at 1280m depth .......................................................................................................................... 49 
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ABSTRACT 
Copper is nonrenewable resource which is and has been an essential material to man since pre-
historic times. This commodity has seen a somewhat positive gradient in demand from the time 
of its pre-historical use to date. Zambia is a major contributed to the production of Copper and 
it‘s the 2
nd
 largest African producingcountry. Now due to the increased demand of Copper 
which is mostly as a result of increased urbanization and industrialization of both developed 
economies like the US, UK, Germany Russia and also immerging economies like China, India, 
Brazil and South Africa, Exploration of this commodity is inevitable. 
 
Mineral exploration is a huge capital, risky and non-cash flow venture which incurs huge costs 
mainly at drilling stage but with the advancement in geophysical softwares the risk is reduced. 
This is because geophysical data allows for 2D and 3D modelling, thereby giving the subsurface 
features and this aids in determining the right orientation for drilling that will intercept the body. 
Forward modelling the process of calculating a response (e.g. a gravity measurement) from a 
given earth model whilst inversion modelling is the process that seeks to produce a 3D 
distribution of physical rock properties (e.g. density) that should meet an observation measured 
in the field. Hence by using the data available on the known deposits in Zambia in terms of their 
geology, stratigraphy and physical properties (density and magnetic susceptibility), Forward 
modeling was done to produce synthetic gravity and magnetic models at different depth so as to 
aid in the exploration of greenfield Copper. Forward modeling was done on the following 
deposits Kitumba, Konkola Deep, Chambishi, Chimiwungo and Kanshashi deposit. Selection of 
deposits was based on mainly their type of Copper deposits. 
 
The presence of sedimentary rocks except quartzites in the deposit modeled resulted in very low 
magnetic anomaly, this is likely because these rocks have relatively low magnetic susceptibility, 
sedimentary rocks also exhibits low gravity anomalies, sometimes negative depending on the set 
background values for the density while The presence of basement rocks in a body result in high 
magnetic and gravity anomaly, this is likely because these rocks have relatively high magnetic 
susceptibility and densities. 
 
 Generally Strata-bound sedimentary copper deposits have a limiting depth of approximately 
450m and 300m for gravity and magnetic response respectively. Therefore for a similar deposit 
in Western Province, magnetic and gravity methods will not be effective because the cover is 
over 600m in same areas. IOCG and Strata-bound Disseminated Copper deposits produce good 
gravity and magnetic response and the limiting depth is approximately 1500m and 1700m 
respectively. Vein-hosted copper deposit produces a good magnetic response with effective 
depth of approximately to 800m. Hence magnetic methods can be applied for exploration in 
Western Province. 
 
 
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DEDICATION 
This thesis is dedicated to my Parents, Mr and Mrs Banda: for their support and belief they have 
always given me. To my brothers and Sisters (Saulosi, Candy, Mpando, Mapalo, Muchemwa and 
Mwila): success is always a guarantee when you put your very best. Pamela for her love and 
consistent push in making sure I excel during my stay at University of Zambia. My Good 
friends: Albert and Kelvin, you have been great company and last but not the least: Chi-alpha 
Christian Fellowship for being family to me and a hub for spiritual growth. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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ACKNOWLEDGEMENT 
I would like to express my sincere gratitude to the following people and company: 
Vale Zambia Limited for coming up with this project and facilitating the required resources for 
me to carry out this project. 
 
Special thanks go to my supervisor: Dr. O.N. Sikazwe for making that sound interpretation and 
writing of the report writing is archived. You always gave me a challenge to think out of the box. 
 
Mr S Nkemba for the advice and help he rendered at during consultations, it surely paid off. 
 
The Hold of Department (HOD) Mr S Musiwa and all the lectures in the geology, thank you for 
sharing your experience, knowledge and wisdom with me. 
 
Mr P Zimba thank you for your warm heart and assistance in printing this report. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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QUOTES 
 
Psalm 46:10 
―Be Still, and Know that I am God.‖ 
 
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CHAPTER ONE 
INTRODUCTION 
1.0 Background 
 
Copper is and has been an essential material to man since pre-historic times. In fact, one of the 
major "ages" or stages of human history is named for a copper alloy, bronze. Copper and its 
many alloys have played an important role in many civilizations, from the ancient Egyptians, 
Romans to modern day cultures around the world. The price of copper has increased 
substantially with the highest record being nearly US $10000 per tonne in the year 2009 to 2011 
(figure 1). Regardless of the overall increase in copper demand and prices in the long run, copper 
demand and prices take a twist in short run and thereby making the mining industry very 
uncertain. Currently the prices of copper have fallen to as low as US$ 6040 per tonne making 
some mines operate below the break-even point and hence leading to closure or care and 
maintenance. The world currently consumes more than 26 million tonnes of copper on an annual 
basis and as of the year 2013 approximately 18 million tonnes of copper was produced from 
mining (Appendix I) while the remaining 8 million tonnes was supplied from recycling of scrap. 
This huge consumption is because of the increased urbanization and industrialization of both 
developed economies like the US, UK, Germany Russia and also immerging economies like 
China, India, Brazil and South Africa. China alone is currently consuming about 40% of the total 
world copper consumption. 
 
Figure 1: (a) Long run historical copper production in (b) Short run historical copper production 
 
Zambia is a beneficially to the rise in copper demand and prices because the mining industry is 
the major single contributor to its Gross Domestic Product (GDP). Commercial-scale mining has 
taken place in Zambia for around 100 years, and is confidently expected to continue for many 
years to come. Industry has gone from private ownership in the early years, through a period of 
nationalization, and most recently back into private hands. As a result of the recent privatization, 
in excess of US$8 billion has been invested by the new owners. Some of this has been necessary 
to refurbish and modernize the infrastructure and operations of the ‗legacy‘ mines on the 
(a) (b) 
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Copperbelt, but most has been invested in new or expanded operations. This has been most 
noticeable in the Northwest Province, dubbed ‗the New Copperbelt‘. Resulting from this 
investment, annual finished production has risen from a low of 257,000 metric tonnes per 
annum to over 700,000 metric tonnes in 2013 (Figure 2). The total is confidently predicted to rise 
to over 1 million metric tonnes in the next couple of years and towards 1.5 million metric tonnes 
within 5–10 years. Zambia is the second largest copper producer in Africa from Democratic 
Republic of Congo (DRC) with copper production of 730,000 and 1.1 million tonnes 
respectively. 
 
