TECHNICAL REPORT OF THE 2003 EXPLORATION PROGRAM ON THE BURNSTONE
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1 TECHNICAL REPORT OF THE 2003 EXPLORATION PROGRAM ON THE BURNSTONE GOLD PROJECT MPUMALANGA PROVINCE, REPUBLIC OF SOUTH AFRICA GREAT BASIN GOLD LTD. DATE: MAY 19, 2004 BY: Daniel Kilby, PEng, Great Basin Gold Ltd Robert Cluff, MSc, Great Basin Gold Ltd
Transcript of TECHNICAL REPORT OF THE 2003 EXPLORATION PROGRAM ON THE BURNSTONE
1
TECHNICAL REPORT
OF THE
2003 EXPLORATION PROGRAM
ON THE
BURNSTONE GOLD PROJECT
MPUMALANGA PROVINCE, REPUBLIC OF SOUTH AFRICA
GREAT BASIN GOLD LTD.
DATE: MAY 19, 2004
BY:
Daniel Kilby, PEng, Great Basin Gold Ltd Robert Cluff, MSc, Great Basin Gold Ltd
2
TABLE OF CONTENTS
1. EXECUTIVE SUMMARY 1
2. INTRODUCTION AND TERMS OF REFERENCE 3
3. DISCLAIMER 4
4. PROPERTY DESCRIPTION AND LOCATION 4
5. CLIMATE, PHYSIOGRAPHY, ACCESS & INFRASTRUCTURE 7
6. EXPLORATION HISTORY 8
7. GEOLOGICAL SETTING 9
Regional Geology - Witwatersrand Basin 9
Deposit Characteristics 10
South Rand and Property Geology 11
a. Stratigraphy 12
b. Structure 15
c. Footwall Geology 18
d. Sedimentology 18
8. EXPLORATION 20
a. 2003 Program 20
b. 2004 Program 21
Kimberley Reef Stratigraphy and Mineralisation 21
Area 1 21
Area 2 22
Area 3 23
9. SAMPLING METHOD AND APPROACH 23
10. SAMPLE PREPARATION, ANALYSIS AND SECURITY 24
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11. ADJACENT PROPERTIES 26
12. MINERAL RESOURCE ESTIMATES 29
13. INTERPRETATION AND CONCLUSIONS 30
14. RECOMMENDATIONS 30
15. REFERENCES 32
16. DATE 33
17. CERTIFICATES 33
APPENDIX A 36
ILLUSTRATIONS 42
LIST OF FIGURES PAGE
Figure 4.1 Burnstone Property Location 4 Figure 4.2 Mineral Rights 6 Figure 7.1 Stratigraphic Column 9 Figure 7.2 Regional Kimberley footwall lithology and palaeo-current directions 11 Figure 7.3 Geology of the South Rand Basin 12 Figure 7.4 Burnstone Gold Deposit-Areas and Major Faults 16 Figure 10.1 Flow Sheet of Sampling and Analytical Process 24 Figure 11.1 Kimberley Reef Morphology at Evander Goldfield 26 Figure 11.2 Gold Isocons In the Kimberley Reef - Evander Goldfield 28 Figure 11.3 Kimberley Reef Channel Development – Evander Goldfield 29
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1. EXECUTIVE SUMMARY The Burnstone Gold Project is located approximately 80 km southeast of Johannesburg, South
Africa, in the South Rand area of the Witwatersrand Basin. The Project area covers 45,676
hectares situated on portions of 22 mineral farms. In November 2002, Great Basin entered
into an agreement with Southgold Exploration (Pty) Limited (“Southgold”), a private South
African resource company, whereby Great Basin could purchase up to 100% of Southgold on
a phased basis, and acquire the right to purchase all the mineral rights of the Burnstone Gold
Project. Great Basin completed the purchase of Southgold in early 2004. Southgold and
Great Basin have pursued involvement of a Black Economic Empowerment Company as
required by the recently enacted Mineral and Petroleum Resources Development Act.
Gold was first discovered in the southeastern portion of the South Rand in 1887, leading to the
establishment of a number of small mines and prospects, which operated, intermittently from
1892 to 1962. Exploration drilling in the Burnstone Project area was conducted intermittently
during the period 1974 to 1993, initially by Union Corporation Ltd., and later by Gencor.
During this period, Anglovaal Limited also drilled the VFN-series of holes. Three boreholes
(SG1 through SG3) were drilled during the late 1990’s and early 2000, and a further 15
boreholes (SG4 – SG18) were drilled by Southgold from May to July 2002.
During 2003, Great Basin drilled 101 core holes in Areas 1, 2 and 3. A total of approximately
65,193 metres were drilled as primary holes along with an average of three deflections for
each primary hole. An additional 33 holes, totalling 21,630 metres, have been drilled in Areas
1, 2, 3 and 4 from January 2004 to April 30, 2004. The 2004 holes consist of a primary hole
along with an average of 5 deflections.
The South Rand area is located in the northeastern part of the Witwatersrand Basin. In the
South Rand, the Witwatersrand sequence is thinner than in other parts of the Basin. The West
Rand Group, comprising about 1,500 m of alternating quartz arenite and shale units,
unconformably overlies the Archaean granite-greenstone basement rocks. The overlying
Central Rand Group strata is approximately 900 m thick and includes the auriferous
Kimberley Reef horizon. The Johannesburg Subgroup, including the Bird amygdaloidal lava
and the Kimberley shale, is about 300 m thick. The Turffontein Subgroup is approximately
600 m thick and is made up of a sequence of quartz arenites and conglomerates that correlate
with the Elsburg Formation.
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Gold occurs in a conglomerate unit called the Kimberley Reef that occurs at the base of the
Turffontein Subgroup. This horizon is developed on an unconformity surface and may rest
directly on the Kimberley shale or the Main Bird quartzites or amygdaloidal lava.
The sedimentological features, i.e. pebble size, degree of sorting, and mineralogical
composition, of the Kimberley Reef conglomerate are somewhat variable. These variations
are a function of the environment of deposition, the nature of the source area supplying
detritus, and the extent to which later hydrothermal or metamorphic fluids have passed
through the reefs. Typically, the Kimberley Reef comprises between 70 and 90% well-
rounded pebbles, made up predominantly of milky vein quartz together with lesser chert, blue
quartz, jasper, quartzite, shale and other rock fragments. Pebbles are cemented in a matrix of
finer, more angular quartz grains and a variety of phyllo-silicate minerals including sericite,
pyrophyllite, muscovite, chlorite and chloritoid.
Structural mapping revealed two structural elements strongly influence the distribution of rock
units in the Burnstone project area. A regional horst block has been elevated such that the
Kimberley Reef and its host units occur at depths shallower than the regional norm. The horst
is formed through the development of west-northwest trending faults whose dip direction
reverses from south dipping, along the southern boundary of the property to north dipping
along the northern boundary. The width of the horst block narrows to the southeast and
widens to the northwest. This flaring of the horst is caused by the divergence in strike
between the north and south bounding faults. Within this structural regime, west-northwest
trending structures are linked by arcuate, sigmoidal extension zones that are commonly
oriented east-west. These structural zones are infilled by later dolerite dykes in many places.
Surface geological data does not provide any evidence for the presence of low angle thrust
fault duplexes and stratigraphic shortening or contraction. The overall structural environment
is dominated by sinistral, trans-tensional faults. The stratigraphic section is also elevated or
depressed, locally, by the presence of regional synform-antiform couples. These folds migrate
and change in intensity relative to their position in relation to the northern border faults, and to
their proximity with basement rocks and lower Witwatersrand successions. Closer to the
northern bounding faults, the folds are characterized in some places by short steep limbs, and
in other places by long flat limbs. Farther away from these faults, the stratigraphy occurs in
gentle, open, antiform-synform couples.
Geological interpretation from the recent Great Basin drilling, combined with a detailed
review of the historical data, indicates that the Burnstone deposits are cut by a number of
northwest to east-west trending faults that are down-thrown on their northeast side. The
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shallow block on the southwest side of Area 1, positions the Kimberley Reef within 250 m of
surface.
Based on the recent detailed drilling and compilation, there is an excellent understanding of
the geology, sedimentology and structure of the lithologies encountered in the Burnstone
project area, particularly Areas 1 and 2. It is recommended that additional drilling be
continued in Areas 2, 3 and 4, along with the continuation of the surface mapping and general
geological compilation work, to improve the geological and exploration models developed so
far and to test the additional lands that have been added to the project area since beginning of
2003, including:
collation of all available geological data to date to define/refine the current tectono-
sedimentary exploration model as well as refine targets to optimise future drilling
programs;
continuation drilling Areas 2, 3 and 4 to test and delineate mineralised shoots and
decrease the inter-borehole spacing in order to increase geological and geo-statistical
confidence levels;
continuation the surface mapping program with particular emphasis on recording
stratigraphy and structure; and
consolidation of the existing property databases for additional properties acquired.
A budget of $4,833,000 is proposed, including 40,000 m of drilling with support costs, as well
preliminary engineering and environmental work.
2. INTRODUCTION AND TERMS OF REFERENCE This technical report is filed in conjunction with the Annual Information Form of Great Basin
Gold Ltd., to document the exploration programs carried out by the Company on the
Burnstone Gold Project in 2003 and early 2004.
Sources of information utilized to produce this report include the Qualifying Report for the
Burnstone property of November 28, 2002 and appended Report on the Burnstone Property,
May 9, 2003, by GeoActiv (Pty) Ltd.; the geological and drilling database compiled by Great
Basin to the end of 2003; and various published papers on the East Rand and Evander basins.
Further details are provided in Section 21 – References.
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Mr. Daniel Kilby, P. Eng., is Great Basin’s site manager and the Qualified Person for this
technical report. Mr. Kilby worked at the Burnstone property from February 11 to November
15, 2003 and January 5 to April 19, 2004, and supervised Great Basin’s 2003 and 2004
drilling program. Great Basin’s site consultants are Harry Meadon, Pr. Sci. Nat., and Kobus
Badenhorst, Pr. Sci. Nat., of GeoActiv (Pty) Ltd of Roodepoort, Gauteng, South Africa.
3. DISCLAIMER
In preparing this report the authors relied on:
Land title information assembled by Great Basin;
Geological reports completed previously by Behre Dolbear and GeoActiv;
Data from historic drill holes and holes drilled by Great Basin to April 30, 2004; and
Information from published reports on the Witwatersrand Basin and its goldfields.
4. PROPERTY DESCRIPTION AND LOCATION The Burnstone Project area is situated in the Mpumalanga Province of South Africa,
immediately southeast of the town of Balfour, and approximately 80 km to the southeast of
Johannesburg (Figure 4.1).
East Rand Goldfields
Evander Goldfields
South Rand Basin
West Rand Goldfields
Welkom Goldfields
Klerksdorp Goldfields
Carletonville GoldfieldsAnglo GoldGold FieldsHarmony
DRD
DRDAnglo Gold
HarmonyAnglo GoldGold Fields
Placer DomeHarmony
Harmony
50 km
Burnstone Gold Project
Central Rand Group
West Rand Group
Basement Granite
Johannesburg
Balfour
BURNSTONEAU DEPOSIT
SOUTH AFRICA
NAMIBIA
BOTSWANA
ANGOLA
ZAMBIA
ZIMBABWE
MO
ZA
MB
IQU
E
500 km
AFRICA
South Africa
Atlantic
Ocean
Indian
Ocean
Cape Town
Johannesburg
WitwatersrandGoldfield
Avgold
Kronstad Goldfields
Figure 4.1. Burnstone Property Location (modified after Anhaeuser & Maske, 1986)
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The Burnstone project encompasses 45,676 hectares and is situated on portions of 22 farms
contiguous over the deposit.
The mineral rights under option (permitted and non-permitted) are listed below and shown in
Figure 4.2:
Owner Ha %
Gold fields 13,568 30%
Rietbult Estates 7,288 16%
Southgold 2,287 5%
Taurus 1,365 3%
Puma 2,744 6%
Private 18,424 40%
TOTAL 45,676 100%
At present, Great Basin has not negotiated any surface rights for the Burnstone property. Like
many countries, South African surface rights are separate from mineral rights. However,
South African mineral law gives mining companies the right to gain surface access to drill and
to obtain permits for discovered minerals. Since mineral rights holders can gain surface rights
where it is necessary to exploit mineral rights, the necessary surface rights will be acquired
once it is finalized how the Burnstone property will be developed.
Property AgreementIn November 2002, Great Basin entered into an agreement with the shareholders of a private
South African company, Southgold Exploration (Proprietary) Limited (“Southgold”) to
acquire up to 100% of Southgold (“the Southgold Agreement”). Southgold holds the rights to
purchase the Burnstone Gold Project, and any subsequent mining would be subject to
government legislation, which provides for historically disadvantaged South Africans to earn
an interest in mining developments.