 
Figure 2: Copper production Histogram for the World and Zambia between 2001 and 2014. Data 
Source: US Geological Survey, Mineral CommoditySummaries 2012; US Geological Survey 
Mineral Information — Zambia 
 
Zambia broadly conforms to the inverted pyramid pattern of macroeconomic contributions with 
very high contributions in some macro areas (notably exports and investment) but progressively 
lower contributions in other areas such as government revenues, GDP and employment (Figure 
3). Since the early 2000s, mining investment has boomed with over US$10 billion in Foreign 
Direct Investment (FDI) since privatization. FDI flows have been dominated by mining: in 2011, 
new FDI into mining accounted for 86.2 per cent of total FDI. Whilst Copper mining accounts 
for over 80 per cent of export earnings. This is a high share even in comparison to other mineral-
driven countries. Many decades of official statements of intent and policies intended to diversify 
the economy have met with limited success. Government revenues collected from mining have 
increased sharply in recent years to over 30 per cent of total tax revenues, according to official 
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Zambia Revenue Authority (ZRA) data. Government revenues from mining were low (around 16 
% of total tax revenues) until around 2008 but subsequently increased sharply (Table 1). 
 
In 2011, Zambia‘s GDP stood at US$18.4 billion in terms of market exchange rates, and 
US$21.93 billion in terms of purchasing power parity. The mining sector contribution to GDP is 
projected to grow to 20% over the medium term, to reach $1.35 billion by the end of 2015. This 
increase will position Zambia among the world‘s top five copper producers. The employment 
contribution of mining is the smallest of the direct macro contributions but still large in absolute 
terms. The absolute numbers of jobs in mining have increased substantially in response to higher 
levels of investment and production. The preliminary results of the national Labour Force Survey 
for 2012 (Central Statistical Office, 2013a) show total formal employment in mining in 2012 of 
over 90,000. This represents about 1.7 % of the labour force, 8.3 % of total formal sector jobs 
and around 25 % of total private sector formal jobs in 2012. The indirect and induced jobs 
associated with mining are significant contributors to local welfare. Multiplier calculations 
indicate that ―indirect‖ job creation (via spending on local supplies) and ―induced‖ employment 
(through mining employees spending their relatively high average incomes) together increase the 
total employment attributable to mining by a factor of between two and four; that is, for each 
direct job with a mining company or an on-site contractor, two to four additional jobs are created 
elsewhere in the economy (International Council of Mining and Metals, 2014). 
 
 
Figure 3: The national contributions of mining to the Zambian economy (after Oxford Policy 
Management (OPM), 2012). 
 
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Table 1: Zambia‘s mining taxes as a share of GDP and total taxes collected for 2008 and 2012 
(Zambia Revenue Authority (ZRA), 2013). 
Year GDP in 
ZMW 
million 
Total taxes 
collected in 
ZMW million 
Mining taxes 
collected in ZMW 
million 
Mining taxes (%GDP) Mining taxes (% 
total taxes) 
2008 54,839 9,670 1541 2.8% 16% 
2012 11,049 20,723 6,619 5.9% 3 2% 
Note that the reported currency is in rebased format. 
 
From the above statistics it‘s clear that the backbone of the Zambia‘s economy is the mining 
industry. Hence to continue enjoying the contribution of the mining industry to the economy of 
Zambia, it‘s inevitable that mineral exploration should be the first priority because most of the 
deposits that where discovered in the 1930‘s in the Copperbelt are nearly depleted or depleted. 
Exploration is a very expensive, risky and noncash flow venture for companies but the advances 
in technology have seen enormous attempts to minimize the risk of exploration process. 
 
Geophysical applications in exploration are currently dynamic and advancements in software‘s 
have reduced the risk of exploration, thereby increasing the level of confidence in the process of 
exploration. That is, the use of geophysical inversion and forward modelling in mineral 
exploration has led to reduced risk in exploration. The forward modelling method is based on 
geological and geophysical intuition. The method allows construction of an initial model for the 
source body and then computes the model's magnetic effect that is to be compared with the 
observed anomaly (Shin et al., 2006). Forward modelling is the process of calculating a response 
(e.g. a gravity field) from a given earth model (e.g. a density distribution) whilst inversion 
modelling is the process that seeks to produce a 3D distribution of physical rock properties (e.g. 
density) that should meet an observation measured in the field (e.g. a gravity response). 
 
Developments in instrumentation, data collection, computer performance, and visualization have 
been catalysts for significant advances in modelling and inversion of geophysical data. Forward 
modelling, which is fundamental to intuitive geological understanding and practical inversion 
methods, has progressed from representations using simple 3D models to whole earth models 
using voxels and discrete surfaces. Inversion has achieved widespread acceptance as a valid 
interpretation tool and major progress has been made by integrating geological models as 
constraints for both voxel and multi-body parametric methods. As a consequence, potential field, 
IP and electromagnetic inversion methods have become an essential part of most mineral 
exploration programs. 
 
Until the 1960s most deposits were discovered by prospecting, or looking for clues on the 
surface with the help of outcropping geology. But geophysical techniques are increasingly taking 
the role of the prospector as exploration moves deeper into the subsurface. For the fact that most 
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surficial deposits have been discovered and are being exploited, the risk of exploration is high. 
The use of conventional geological and geochemical techniques on deep seated deposit is 
increasingly becoming less effective. Conventional geological and geochemical exploration 
techniques in western province of Zambia have proved to be ineffective. This is because of a 
thick sediment pile (Kalahari sands) which is about 600m thick in some areas. The Kalahari 
sands are believed to overlie an older Katanga Supergroup that is not exposed in western 
province. The Katanga Supergroup hosts the Cu-Co minerilisation in the Lower Roan Subgroup. 
With the difficulty faced in exploration in western province, forward modelling provides a plat- 
form that may make exploration possible and also reduce the risk faced in exploration by simply 
working on existing deposit models and making simulation at different depth to notice the 
response. 
 