In early 2004, Great Basin exercised its option and completed the purchase of 100% of
Southgold by making cash, share and share purchase warrant payments to Southgold
shareholders in two staged tranches, totalling US$3.25 million (of which US$1.25 million was
paid on signing), 21 million shares and 10.5 million share purchase warrants exercisable at
US$0.75 for one year from the date of issuance. Exercise of the share purchase warrants is
subject to an accelerated expiry provision under certain conditions.
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Siya themba
13
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15
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29
26 13
RE
27
14
25
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23
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11RE
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RE/1
(Ptn/4)7
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RE/4
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2
ROODEPOORT 598 IR
DOORNHOEK 577 IR
ZYFERFONTEIN 576 IR
BAKKIESFONTEIN
568 IR
RIETVALEI
546 IR
SPRINGFONTEIN549 IR
RUSTFONTEIN
548IR
KLEINFONTEIN
567 IR
BAARNAARDSKOP 637 IR
HAARTBEESTFONTEIN 638 IR
5 km
VANKOLDERSKOP
550 IR
VANKOLDERSKOP
552 IR
VANKOLDERSKOP
547 IR
DAGBREEK
551 IR
BRAKFONTEIN 513 IR
VLAKFONTEIN
558 IR
VLAKFONTEIN 556 IR
RIETBULT ESTATES 505 IR
RIETFONTEIN 561 IR
VLAKFONTEIN
569 IR
GreylingstadGreylingstadGreylingstad
BalfourBalfour
-350
00
mE
-2970000 mN
-2960000 mN-2960000 mN
-2940000 mN
-2950000 mN -2950000 mN
-2940000 mN
-2980000 mN
-45
000
mE
Mineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights HeldMineral Rights Held
Area 1
Area 2
Area 3
Area 4
Area 3
Figure 4.2. Mineral Rights
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5. CLIMATE, PHYSIOGRAPHY, ACCESS & INFRASTRUCTURE The Burnstone property is situated in the Mpumalanga Province approximately 80 km
southeast of the city Johannesburg and east of the town of Balfour. The property is connected
to Balfour by paved and gravel roads that cross the property and Balfour by paved road to the
National Johannesburg – Durban highway N3. The nearest major airport is the Johannesburg
International Airport located west of Johannesburg, some 70 km northwest of the Burnstone
property.
The property is also crossed by the national grid power lines and by two rail lines, one being
the main Johannesburg, Durban trunk line. There are three rail sidings on the property. The
Rand Water Board trunk water main into Balfour has excess pipeline capacity sufficient to
service a mine or mill’s needs. An independent rock quarry producing crushed stone is also
located on the surface lands to the southwest of the Burnstone Area 1 deposit. The stone
quarry is sufficiently distant as to not interfere with the Burnstone Project development.
The Burnstone property is located on the South African Highveld at an average altitude of
1,670 m. Topographic relief is gently rolling grassland terrain, which is amenable to
construction and operation of a mine and mill, including tailings impoundment facilities and
waste rock storage sites. There is more than adequate space in which to locate mine facilities
on the lands overlying the Burnstone deposit.
The area has a mild climate, with about six weeks of chill and frost in mid-winter (July-
August). Due to the relatively high altitude, winter nights can be cool and freezing can occur.
The rainy season occurs during the summer and drought conditions usually prevail in winter.
Summer rainstorms are often ferocious and can be accompanied by substantial lightning.
Hailstorms occur occasionally.
The Balfour area has been intensively farmed for corn and hay for nearly 100 years,
consequently there is very little indigenous vegetation remaining in the property area. The site
development should it occur, including declines, mineshafts, mill and tailings storage facilities
would be located some 6.5 km from the village of Balfour. Preliminary reviews indicate that
there appear to be few, if any, environmental concerns.
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6. EXPLORATION HISTORY Gold was first discovered in the southeastern portion of the south Rand area in 1887, leading
to the establishment of a number of small mines and prospects, which operated, intermittently
from 1892 to 1962. Antrobus (1986) defined the South Rand as a small 30 km2 area which
included four small mines south of Greylingstad, namely the Heidelberg-Roodepoort, Kildare,
Hex River and Southeast Witwatersrand Mines, all of which are now dormant. Pretorius
(1964) and De Jager (1986), however, applied a broader definition in which the gold field
included the entire area south of the Sugarbush fault.
The Heidelberg-Roodepoort Mine was the largest single producer in the area. Here, the
Kimberley Reef is well developed and characterised by pronounced chloritisation and
pyritisation, particularly along the bottom contact. The reef was consistently viable over the
mine lease area and operations were eventually terminated in 1942, at a depth of around 300
m, by a fault which vertically displaced the reef, from which position it was mined from the
Kildare Gold Mine property.
Exploration drilling in the Burnstone Project area was conducted intermittently during the
period 1974 to 1993, initially by Union Corporation Ltd., and later by Gencor. During this
period, the VFN-series of holes were also drilled by Anglovaal Limited (now known as
Avgold Limited). Three boreholes, SG1 through SG3 were drilled during the late 1990’s and
early 2000, and a further 15 boreholes (SG4 – SG18) were drilled by Southgold from May to
July 2002.
Great Basin acquired its option to purchase Southgold in November 2002. As part of the
transaction, Great Basin committed to completing a US$1.5 million program directed at
further testing the Area 1 deposit in preparation for feasibility studies. The program began
with a regional aeromagnetic survey, which provided a structural interpretation that greatly
assisted in identifying structural discontinuities affecting the project area. Diamond drilling
was then carried out in Area 1. The objective of the drilling was to better define and increase
the confidence in the resource estimate for the Area 1 gold deposit. The program, comprising
30 holes (21,716 m in primary holes and valid deflections) of infill and step-out drilling, was
carried out from January to April 2003. Drilling continued throughout the remainder of 2003
and into 2004. Drilling took place in the central portions of the Burnstone project area. Since
commencement of the drill program in January of 2003 to April 30, 2004, Great Basin Gold
completed 134 drill holes totalling 86,823 metres of NQ core drilling.
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7. GEOLOGICAL SETTING
Regional Geology - Witwatersrand Basin The Witwatersrand Basin is underlain by an Archean (>3.1 Ga) granite-greenstone basement
and the 3,086 – 3,074 Ma Dominion Group. It is overlain, unconformably, by rocks of the
Ventersdorp (2.7 Ga), Transvaal (2.6 Ga) and Karoo (280 Ma) Supergroups.
The first significant classification of the stratigraphy of the Witwatersrand Supergroup was
presented by Mellor (1917) and was based on his work in the Central Rand goldfield. This
grouping was found to be applicable on a basin-wide scale, although a more detailed appraisal
would uncover significant variations in the nature and thicknesses of the sequences from one
portion of the basin to another. In 1980, the South African Committee for Stratigraphy
(“SACS”) published a detailed lithostratigraphic classification in which the Lower and Upper
Witwatersrand systems were renamed the West Rand and Central Rand Groups, respectively.
The Hospital Hill, Government Reef and Jeppestown Series were classified as Subgroups and
the Main – Bird and Kimberley – Elsburg Series renamed the Johannesburg and Turffontein
Subgroups, respectively (Figure 7.1).
Figure 7.1. Witwatersrand Stratigraphic Column (Burger pers. Comm, 1982)
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The northern part of the Witwatersrand Basin (Central Rand, East Rand, Evander and South
Rand Basins) was dominated by syn-depositional sinistral oblique-reverse to strike-slip
tectonics along major, ENE-trending, steeply dipping fault systems which formed in response
to a craton-wide, NE-SW compressional stress regime (Myers et al., 1990, 1992; Charlesworth
& McCarthy, 1990; Spencer, 1992). In comparison to the wrench tectonics along the northern
margin, the western margin of the Witwatersrand Basin was characterised by syn-depositional,
easterly verging thrust tectonics, leading to the formation of major low-angle thrust faults and
thrust-related folding of the Witwatersrand Supergroup strata (e.g. Vermaakt, 1995; Antrobus
et al., 1986). In the areas of widespread mining in the Central and Western Rand areas, the
structure is far better understood than in the Burnstone project area of the South Rand Basin.
Large thrusts observed in adjoining mines over larger areas would be less obvious and more
difficult to define in the South Rand Basin. Low angle thrusts could well exist in the
Burnstone project area, but would only be identified and located during mining activities.
Continuous NE-SW compression peaked in mid-Ventersdorp-time, leading to NW-SE
directed crustal extension, the relaxation of all pre-existing, syn-Witwatersrand Supergroup
faults and the formation of major normal and strike-dip faults resulting in the development of
local grabens as well as roll-over anticlines (McCarthy et al., 1990; Vermaakt & Roering,
1991; Myers et al, 1992).
Evidence exists in the literature for a possible late-Ventersdorp to pre-Transvaal
compressional event associated with north to northeast directed thrusting along the northern
margin of the Witwatersrand Basin (Hilliard, 1994; Vermaakt, 1995; Coetzee et al., 1995;
Hilliard & McCourt, 1995).
Deposit Characteristics The Witwatersrand Basin is one of the most intensively studied sedimentary sequences in the
world. It is widely agreed by geologists that deposition took place along the interface between
a system of large rivers and a major body of still water or an inland sea. The basin is filled
with approximately 14,000 m of sedimentary and subordinate volcanic rocks, which have been
folded along a northeast to southwest axis into an asymmetrical synclinorium (Pretorius,
1974). At present, most workers accept a foreland model for the development of the Basin, not
unlike that proposed by Burke et al. (1986). Stratigraphically, the vast majority of economic
placers have been found in the upper Subgroup of the Witwatersrand Supergroup, the Central
Rand. However, it should be emphasized that the principal placers of the various gold fields of
the Basin do not all occur at the same stratigraphic level.
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The goldfields of the Witwatersrand Basin are considered to signify major, diachronous, entry
points of coarse-grained sediment into the basin. The deposits formed probably represent
laterally coalesced fluvial braid-plains, where gold was concentrated within conglomerates
developed primarily on unconformities of the progressive type. Those parts of the proposed
braid-plains that contain economic gold concentrations commonly extend for 10 to 30
kilometres down depositional dip, and for up to 10 to 12 km along depositional strike. Some
of the major goldfields are separated by “gaps”, areas where no economic placers have been
discovered. Figure 7.2 shows the formation parameters of the East Rand Basin, the Evander
Basin and the South Rand Basin.
Evander
Basin
South
RandBasin
EastRandBasin
Figure 7.2. Regional Kimberley footwall lithology and palaeo-current directions (GeoActiv, 2002)
South Rand and Property Geology In the South Rand, conglomerates are substantially less well understood compared to other
parts of the Witwatersrand Basin. The only viable horizon worked in all of the now defunct
mines was the Kimberley Reef, which occurs at the base of the Turffontein Subgroup. This
horizon is developed on an unconformity surface and may rest directly on the Kimberley shale
or the Main Bird quartzites or amygdaloidal lavas. It was previously thought that the reef
mined at the Edenkop Mine was equatable with the Coronation Reef of the Government
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Subgroup in the Klerksdorp gold field (Pretorius 1964), but more recently it has been shown
to be the same as the Kimberley Reef mined elsewhere in the South Rand, Figure 7.3.
Balfour
Kimberley Shale
Quartzites
Ventersdorp Lavas
Basement Rocks
Area 1
Geological Legend
Kimberley Reef
Balfour
Kimberley Shale
Quartzites
Ventersdorp Lavas
Basement Rocks
Area 1
Geological Legend
Kimberley Reef
Figure 7.3. Geology of the South Rand Basin
a. Stratigraphy The sequence in the South Rand is considerably thinner than in other parts of the
Witwatersrand Basin. The West Rand Group unconformably overlies Archaean granite-
greenstone basement and comprises about 1,500 m of alternating quartz arenite and shale
typical of the sequence elsewhere in the basin. Central Rand Group strata are less well
developed with the Johannesburg Subgroup, including the Bird amygdaloid and the Booysens
shale, comprising about 300 m. The Turffontein Subgroup is 600 m thick and made up of a
sequence of quartz arenites and conglomerates correlatable with the Elsburg Formation.
The following is the stratigraphic sequence, from top to bottom, for Areas 1-3.
Karoo Sequence rocks are found as cover in large parts of Area 1, however, there are only
minor rocks of the Karoo sequence in Area 2 and no Karoo units have been observed at Area
3. The Karoo rocks are represented by Ecca (EC) sandstones, shales and coal and Dwyka
(DY) tillite and coal. Large areas are covered with Karoo dolerite sills.
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The Ventersdorp Sequence in the deposit area is represented by Ventersdorp sediments, north
of the area at Klein Vankolderskop where the drilling intersected Klipriviersberg Group lavas
(KBG), followed by well-developed Alberton Porphyry Formation (APF) and then the talcose
lava of the Weston Area formation (WF).