The principle of application of any geophysical method is based on the contrast that the target 
has with the host rock. Gravity and magnetic methods are potential field methods and used for a 
wide range of applications and scales in geosciences. Traditionally, they have been used for large 
scale investigation of geologic structures. Smaller-scale applications of the gravity and magnetic 
methods are for mining exploration, environmental and engineering studies, etc. (Hinze, 1990; 
Reynolds, 1987; Sharma, 1997; Telford et al., 1996). In order to arrive at geologically 
meaningful anomaly values, the gravity or magnetic survey data are firstly processed to make 
appropriate corrections. After these steps, the surveydata is ready for interpretation or displaying 
as maps. Interpretation of potential field data is performed on either profile or map data. These 
data are most often interpreted by the use of inversion or data processing techniques. 
 
Spatial and frequency domain filtering, image processing and managing grids are essential tools 
in gravity and magnetic data interpretation. A potential field or image processing filter highlights 
different aspects of potential field data (Bhattacharyya, 1972; Clement, 1973; Gunn, 1975; Ku 
etal., 1971; Jacobsen, 1987; Telford et al., 1996; Vaclacetal., 1992). Filters can emphasize 
boundaries between geological contacts, highlight deeper or shallower sources, highlight features 
from different angles or reduce undesirable effects within the dataset. Filtering procedure can be 
undertaken in the frequency domain by means of Fourier Transform (FT) or in the spatial 
domain by convolution. Frequency domain filtering involves converting the dataset into the 
frequency domain, performing an operation on the data by applying the appropriate filter and 
then transforming the data back to the spatial domain. The most commonly used frequency 
domain filters include Reduction To Pole (RTP), pseudo gravity transformation, analytical 
continuations and derivative filters. Convolution methods involve convolving a filter impulse 
response (filter coefficients) with the dataset (Byerly, 1965). Magnetic anomalies are dependent 
on latitude. None pole at the polar region and dipolar at themed latitude. Hence the use of RTP 
filters. In addition to filtering, the main intention of gravity and magnetic data interpretation is 
calculating the potential field from the constructed model (forward-modeling).Various methods 
have been developed for different aims: simple geometries, sequence of isolated 2-Dor3-D 
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bodies or layers (Blakely, 1996; Jessel, 2001; Parker, 1972; Rasmussen and Pedersen, 1979; 
Telfordetal., 1996). 
 
1.2 Problem Statement 
 
Exploration of copper in green field areas is very risky without the application of geophysical 
techniques. 
 
1.3 Aim 
 
The aim of this project is to use the available data on known copper deposits in terms of their 
geology, stratigraphy and geophysical properties (density and magnetic susceptibility) to develop 
geophysical models to aid in green-field exploration. 
 
1.4 Objectives 
 
 To select deposits for forward modelling. 
 Compile magnetic and gravity properties of the selected deposits. 
 To develop gravity and magnetics profiles based on the geological models of selected 
deposits by using ModelVision geophysical software. 
 To simulate gravity and magnetic responses at different depth. In order to determine the 
limiting depth at which the anomaly will be visible. 
 To discuss the results, draw conclusions and write a report to be submitted as partial 
fulfillment for the award of Bachelors in Mineral Science in Geology at the University of 
Zambia. 
 
1.5 Importance of Research 
 
Exploration is a huge capital, risky and non-cash flow venture which incurs huge costs mainly at 
drilling stage. Therefore in the process of minimizing costs it is important that a subsurface 
representation model is developed before the commencement of drilling so that the orientation of 
the drill holes are designed to intersect through the anomalous body. With the advancement in 
geophysical software (e.g Encom ModelVision magnetic and gravity geophysical software) it is 
possible to develop representative subsurface model from an observed ground geophysical 
survey and thereby design the effective drilling pattern as in the case for inversion modeling. 
Forward modeling is the reverse of inversion modeling and requires computation of geophysical 
responses from an existing model. It allows for simulation of a known model at different depth 
thereby allowing to determine the limiting depth to which the signal of the model will 
completely fade out. A comparison between computed geophysical responses and observed 
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ground geophysical responses conducted in a new area helps determine the depth at which the 
model in the new area lies provided the observed ground responses are similar with the 
computed geophysical responses. If from comparison, it is determined that the model lies at 
depth of greater than 1500m a decision is influenced to cut any further exploration because the 
model will definitely be uneconomical to exploit. Hence this research, although academic, is 
important because it attempts to minimize cost in exploration by the use of forward modeling. 
 
1.6 Scope of Work 
 
The scope of this project is restricted to forward modelling of a few representative copper 
deposits. The geophysical response modelled for the existing deposits in this research is 
restricted to passive methods which are gravity and magnetics. This is because mainly of the 
limitation that comes with the software. ModelVison geophysical software only models gravity 
and magnetic data. 
 
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CHAPTER TWO 
COPPER OCCURRENCES AND DEPOSIT TYPES IN ZAMBIA 
2.1 Introduction 
 
Exploration works require that a target is first established and in this case the target is copper 
minerilasition. After which a target model should be developed in order to ease the selection 
process of the area to be explored, this process involves literature review on the type of deposits 
that are associated with the region in question and the controls of the mineralization. Hence in 
this chapter the main focus is to review the copper occurrences in Zambia and their style of 
mineralization. 
 
2.2 Copper Occurrences in Zambia 
 
The Geological Survey of Zambia, in conjunction with the British Geological Survey, carried out 
detailed soil and stream sediment geochemistry between 1998 and 2000 for almost the entire 
Zambia. Based on the extensive data set, a series of statistical tools were used to model trace and 
major element distributions in Zambia. Copper occurrences are mapped and show that they are 
concentrated in the Copperblet, Northwestern, and Central and Lusaka Provinces (Figure 4). A 
relationship can be inferred from the geological map of Zambia with regard to the geological 
controls that give rise to different types of copper deposits (Appendix II). 
 
 
Figure 4: Copper Occurrence distribution in Zambia. ( after Geological Survey Department 
(GSD), 1998) 
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2.3 Copper Deposit Type 
 
There are three major types of copper deposits in Zambia namely stratiform sediment hosted 
copper deposits, Iron Oxide Copper Gold (IOCG) deposits and vein-hosted copper deposits. 
Majority of the deposits in Zambia are stratiform copper sediment hosted type and they basically 
make up the Zambia Copperbelt, which together with the Congolese belt make up the Central 
African Copperbelt. 
 
2.3.1 The Central African Copperbelt 
 
The CACB is part of the Lufilian Arc, also known as the Katangan belt, a 700 km long and 150 
km wide thrust-fold belt, which is part of the Pan‐African mobile belt lying between the Congo 
and Kalahari Cratons (Cailteux et al., 2005). The Lufilian Arc consists of Katanga Supergroup 
meta-sedimentary rocks that host the Central African Copperbelt deposits and which 
unconformably overlie a pre-Katangan basement (Mendelsohn 1961). The copper-cobalt 
orebodies occur in the Roan Group of the Katangan Supergroup. The RoanGroup meta-
sedimentary rocks display a regional lateral variation of facies between Zambia-type and Congo-
type successions. The CACB has world class sediment‐hosted stratiform Cu‐Co deposits. 
 
The Lufilian Arc is divided in five structural zones (de Swardt and Drysdall, 1964), namely; 
Katanga High (IV), Synclinorial Belt (III), Domes Region (II), External Arcuate Fold and Thrust 
belt (I) and Foreland (V) (Figure 5). 
 
 
Figure 5: Tectonic Setting of Zambian, the Lufilian Arc and its structural zones (after Binda and 
Poranda 1995). 
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The Katanga High to the southwest, in which only the upper parts of the Katanga Supergroup 
and almost all of the outcropping granitic intrusions of the Lufilian Arc are exposed (Petters, 
1986; Selley et al., 2005). 
 
The Synclinorial Belt, where sediments are subjected to large scale folding during at least two 
deformation events, and low grade metamorphism, which reflects a change from a marginal shelf 
in the north, to a deeper basin (Cosi et al., 1992; Porada and Berhorst, 2000). 
 
The Domes Region, which includes the Zambian Copperbelt in its outer margins, represents 
thicker skinned deformation with upright folds, exposed basement domes (interpreted to 
represent culminations above thrust ramps), and upper-greenschist to upper-amphibolite facies 
metamorphism. 
 
The External Fold and Thrust Belt to the northeast, mainly in the DRC (where it hosts the 
Congolese Copperbelt), characterised by thin-skinned thrust/nappe-dominated deformation, 
absence of exposed basement, low-grade metamorphism and repetition of the Katangan 
stratigraphy. 
 
Foreland to the far northeast, an extension of the Katanga Basin within the DRC, produced 
during the second period of extension, characterised by less deformed Mwashya Subgroup and 
Nguba Group sedimentary rocks, and deposition of undeformed, late Kundelungu Group molasse 
rocks during and following the main compressive stage of the Lufilian orogeny. 
 
During the Lufilian orogeny the basin was inverted and the sedimentary layers were folded, 
thrusted and metamorphosed up to greenschist and amphibolite facies, with an increasing 
metamorphic grade from north to south (Cailteux et al., 2005). The tectonic evolution of the 
Lufilian arc and the Pan‐African belt is linked to the behavior of the Rodinia supercontinent. 
Intra‐continental rifting formed the sedimentary basin during the Rodinia break‐up, and the 
assembly of Gondwana led to the inversion and collisional deformation of the basin between the 
archean Congo and Kalahari cratons (Hanson, 2003). 
 
Although terms applied to sedimentary rocks are used to describe the rocks of the Zambian 
Copperbelt, the formations are distinctly metamorphic; in particular, the host rocks to the 
mineralization include mica schists, which may contain carbonates, talc or tremolite (Moine et al. 
1986). The metamorphic minerals observed include, biotite, sericite, scapolite, tourmaline, 
chlorite, tremolite-actinolite, epidote and apatite (Mendelsohn 1961). 
 
The Katangan supergroup is divided into three groups, namely: Roan Group, Nguba Group and 
uppermost Kundelungu Group. It is composed of varying sequences of carbonates, shales and 
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siliciclastic sediments (Cailteux et al., 2005) and the groups are separated from each other by 
diamictites, which are associated with global glacial events (Batumike,Kampunzu, & Cailteux, 
2006). The Roan Group is the oldest, overlying the basement rocks. The Nguba Group overlies 
the Roan Group. The Kundelungu Group sediments were deposited before, during and after the 
Lufilian orogeny (Cailteux et al., 2005). 
 
Roan Group 
 
The Roan Group is the lower unit of the Katanga succession and is divided into the Lower Roan 
and the Upper Roan Groups. The Roan Group unconformably overlies the Basement and 
represents the first phase of the initial uplift and rifting which resulted in the deposition of 
texturally immature proximally derived coarse conglomerates at the base. This was followed by a 
marine transgression and sedimentation of sub-arkosic sandstones, and rare siltstones deposited 
in fluvial, alluvial fan, aeolian and fan-delta environments. Shallow marine sediments which are 
a mixed carbonate platform-hypersaline lagoon evaporate environment, traditionally demarcate 
the boundary between the Lower Roan and the Upper Roan Group by the predominance of 
carbonate strata (e.g. Gray, 1932; Mendelsohn, 1961). The Upper Roan Group is characterized 
by laterally extensive, meter-scale, upward fining cycles of sandstone, siltstone, shales, dolomite, 
algal dolomite and local nodular anhydrite. 
 
Nguba Group 
 
Deposition of the Nguba Group (formerly Lower Kundelungu) commenced with a Glaciogenic 
diamictite (the Grand Conglomérate) approximately 10 to 100 meters (Francois, 1973; Cailteux 
1994). In the upward deepening sequence and overlying the Conglomérate are dolostones, 
shales, siltstones carbonates, and mudstones. The Nguba is exposed in the core of the Lufukwe 
Anticline and probably correlates with the 750 Ma sturtian glacial deposits (Kampunzu et al., 
2005). 
 
Kundelungu Group 
 
Overlying Nguba is the Kundelungu Group (formely Upper Kundelungu) that commences with a 
wide spread tectonically induced conglomerate of up to 50 m thick (`Petit Conglomerate‗) 
containing abundant fragments of Kankotwe Limestone in the Copperbelt region. This was 
previously been interpreted as a glacio-marine or glacio-fluvial deposit, but is now regarded as a 
unit of tectonically triggered mud-flow deposit (Cahen, 1978). This conglomerate is followed by 
sandstones, siltstones, and shale with a few tens of metres thick of limestone near the base. The 
Kundelungu subgroup terminates with a distinctive purple arkose. 
 