The Ventersdorp Contact Reef (VCR) is developed in places and forms the base of the
Ventersdorp Sequence, in places well mineralized with sulphides. In general the VCR
represents a medium – large pebble conglomerate (MPC – LPC) with some inter reef
quartzite. The Speckled Reef Zone (SPR) is more often developed than the VCR and consists
of a small pebble conglomerate (SPC) which is usually very poorly packed and sorted and has
no discernible unconformity with the SCRZ of the Witwatersrand.
The Scattered Reef Zone (SCRZ) of the Brendan Conglomerate Formation consists of the
scattered reef zones set in a green coloured siliceous quartzite. The reefs are usually very
poorly packed and very poorly sorted with occasional sulfide mineralisation. The reefs are
poorly defined with their continuity not known as yet. The average thickness of the SCRZ
from historical and current drilling excluding any holes with structural complications is
approximately 55 m. The SCRZ thins towards the north and east to approximately 20 m, but
towards the south of the drilling area SCRZ of up to 80 m is seen.
The Drab Zone (DZ) of the Kinross Conglomerate Formation is a dark coloured, highly
argillaceous, uniform quartzite. It is gritty in places and usually has a transitional contact with
the underlying Intermediate Zone (IZ). The average thickness of the DZ is approximately 85
m. The DZ also thins towards the north and east.
The Intermediate Zone (IZ) of the Kinross Conglomerate Formation is quartzite that is more
siliceous than the DZ but contains major argillaceous banding. The IZ contains more
abundant gritty zones. The average thickness of the IZ is approximately 90 m. The IZ again
thins towards the north and east.
The Intermediate Reef (IR) of the Kinross Conglomerate Formation is found at the base of the
IZ, it is usually a gritty zone with an associated pyrite rich horizon, it is highly variable and
locally not developed.
The Hanging Wall 1 (HW1) of the Elsburg/Evander Quartzite Formation is a quartzite with
varying character. It varies from very argillaceous to cleaner and siliceous, but in general the
14
HW1 is more siliceous and sericitic than the IZ and easily distinguished from IZ quartzites.
The average thickness of the HW1 is approximately 14 m.
The Leader Reef (LR) of the Elsburg/Evander Quartzite Formation is an underdeveloped zone,
usually consisting of a dark coloured gritty unit or zone of dark coloured grits, but in places it
is not developed at all.
The Hanging Wall 2 (HW2) of the Elsburg/Evander Quartzite Formation also has a varying
character, but it is often differs slightly from the HW1 with less argillaceous material. A grit
marker zone in the hanging wall, similar to the LR, is developed approximately 5 – 7 m above
the top of the reef. In historical work, this unit was often misinterpreted as the LR (Gencor,
Southgold). The average thickness of the HW2 is approximately 44 m. Some thinning of the
HW2 takes place towards the north and east.
The Kimberley Reef of the Elsburg/Evander Quartzite Formation unconformity cuts
downward to north and east of the area, with MK3 quartzites found as the footwall unit,
immediately south of the current drilling area. KS and PUD form the footwall in the central
part of the Burnstone area. MBQ1 and then BA1 occur as the footwall units to the Kimberley
Reef in the northeast.
Puddingstone (PUD) channel deposits, consisting of diamictite and chloritoid shale, are found
in the area, and are younger than the Kimberley Shale and are thought to be an erosional
precursor to the Kimberley Reef.
Kimberley Shale (KS) of the Booysens Shale Formation is black-coloured shale. The unit is
commonly altered near the top, close to the reef, and has a khaki colour.
The Main Bird Quartzite 1 (MBQ1) of the Leandra Quartzite Formation is a very clean
siliceous fuchsitic quartzite. A thin transitional zone with the KS results in a more
argillaceous quartzite at the top.
Bird Amygdaloidal Lava 1 (BA1), tuff and tuffaceous lava occur at the top, followed by
amygdaloidal lava.
A non-magnetic dioritic sill, with an average thickness of a 100 – 105 m, is seen in Areas 1
and 2. The sill starts in the footwall Stratigraphy in the southern parts of Areas 1 and 2, then
15
cuts through the reef (sill break through) to become a hanging wall unit, and shortly thereafter
breaks out to surface.
Between conglomerate dominated reef and the thick quartzite dominated reef, there is an area
that probably represents an environment where longitudinal gravel conglomerate bars formed
preferentially. Such bars are elongated in plan view, and separated from each other by
channels flowing both parallel to the bars, and diagonally across their long dimensions. The
clast-supported gravel bars probably formed along the sides of high-energy streams and at
places where the flow depth changed. This area, characterized by a relative abundance of
clast- and matrix supported conglomerate units within the reef profile, is thought to have the
best potential for economic gold concentrations. Other conglomerate facies also have the
potential to be auriferous as well. In general, gold concentration decreases with a decrease in
packing density of conglomerates, as well as an increase in the number of sandy litho-facies
within the vertical profile.
The channel width diagram suggests a channel direction of from northeast to southwest in
Area 1 and 2. A possible explanation is that the regional drainage was in a southwesterly
direction and other streams joined the main stream from a more northwesterly direction, as
observed in the channel width diagram.
b. Structure The South Rand gold field is displaced by a number of large east – west-trending faults, which
were originally probably of reverse attitude. The northern limit of the gold field is defined by
the Sugarbush fault, which is down-thrown to the south of up to 3,000 m, and is largely
responsible for the preservation of the Witwatersrand strata in this region (Pretorius 1964).
Sediments of the West Rand Group and Central Rand Group were also deformed prior to
Ventersdorp deposition. The South Rand area currently defines an arcuate sub-outcrop pattern
known as the Balfour synform, which is concave to the north.
Geological interpretation from the recent Great Basin drilling, combined with a detailed
review of the historical data, indicates that the Burnstone deposits are cut by a number of
northwest to east-west trending faults that are down-thrown on their northeast side (Figure
7.4). The shallow block on the southwest side of Area 1 positions the Kimberley Reef within
250 m of surface. The down-thrown block on the northeast flank of Area 1 has resulted in the
Kimberley Reef being situated at approximately 1,000 m from surface in that area. Structural
contours of the Kimberley Reef also indicate that although Area 1 is located on a regional
broad antiform, it consists primarily of shallow north and south dipping fault blocks.
16
B
B’A
A’
C
C’
Figure 7.4. Burnstone Gold Deposit-Areas and Major Faults
The structure of Areas 1 – 3 is dominated by the Sugarbush fault in the north, and associated
faults (i.e. Step 1 and 2 faults). The southerly dipping listric Sugarbush fault bounds the
deposit areas in the north. Basement granites and lower Witwatersrand group rocks are found
north of the fault. The Step 1 and 2 faults are steeply northerly dipping (approximately 80 )
faults with a combined displacement of over 550 m. The faults can be traced through Areas 1
and 2. Several splays from the Step 1 and 2 faults, with throws of up to 100 m, are found in
Areas 1 and 2 (for example, there is a cross fault in Area 1 and the splays in the vicinity of
drill holes SGG081, SGG052 and 1950 in Area 2). Minor north – south faults (for example,
the Darby fault) are also present.
Several shallow horst blocks, with Witwatersrand rocks exposed at surface, are located south
of the step faults in the center of the study area. The Kimberley Reef occurs at depths of 250
– 450 m below surface in a wide zone extending from Area 1 and 4 to Area 3. It is bound in
17
the south by southerly dipping faults with varying displacements. This horst and graben effect
is similar to what is seen in the Free State and Klerksdorp Goldfields.
An anticlinal feature is present on the shallow horst block in Areas 1 and 2. The anticline is
associated with the sill break out; the anticlinal feature is accentuated by the apparent thrusting
along the break out. The break out probably occurs as the plain of weakness along the fold
axis of the very gentle anticline.
Several intrusions have been observed in drill holes and have also been interpreted from the
aero magnetic map. North-south magnetic dykes are found between Areas 1 and 2. East -
west trending dykes are present in Areas 2 and 3.
Evidence of left lateral movement has been seen from displacement of quartz diorite dykes.
The lateral movement has been used in interpreting grade distribution in Area 2 with some
success.
Great Basin commissioned a structural mapping program that was carried out from January to
April 2004, revealing two structural elements that strongly influence the distribution of rock in
the Burnstone project area (Oliver, 2004; see Regional Geology Map in Illustrations at the
back of the report). A regional horst elevates the rock units in the central portion of the
Burnstone property to shallow depths. The horst is formed through the development of west-
northwest trending faults, the dip direction of which reverses from south, along the southern
boundary to north the along the northern boundary. The width of the horst narrows to the
southeast, and broadens to the northwest. This flaring of the horst is caused by the divergence
in strike direction between the north and south bounding faults. These faults may converge
southeast of the property boundary.
Across 14 km of sectional width, 14 fault structures were mapped. Of these 14 structures, 12
are sinistral trans-tensional faults. Only two are likely to be dextral.
Within this structural regime, west-northwest trending structures are linked by arcuate,
sigmoidal extension zones, commonly east-west in their orientation. These structures have,
commonly, been in-filled by later dolerite dykes. There is no evidence from surface
geological data for the presence of low angle thrust duplexes and stratigraphic shortening or
contraction. The overall structural environment is dominated by sinistral, trans-tensional
faults. Offsets of sub-vertical, planar, quartz diorite dykes provide the most reliable estimates
18
of translational offsets. Offsets of folded volcanic contacts, particularly in the North Witpoort
area (Area 3) may result in conflicting movement histories.
The stratigraphy has also been elevated and depressed, locally, by the presence of regional
synform-antiform couples. These folds migrate and change in intensity relative to their
distance from the northern border faults, and to their proximity to basement and lower
Witwatersrand successions. Closer to northern bounding faults, the folds are characterized by
short steep limbs, and long flat limbs. Farther from the major northern bounding faults, the
stratigraphic section occurs within gentle, open, antiform-synform couples.
Some evidence exists for stratigraphic thinning across the crest of the major antiform, which
transects the central portions of the Burnstone property. This west-northwest trending
structural feature may have been present at the time of sedimentation.
The upper contact of the Alberton Porphyry is one of the most useful regional assessments of
the depth to the top of the VCR and Scattered Reef Zone. These rocks will typically lie
approximately 150 – 180 m below this contact. The KR occurs 300 – 420 m below the VCR.
The contact provides an excellent lithologic marker to screen basement highs.
c. Footwall Geology The lithology of the footwall to the Kimberley Reef varies across the entire project area. The
Kimberley Shale forms the footwall to the reef in the central part of the project area and forms
the greatest portion of the footwall lithologies in the area investigated to date. Laterally, the
unconformity exposes successively higher stratigraphic units to the southwest, representing
less extensive erosion across the unconformity surface. To the northeast, the unconformity
exposes older stratigraphic units, representing uplift to the northeast (Devon Dome) during
Kimberley Reef deposition.
d. Sedimentology In the Burnstone area, the Kimberley Reef is generally an upward fining, quartz pebble
auriferous conglomerate that was probably deposited within a braided river environment. It
overlies a major unconformity at the base of the Evander Quartzite Formation, part of the
Turffontein Subgroup of the Central Rand Group.
Nature of the Unconformity The Kimberley Reef occurs on a major angular unconformity, which correlates with the
unconformity that occurs at the base of the GE8A Unit in the Klerksdorp Goldfield across the
19
Witwatersrand Basin as well as the unconformity at the base of Big Pebble Reef - 6A Reef
within the northern Free State Goldfields (Target – Sun Areas).
The Kimberley Reef unconformity resulted from a regressive truncation of the footwall from
southwest to northeast. Within the Burnstone area, the MK3 Quartzite, Booysens Shale
Formation, Main Bird Quartzite 1 (MBQ1) and Bird Amygdaloid (BA1) are progressively
truncated to the northeast by the unconformity.
This progressive erosion of the footwall units to Kimberley Reef also affected the
Puddingstone Unit. The Puddingstone represents a major erosion event that pre-dates the
unconformity. Below the unconformity, the subcrops of the footwall units generally strike
northwest – southeast. As only surface borehole data is available, it is assumed that the
palaeo-surface is relatively flat.
Lithology of the Kimberley Reef
In the Burnstone area, the Kimberley Reef may generally be described as:
Poorly sorted,
Sub-rounded,
Clast to matrix supported,
With a maximum pebble size generally within the very coarse pebble size range, i.e.
from 32 to 64 mm,
The matrix can vary from siliceous to argillaceous, with some sericite and chlorite,
Pebble types are predominantly white quartz, lesser smoky quartz, minor chert and in
places, blue quartz, quartzite, shale rip-up clasts (Booysens Shale Formation), and
acidic lavas,
Pyrite, both crystalline and buckshot (generally rare), and carbon may be present, and
Visible gold has been noted in a high proportion of intersections.
Visible gold has been noted throughout the project area in the Kimberley Reef in a number of
differing settings: in conglomerate with an argillaceous/siliceous matrix, in the
presence/absence of carbon and pyrite/sulphides, and in places, where no pyrite or carbon has
been observed within the conglomerate, within sandy conglomerate and diamictite footwall.