 
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2.3.2 Distribution of Mineralisation in the Zambian Copperbelt (Kafue Anticline) 
 
Copper and cobalt mineralisation occurances in Zambia are mainly distributed along the Domes 
region. The main Zambian Copperbelt deposits are defined by two NW-SE trending parallel lines 
of Cu mineralisation which are approximately some 20 km apart, separated by the 
Palaeoproterozoic basement gneisses, granitoids and schists, and Mesoproterozoic 
conglomerates, quartzites and granitoids that make up the Kafue Anticline (Figure 7), within the 
eastern Domes Region of the Lufilian Arc. The majority of the deposits are in the SW of the two 
lines of mineralisation. Each of these two belts is 5 to 20 km wide and up to 150 km long. Ore 
grade mineralisation, however, tends to occupy linear, often more structurally complex, 
semicontinuous bands, up to 2 to 3 km wide, and as much as 17 km long, on the SW limb, 
interrupted by narrow barren gaps and cross folded anticlinal basement ridges (e.g., the Nkana-
Mindola, Nchanga and Konkola strings of deposits). 
 
Figure 6: Zambian Copperbelt deposits distribution along the Kafue Anticline (modified from 
Selley et al., 2005). 
 
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Traditionally the ore deposits of the Zambian Copperbelt have been interpreted to lie within the 
Neoproterozoic Lower Roan Subgroup, composed principally of coarse siliciclastics 
(conglomerate to arkose and siltstone, with lesser carbonates). Some 65% of the mineralisation 
lies within a finer 0 to 100 m thick unit of generally carbonaceous argillites, carbonatic argillites 
and interbedded arenites (Copperbelt Orebody Member)within the coarser clastic succession. A 
further 25% lies within coarser footwall clastics and the remaining 10% within the coarse 
hangingwall clastics. Lithologically, 60% of the ore is hosted by argillites, and 40% in arkose, 
quartzite‘s and conglomerates. 
 
A generalized section through mines of the eastern part of the domes region and how they are 
correlated is shown in Figure 8. 
 
 
Figure 7: Generalized stratigraphic section through the Copperbelt deposits (modified from 
Selley et al., 2005). 
 
2.3.3 Styles of Minerilisation in the Deposit of the Zambian Copperbelt 
 
Minerilsation in the Zambian Copperbelt differs in style among other deposits. The chief of 
styles are: 
 
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(a) Disseminated, generally fine-grained (<0.1 to 3 mm) sulphides within interstitial sites 
between detrital or authigenic grains, randomly distributed or aggregated to form bedding-
parallel streaks and lenses. There is a correlation between the sizes of detrital and sulphide grains 
in this style of dissemination (Selley et al., 2005 and references cited therein). Sulphide may also 
occur replacing detrital grains and authigenic cements, including anhydrite, carbonate, quartz and 
feldspar, as well as diagenetic pyrite, anhydrite, carbonate, quartz, feldspar or heavy minerals 
such as rutile (Binda, 1975; Fleischer et al., 1976); 
 
(b) Vein-Hosted, which may occur as prefolding, layer-parallel and discordant veins or veinlets 
of sulphide, which have sharp contacts with argillaceous strata, and diffuse margins in arenites 
(Annels, 1989). Veining also occurs as late-tectonic, generally coarse-grained sulphide grains 
(commonly >0.5 to 3 cm) in quartz-carbonate (dolomite, calcite) veinlets and subordinate veins, 
which may also contain K-feldspar, chlorite, sericite, biotite, and, very locally, albite, tremolite, 
and below the zone of supergene dissolution, anhydrite. Veinlets are typically ~0.5 to 2 cm wide, 
but may locally be up to several tens of cm thick and extend for distances of several tens of 
metres or more, with densities of 1 to 5 per metre, following and stepping up through the 
stratigraphy. Veins also occupy tension gashes on a small scale and other structures at a high 
angle to bedding. Veins and veinlets can be particularly abundant at the tops and/or bottoms of 
the stratabound orebodies, commonly coinciding with rheologic contrasts and occupying shear 
zones and décollements at these locations. Veinlets often penetrate upwards from arenite hosted 
disseminated mineralisation into otherwise unmineralised, impermeable carbonaceous shales. 
Mineralised veins are restricted to zones of disseminated mineralisation, and contain the identical 
sulphide assemblages found within the enclosing disseminated mineralisation throughout the 
zoned sulphide assemblages (Hitzman et al., 2012, and references cited therein; Sillitoe et al., 
2010). In addition to these Cu±Co vein systems, the Zambian Copperbelt contains volumetrically 
minor Cu-U-Mo-(Au)-(Ni) sulphide assemblages in post-folding veins with associated albite 
haloes, e.g., Mindola, which is the only known economic accumulation (Darnley et al., 1961). 
 
(c) Oxide Ores, usually gradationally overlying the hypogene ore, through a progression from 
primary sulphide (chalcopyrite-bornite-carrollite), through mixed oxide-sulphide (chalcocite- 
copper carbonate/sulphate-cuprite-native copper) to leached capping (usually ~30 m thick). The 
transition usually takes place over an interval of 30 to 70 m of the surface, although in some 
areas of deep faulting, malachite and chalcocite have been found to persist to depths of as much 
as 1 km at Konkola and >600 m at Nchanga Lower. As chalcocite generally occurs closest to the 
surface in the primary sulphide zonation, it is often difficult to differentiate between primary and 
supergene populations of the mineral (Selley et al., 2005). 
 