Reef Types / Reef Definition
The Kimberley Reef displays considerable variation, both vertically and laterally as can be
expected in a braided river environment. A broadly defined interpretation that has not yet
20
been fully quantified is proposed. The overall Kimberley Reef package generally fines
upward, and contains minor quartzite components.
In general, the Kimberley Reef is a robust conglomerate, with subordinate gritty/pebbly
quartzite units, that exhibits a remarkable degree of geological continuity over the project area.
The thickness of the Reef can vary from 2 – 3 cm (pebble lag) to over 100 cm (channel reef
types). The base of the Reef is always sharp, i.e. well distinguished from the underlying
lithology. The footwall to the Kimberley Reef is one of the following: MK3 Quartzite,
Booysens Shale Formation, Puddingstone Unit, MBQ1 or Bird Amygdaloid (BA1). Usually,
the top of the Reef is defined by the top of the conglomerate unit but in some cases, the top is
defined by the Kimberley Reef Quartzite, which is, lithologically, distinct from the Hanging
Wall 2 quartzites. In some cases, a diffuse top contact has been observed, and is thought to be
the result of the development of either a pebbly or gritty quartzite unit on top of the
conglomerate. This quartzite is not always distinct from the Hanging Wall 2 quartzites. The
dominant component of the Kimberley Reef is conglomerate, with lesser quartzite.
Sedimentological Model
Though not fully quantified, the Kimberley Reef is interpreted having been deposited in three
distinct settings:
Thin Conglomerate/Pebble Lag Kimberley Reef, that occurs to the northeast and
along the northeast margins of the Burnstone property; palaeo-current directions
indicate it was deposited from the northeast;
Clast and Matrix supported conglomerate, that occurs in the zone of Area 1 and 2 of
the Burnstone property with an interpreted current direction from the northeast, and
Channel Type Conglomerate Kimberley Reef containing both conglomerate and
quartzite, that occurs along the south-southwest portions of the Burnstone property,
with indicated palaeo-current directions from northwest to southeast.
8. EXPLORATION
a. 2003 Program A regional aeromagnetic survey was flown in late 2002 and made up the bulk of the Phase I
exploration program. The structural interpretation from this survey has greatly assisted in
identifying structural discontinuities affecting the project area.
21
Three phases of drilling – Exploration phases II, III and IV - were conducted in 2003.
Geosearch (Pty) Limited of South Africa carried out the drilling programs, with 101 drill holes
completed.
Phase II drilling was concentrated primarily in Area 1. Drill holes SGG001 through SGG040
as well as 45 and 47, totalling 32,526 m of NQ diameter core (4.76 cm) and lesser quantities
of BQ diameter core (3.64 cm) in primary boreholes and deflections, were drilled. The drilling
was designed to decrease the inter-borehole distances to a spacing of approximately 350 m.
Phase III and Phase IV drilling was focused more on Areas 2 and 3, with the objective of
increasing the understanding of the geological and sedimentological features of these areas as
well as moving towards outlining mineral resources. Approximately 26,671 m in primary
holes and deflections were drilled during this phase. The holes drilled were SGG041 to
SGG080, with the exception of holes 45 and 47.
Subsequent drilling in 2003, still as part of the Phase III and Phase IV exploration programs
targeted Areas 1, 2 and 3. During this phase, an additional 5,996 m in primary holes and
deflections were drilled, including holes SGG081 through to SGG101. Refer to Figure D –
SGG boreholes localities and Areas 1, 2, and 3.
b. 2004 Program Exploration Phase V continued the drill program in Areas 1, 2 and 3 and initiated drilling in
Area 4. An additional 33 holes totalling 21,630 metres have been drilled in Areas 1, 2, 3 and
4 from January 2004 to April 30, 2004. The 2004 holes consist of a primary hole along with
an average of 5 deflections. The purpose of the two additional deflections was to provide
samples for mining and metallurgical studies. The purpose of holes drilled in Area 1 was to
infill areas for additional information and to drill across (using inclined holes) the major faults
in the area to better understand the nature and mechanics of structural complications. Holes in
Area 2 and 3 were to continue to outline the area of economic mineralization within the
Kimberley Reef in those areas. Drilling in Area 4 was initiated to evaluate the continuous
nature of the Kimberley Reef from Area 1 into the down-dip extensions in Area 4.
Kimberley Reef Stratigraphy and Mineralisation
Area 1See Cross Section A-A’ in Illustrations at the back of the report (section location is shown on Figure 7.4); analytical results are summarized in the Area 1 tables in Appendix A.
22
Area 1 consists primarily of younger Ventersdorp Supergroup volcanic material
unconformably overlying the Central Rand Group sediments of the Witwatersrand
Supergroup. The Ventersdorp Contact Reef (VCR) located at the base of the volcanics was
also intersected in numerous drill holes and sampled for its gold content. However the VCR
was found to be of low grade or barren of gold.
The Kimberley Reef unconformably overlies the Puddingstone, Kimberley Shale and Main
Bird Quartzites, indicating that erosion has down-cut into the older stratigraphy, progressively,
from southwest to northeast.
The Kimberley Reef conglomerate is variable in terms of its pebble size, degree of sorting,
and mineralogical composition. These variations are a function of the environment of
deposition (braided river environment), the nature of the source area supplying detritus, and
the extent to which later hydrothermal or metamorphic fluids have passed through the reefs.
Typically, the Kimberley Reef comprises between 70 and 90 % well-rounded pebbles, made
up predominantly of milky vein quartz together with lesser chert, blue quartz, jasper, quartzite,
shale and other rock fragments. Pebbles are cemented in a matrix of finer, more angular quartz
grains and a variety of phyllo-silicate minerals including sericite, pyrophyllite, muscovite,
chlorite and chloritoid.
A mineralogical investigation revealed that gold grains were present in many of the analysed
samples reflecting the high gold values exhibited by some of the samples. The matrix of these
gold-bearing conglomeratic reefs is uncharacteristically low in sulphides and other heavy
mineral components, especially considering that some of them contain the high gold values.
Overall, all samples studied displayed similar mineralogical characteristics. Quartz is the
dominant phase and the matrix minerals are predominantly chlorite, mica and apatite.
Uraninite and pyrobitumen (kerogen) was observed indicating possible correlation with higher
gold grades.
Area 2See Cross Section B-B’ in Illustrations at the back of this report (section location is shown on Figure 7.4); analytical results summarized in the Area 2 tables in Appendix A.