(d) Cupriferous Mica Mineralisation, which occurs at a number of deposits as an upper and/or 
lower fringe to sulphide orebodies, but never laterally. At the Mimbula-Fitula deposits, 
cupriferous micas persist to a depth of up to 150 m, although the bulk is in the zone from near 
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surface to a depth of 60 m. The cupriferous micas are brown to dark brown in colour, and are 
visually indistinguishable from unmineralised mica. Stockpiles of as much as 150 Mt @ 1.2% 
Cu have been accumulated at Chingola, and resources of in situ mineralisation and stockpiles at 
Nchanga are >275 Mt @ 1 to 1.4% Cu. The mineralisation is refractory. Copper is held in the 
mica lattices in the exchange position, tied largely to hydroxyl groups in interstratified 
phlogopite-cupriferous chlorite micas. Some copper is also absorbed on the surfaces of layered 
mineral structures. Under tropical or sub-tropical conditions of weathering, it has been shown 
that copper may be dissolved out of primary minerals, and where the adjacent rock is micaceous, 
Cu is 'soaked up' by the micas as it passes through the rock. Weathering of primary phlogopite 
causes exchanges of K ions by hydrated Cu and Mg ions, followed by chloritisation. The Cu 
content of this mineralisation ranges from 1 to 8% Cu (Diederix, 1977). 
 2.4 Styles of Minerilisation in Deposits of the Domes Region 
 
Minerilisation is not entirely restricted to in the Zambian Copperbelt. In recent years the western 
area of the domes region (figure 4) has been extensively explored and this has led to 
establishment of big mines such as Lumwana, Kansanshi and Sentinel. Lumwana in 2013 was 
the biggest copper producing mine in Africa with resources of 800 to 1000 Mt @ 0.5 to 0.7% Cu. 
These deposits have differences in the apparent mode of occurrence compared to the main 
copperbelt deposits fringing the Kafue Anticline. Kansanshi Cu-Ag deposit is a vein-hosted type 
occurring in the Nguba Group (Broughton et al, 2002) while the Sentinel Copper deposit is 
hosted in carbonaceous phyllite which is believed to be in the Mwashya (Hitzman et al., 2012). 
In Lumwana the Cu-Co deposit is hosted in the pre-Katangan basement schist (Bernau, 2007, 
unpublished.). 
2.5 Iron Oxide-Copper-Gold (IOCG) Deposits in the Greater Lufilian Arc 
 
The IOCG deposits occur in and surrounding the granitoid massifs of the Lufilian Arc. IOCG 
deposits typically contain an iron-oxide nucleus (magnetite and/or hematite). Magnetite may be 
altered to martite and/or hematite, and the later replacement of part or all of the iron oxides by 
sulphides is common. Light REE and gold are sometimes present in economic quantities; 
uranium content may be significant; many other metals such as silver, cobalt, manganese, nickel 
and Precious Group Element (PGE) may occur in economic concentrations. 
 
The Greater Lufilian Arc of Zambia is a prospective zone for the discovery of additional 
economic IOCG mineralisation. Some of the known IOCG deposits and prospects in the region 
are marked by an abundance of: uranium, light Rare Earth Elements (LREE) minerals, 
phosphates, cobalt, barium-bearing minerals, silver, PGE, titanium-bearing minerals and 
vanadium, as well as copper and/or gold. Some deposits do not contain any anomalous copper. 
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Table 2 describes some features of deposits being exploited and prospects that are akin to IOCG 
deposits. 
 
Table 2: Some IOCG deposit type of the Greater Lufilian Arc in Zambia (after Lobo-Guerrero, 
2012). 
Deposits Tons x10
6
 Cu 
Wt% 
Au g/t Minealisation Stlyes Associated 
Metals 
Associated 
Rocks 
Dunrobin Au 
deposit 
0.002n.a 9.3* Structurally 
controlled; FeOx 
nucleates 
sulphidation+Au. 
Diss+ replacements in 
country rock. Qtz and 
py veins. Replecement 
FeOx bodies. Racoon-
style FeOx-Py 
banding 
Ag, Bi, Mi, 
Pb, Sb, As 
Hosted by foled 
katangan carb + 
gtds 
Nampundwe 
Pyrite Deposit 
23(Cu) 
10(Fe) 
0.79 X n.a. Selective replacement 
in folded sedimentary 
rocks. Specularite-
matrix in polymictic 
multiphase ht bxs 
associated to gtds 
16% pyrite 
57% Fe 
LREE, Co, 
Au? 
Small bodies of 
gab + felsic 
intrusives, 
mag-bear 
diorite: 
lamprophyre 
dykes; qtz pods 
Kalengwe 
deposit 
0.6 ini 
1.9 fin 
16 init 
9.44 
fin 
X n.a. Tabular replacement 
in sediments, ht bxs, 
supergene enrichment 
to chalcocite body; 
polymictic ht bxs: Cu 
sulph dissemination 
50g Ag/t, 
LREE 
Gabic rocks, 
hosted by 
Katangan 
siliciclastics 
syenites + 
granites 
Kitumba 
deposit 
11.9 2.44 0.04 Hypogene 
mineralization occurs 
as diss py and cp, 
associated with stwk 
veining and 
brecciation 
Co, Au, Ag 
and U 
 
Notes: *Dunrobin mine produced over 40,000 oz of gold by 1935. It produced 13,817 oz of gold 
from 1936 to 1961. altn = alteration; bear = bearing; bn = brown; bx = breccia; bxs = breccias; 
carb = carbonate; cp = chalcopyrite; diss = disseminated, dissemination; dol = dolomite, 
dolostone; FeOx = iron-oxide; fin = final; frac = fracture; gab = gabbro; gtd = granitoid; ht = 
hydrothermal; init = initial; LREE = light rare earth elements; mag = magnetite; n.a. = not 
available; po = pyrrhotite; py = pyrite; qtz = quartz; rk = rock; stwk = stockwork ;sulph = 
sulphide; undim. = undimensioned; X n.a. = metal is present but data is not available. 
 
 
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CHAPTER THREE 
 METHODOLOGY AND CHARACTERISTIC OF DEPOSITS 
3.1 Introduction 
 
This chapter focuses on the selection of deposits that are representative and also describes the 
geology and geophysical characteristics of the selected deposits. 
 
3.2 Methodology Flow Chart 
 
Figure 9 summarizes and illustrates the process applied to the research undertaken, from 
literature review through to report writing. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Literature Review 
Deposit Selection 
Criteria 
Forward modelling of 
Selected Deposits 
Data 
Interpretation 
and Analysis 
Report Writing 
Geophysical Data compilation 
of Selected Deposits (gravity 
and magnetic Data) 
Figure 8: Methodology flow chart illustrating in summary the methodology 
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3.3 Selection and Characteristization Copper Deposits in Zambia 
 
To avoid biasness in the selection of deposits and to make sure that representative exploration 
models are developed, deposits were selected based on the geographical location, the tectonic 
setting, style of copper mineralization and the mode of exploitation. The following copper 
deposits were selected (Figure 10 a and b): 
 The Kitumba IOCG deposit located in Mumbwa District, central Zambia within extreme 
southern portion of the Neoproterozoic Lufilian Arc and to be exploited by underground 
means; 
 The Konkola Deep Strata-bound sedimentary copper deposit located in Chingola District, 
Copperbelt Zambia within the Zambian Copperbelt and being exploited by Underground 
means; 
 The Chambishi Strata-bound sedimentary copper deposit located in Kitwe District, 
Copperbelt Zambia within the Zambian Copperbelt and being exploited by open pit; 
 Lumwana‘s Chimiwungo Strata-bound metamorphic copper deposit located in Solwezi 
District, Northwestern Zambia within the domes region and being exploited by open pit 
means; and 
 The Kansanshi Vein deposit type located in Solwezi District, northwestern Zambia within 
the Domes Region and being exploited by open pit means. 
 
 
 
Figure 9: (a) Location of the selected deposits. (b) Tectonic controls of the selected deposits. 
 
 
(a) (b) 
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3.4 The Kitumba Deposit 
3.4.1 Geographic Location 
 
Kitumba Deposit is located in Mumbwa District in Central Province Zambia and it‘s about 160 
km west of Lusaka City(#Location: 12° 6' 0" S, 26° 26' 0" E). 
3.4.2 Tectonic Setting 
 
The Kitumba deposit is located within a giant iron oxide alteration system which is developed 
along a 26 km long north-northwest to south-southeast trending structural corridor referred to as 
the Kitumba Fault Zone (KFZ) within the extreme southern portion of the Neoproterozoic 
Lufilian Arc (Robertson, 2013). 
 
3.4.3 Geology of Kitumba Deposit 
 
The geology of the Mumbwa area is described by Cikin and Drysdall (1971). The region is 
dominated by metasedimentary rocks of the upper units of the Neoproterozoic Katanga 
Sequence. These rocks are intruded by the large syn- to post-tectonic 566-533 Ma Hook 
Granitoid Suite and by younger post-tectonic syenites, diorites, porphyry granites, granites, 
diorites and gabbros. The east-northeast trending Mwembeshi Shear Zone (MSZ) runs along the 
southern margin of the Hook Granitoid Suite. The geology of the Kitumba deposit area is shown 
in Figure 11. 
. 
 
Figure 10: Geological Map of Kitumba Deposit (after Intrepid Mines Limited, 2014). 
 
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The northern part of the license is underlain by metasedimentary rocks of the middle to lower 
Kundelungu Group of the upper Katanga Sequence. These comprise carbonates and calc-arenites 
interlayered with shales and siltstones. The western and southwestern part of the license area is 
dominated by intrusive granitoids of the Hook Granitoid Suite. The deposit is hosted within a 
hematite-dominated breccia system which is developed along the Kitumba Fault Zone (KFZ) and 
which outcrops as a prominent north-south trending ridge forming part of the Kitumba Hills. 
Three principal rock type associations are recognised at Kitumba. Kundulungu Group calcareous 
siltstones and argillites are intruded by quartz-feldspar porphyry granite. These rocks are in turn 
extensively intruded by a feldspar porphyry diorite/syenite complex. The system is zoned from 
north to south, with deeper level magnetite dominated alteration south of Kitumba to the Sugar 
Loaf deposit (3.8 km southwest of Kitumba) and higher level hematite dominated alteration over 
Kitumba itself. These correspond to magnetic highs and lows, respectively. 
 
Copper mineralisation at Kitumba comprises a simple hypogene sulphide assemblage that is 
extensively overprinted by a complex largely redistributed supergene oxide assemblage. 
Kitumba represents a deeply weathered IOCG system with weathering and oxidation extending 
up to 500 m depth. Deep weathering is particularly pronounced in the vicinity of the KFZ and 
zones of high fracture intensity, where leaching of sulphides has generated acid, resulting in a 
porous and vuggy core, whilst iron is largely preserved. Hypogene mineralisation at Kitumba 
mainly occurs as disseminated pyrite and subordinate chalcopyrite, associated with stockwork 
veining and brecciation. Semi-massive concentrations of pyrite ± chalcopyrite are observed in 
places and are mostly concentrated beneath the richest supergene mineralisation adjacent to the 
KFZ. Primary sulphides are largely preserved within iron carbonate altered zones, sometimes 
relatively shallow, where carbonate has acted as a buffer preserving hypogene assemblages. A 
significant proportion of the mineralisation occurs in the form of secondary copper minerals 
withinthe supergene zone. Supergene enriched material is concentrated from 200 m below 
surface where it occurs as chalcocite +/- malachite, pseudomalachite, cuprite, native copper, and 
copper wad. The distribution of secondary copper minerals is related to remobilisation of copper; 
with secondary copper minerals commonly occurring along fractures and as linings in cavities. A 
section through the deposits is shown in Figure 11 and the geophysical properties of the 
lithologies tabulated in Table 3. 
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Figure 11: The geological section of Kitumba deposit and its geophysical properties (after 
Intrepid Mines Limited, 2014). 
 
Table 3: Gravity and Magnetic properties of the Kitumba Deposit (after Intrepid Mines Limited, 
2014). 
Lithology Estimated thickness 
(m) 
Density 
 (gu) 
Mag Sus (x 10
-3
) 
 SI 
Laterite 45 1.92 0.5 
Iron Oxide 70 5.18 60000 
Quartz-feldspar granite 170 2.64 2.5 
Feldspar Porphyry syenite >500 2.74 60 
Breccia 80 3.96 0.0004 
 
 
 
3.5 The Konkola Deep Deposit 
 3.5.1 Geographic Location 
 
The Konkola Deep deposit is located in Chililabombwe in the Copperbelt Province of Zambia 
about 30km from the town of Chingola. Konkola Deep deposit has coordinates (#Location: - 12° 
22' 45"S, 27° 49' 45"E). 
 
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 3.5.2 Tectonic Setting 
 
The Konkola section of the Zambian Copper Belt comprises a near continuous, NW-aligned, 
close to 20 km long by 2 to 4 km wide ribbon of ore within the Neoproterozoic Lower Roan 
Subgroup. It extends from the northern margin of the regional 'Kafue Anticline' basement block, 
and is down-folded, to emerge again on the rim of the Konkola basement dome to the northwest. 
 
3.5.3 Geology of Konkola Deep Deposit 
 
This deposit is typically known as the Bancroft. The geology of this area is characterized by the 
higher grounds of Konkola being underlain by beds of the Basement Complex and lower roan 
group, and the low-lying country is underlain by a succession of shales and dolomites of the 
Upper Roan, Mwashia and Kundelungu Groups (Figure 13). A section through the deposits is 
shown in Figure 14 with the geophysical properties of the lithologies tabulated in Table 4. 
 
 
Figure 12: Geological map of Konkola Deep deposit and the surrounding area (after Porter 
GeoConultancy, 2014). 
A 
B 
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Figure 13: The geological section through A-B of Konkola Deep deposit (after Porter 
GeoConultancy, 2014). 
. 
Table 4: Gravity and Magnetic properties of the Konkola Deep deposit (Telford el at, 1994). 
Geology Thickness 
(m) 
Density 
(gu) 
Magnetic Susceptibility 
 (x 10
-3
)SI 
Mwashya Subgroup 300-600 2.80 1.03 
Upper Roan Supgroup dolostone 100-450 2.42 0.23 
Shale and Grit 40-160 2.42 0.37 
Hangingwall Aquifer dolostone 15-75 2.42 0.23 
Hangingwall Quarztite 10-150 2.6 4 
Ore Shale 0-60 2.87 0.95 
Footwall Conglomerate 0-35 2.5 0.35 
Footwall Sandstone 0-20 2.35 0.4 
Porous Conglomerate 15-50 2.5 0.35 
Argillaceous Sandstone 5-20 2.35 0.4 
Footwall Quartzite 0-300 2.6 4 
 
 
 
B 
A 
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3.6 The Chambishi Main Deposit 
3.6.1 Geographic Location 
 
Chambishi area has three deposits namely: Chambishi Southeast, Chambishi West and 
Chambishi Main deposits. These deposits are ~360 km north of Lusaka and 28 km NW of Kitwe. 
Chambishi Southeast deposit is centred on a point ~10 km NW from the Mindola mine, while the 
Main and West deposits, which are separated by a narrow barren gap, are a further ~7 km to the 
NW, coordinates (#Location: 12° 39' 36"S, 28° 3' 21"E). 
3.6.2 Tectonic Setting 
 
The Chambishi deposits are hosted by the Neoproterozoic Lower Roan Group Ore Formation of 
the Katanga Supergroup, within the Chambishi-Nkana basin, located on the mid-southwestern 
flank of the 'Kafue Anticline'. 
 
3.6.3 Geology of Chambishi Main Deposit 
 
The geology of this area is characterized by an exposed sequence of the Katanga Super group 
and the Basement Rocks in the flanks(Figure 15). The Lower Roan Group hosts the Ore 
Formation around Chambishi. The Ore Formation has an averages 30 m thickness near-surface, 
thinning to 20 m down-dip, and to 6 m over granite basement highs. It consists of fine-grained 
biotite-quartz argillite with a basal zone that is strongly contorted, schistose, carbonate-rich, cut 
by quartz-dolomite-anhydrite veins and containing coarse aggregates of bornite and chalcopyrite. 
Associated quartz veins carry the same sulphide minerals. Above the basal zone, ore occurs as 
finely disseminated bornite and chalcopyrite, grading down-dip and up-section into pyrite. 
 
The Lower Roan Group is strongly deformed in the vicinity of Chambishi with the Chambishi 
Monocline as the main structure. Most intense folding occurs in the Ore and Hangingwall 
Formations. The orebodies pinch-out down dip corresponds to a change in the gradient of the 
footwall thickness. Chalcopyrite is the dominant Cu sulphide with minor bornite. Pyrite and 
pyrrhotite are typical co-existing gangue phases. Co mineralisation is unevenly distributed within 
the Cu orebody and present as Co-pyrite and carrollite. A section through the deposits is shown 
in Figure 16 with the geophysical properties of the lithologies tabulated in Table 5. 
 
 
 
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Figure 14: The geological map of Chambishi deposits (modified after Croaker, 2011). 
 
 
Figure 15: Representative cross section through the Chambishi Main deposit(modified after 
Croaker, 2011). 
 
 
 
A 
B 
B A 
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Table 5: Gravity and magnetic properties of the Chambishi Main deposit (Telford el at, 1994). 
Geology Thickness 
(m) 
Density 
(gu) 
Magnetic Susceptibility 
 (x 10
-3
)SI 
Gabbro 170 3.03 70 
Dolostone 200 2.42 2.0 
Sandy Talc Schist 75-90 2.5 1 
Schist and Quartzite 25 2.62 2.7 
Upper Quartzite 12-25 2.6 4 
Interbedded Schist and Quartzite 5-25 2.62 2.7 
Hangingwall Quartzite 3-12 2.6 4 
Copperbelt Ore Member 5-30 2.87 1.5 
Mindolo Clastic Formation 0-150 2.48 2.2 
Basement Granitoid >300 2.8 2.6 
 
3.7 The Chimiwungo Deposit 
3.7.1 Geographic location 
 
The Lumwana tenement is located 220 km northwest of the Zambian Copperbelt, and 65km from 
the provincial capital of Solwezi in the North Western Province of Zambia, (#Location 
coordinates: 12° 10' 44'' S , 25° 51' 5'' E). Lumwana tenement comprises of three ore bodies of 
which only two have been proven, these are Chimiwungo and Malundwe deposits. The Lubwe 
deposit is not economical for mining. 
3.7.2 Tectonic Setting 
 
The Chimiwungo copper deposit is hosted within the Middle Thrust Sheet domain of the 
Mwombezhi Dome, one of several basement inliers of early to Mid-Proterozoic age. The 
basement domes are interpreted as antiformal stacks above mid to lower crustal ramps and 
consist of granite gneiss, migmatites and schist that vary in metamorphic grade from amphibolite 
facies in the domes region to green schist facies in the Kafue Anticline (Daly et al., 1984). 
 
3.7.3 Geology of Chimiwungo Deposit 
 
The Chimiwungo deposit consists of lenticular horizons of sulphide mineralized kyanite schist 
that correlate poorly across the deposit. The copper mineralisation is hosted almost entirely 
within high