Visible gold has been observed within the Kimberley Reef conglomerate in approximately
50% the drill holes from Area 2, and the gold appears to be more coarse-grained than that of
Area 1 boreholes. Most of the drilling in Area 2 has intersected a thicker Kimberley Reef
horizon that contains more quartzite material. Predominantly, Puddingstone and Kimberley
Shale, form the footwall of the Kimberley Reef in Area 2.
23
Area 3See Cross Section C-C’ in Illustrations at the back of this report (section location is shown on Figure 7.4); analytical results are summarized in the Area 3 tables in Appendix A.
More abundant nodular carbon has been noted in the Kimberley Reef conglomerate in Area 3.
This is often associated with abundant visible gold and pyritic sands, particularly when the
footwall is comprised of the MBQ1 quartzite unit. There is a considerable variation in reef
types between various deflections from a single borehole in Area 3. In addition, the quartzite
component can be considerably higher than the amount of conglomerate in the Kimberley
Reef package.
9. Sampling Method and Approach One hundred and one holes, totalling 65,193 m of NQ core (4.76 cm diameter) and BQ core
(3.64 cm diameter) were completed in primary boreholes and deflections during the 2003
program. An average of three deflections were drilled from each primary hole, to increase the
sampling of the Kimberley Reef in each location. An additional 33 holes, totalling 21,630
metres, have been drilled in Areas 1, 2, 3 and 4 from January 2004 to April 30, 2004. The
2004 holes consist of a primary hole along with an average of 5 deflections. The purpose of
the two additional deflections was to provide samples for mining and metallurgical studies.
Drill core was boxed at the drill and shipped daily to the secure logging facility at Balfour.
There the drill core was photographed, geologically logged and selectively sampled. Digital
photograph images were taken of each box of core and were archived on CD-ROM. Core
recovery was generally very good, averaging 99.8% for the sampled intervals.
Information recorded in the sample logs included: drill hole I.D., from (m), to (m), core angle,
recovery, sample number, core size, completeness code, representative (yes/no), status
(complete/incomplete), use (yes/no), stratigraphy code, lithology code and general comments.
In addition to this specific gravity measurements were taken from sampled intervals of
Kimberley reef and surrounding wall rock.
The minimum length proscribed for reef samples was 15 cm of core (approximately 250 g).
To ensure that the reef intersection was cut into two equal halves without bias, a cut-line was
marked at the low point of the bedding plane of the base of the reef. Depending on the core
angle at the base of the reef intersection, a maximum of 2 to 3 cm and a minimum of 1 cm of
the footwall rocks were also included in the basal sample of the reef. Two samples were taken
above and below the reef intersection as follows:
24
Hanging Wall
Sample immediately above reef is +/- 25 cm in length
Uppermost sample is +/- 25 cm in length.
Foot Wall
Sample immediately below the reef is +/- 25 cm in length
Lowermost sample is +/- 25 cm in length.
In addition to the regular mainstream samples, quality assurance/quality control (QA/QC)
samples were inserted into the reef sample stream. These included: blank samples (half core
from the overlying Au-barren drab quartzite) and standards (pulps) inserted as a check on lab
accuracy. The analytical laboratory was unaware of the identity of the QA/QC samples. If the
value for a standard or a blank was not within acceptable limits the sample lot was reassayed.
10. Sample Preparation, Analysis and Security A drill core sampling and analytical flow diagram is attached as Figure 10.1.
Samples were taken by sawing the core in half lengthwise with a diamond-tipped blade. With
the base of the reef dipping away from the sampler, the top half cores are always submitted for
assay. This ensures consistency and unbiased sampling procedures. The samples were placed
in bags and sealed with numbered “Pull-Tite” chain-of-custody security seals and stored in a
locked and secured building prior to being delivered to the analytical laboratory. The
remaining half core was returned to the core boxes and stored at the Balfour warehouse.
25
Figure 10.1 Flow Sheet of Sampling and Analytical Process
NQ Core Sample
(4.76 cm diameter) +/- 20 cm Length
½ CoreRemainder
+/- 400 g
Coarse Sample e.g. 5040
½ Core
Original Split
DRILLING:by Geosearch,
Cores Transported
by Geosearch from
Drill Site to SouthGold Facility
at Balfour
LOGGING:Logged and Sampled
by Geoactiv at
Balfour Facility
SAMPLE PREPARATION: Prepared at SGS
Lakefield
Laboratory Johannesburg South Africa
SHIPPING:½ Core Samples
Transported to SGS
Lakefield Research Africa (Pty) Limited
Laboratory Johannesburg South
Africa
ANALYSIS:
at SGS Lakefield Au
by Triplicate 50g Lead Collection Fire Assay with AAS or Grav. (if High), Ag by AAS, S
by LECO, U308 by
XRF, for some samples Trace
Elements by Total Digestion ICP-OES
finish.
Core Sawn in Half
Stored at SouthGold Warehouse
Balfour South
Africa
Entire Sample Dried,
Crushed to 70% < 2 mm
(10 mesh)
Entire Sample Pulverized to 95%
< 75 micron
Project & Commercial
Standards
Blind Standard Inserted
Immediately Above Last Reef Sample
+/-400 g Regular Pulp
e.g. 5040
+/-200 g Pulp
Reject
Au Standarde.g. 5039
STD 98GV3
Photographs Archived on CD
Core Photography
Inserted After any Visible Gold Sample or After Last
Reef SampleCoarse Blank (Drab
Quartzite) e.g. 5041
Selected Duplicates Incl. all Au Results > 5.0 g/t
SHIPPING:Duplicate Pulp
Samples Shipped by
Air Freight to Acme
Analytical Laboratory,
Vancouver, Canada
Check
Assay
Acme
50 g Au
Assay
"A"
50 g Au
Assay
"B"
50 g Au
Assay "C"
Au Result Average of Triplicate FA Fusions A B C50 g FA Fusion
Approximately
10% of Duplicates
Stored at SGS Lakefield or Acme
26
11. ADJACENT PROPERTIES The Evander goldfield is located approximately 120 km east of Johannesburg. The principal
economic horizon is the Kimberley Reef, which was deposited in a subsidiary sedimentary
basin contemporaneous with the early stages of the Turffontein Subgroup of the Central Rand
Group.
A series of basin subsidence and uplift phases resulted in the deposition of several
sedimentary sequences. Later, erosion of the elevated basin-margin resulted in the deposition
of the Kimberley Reef in a network of braided channels. Major faulting and dislocation
occurred as well as a final tectonic event, involving a tilting of the whole basin 8 to 10º to the
north in post-Transvaal times.
The Kimberley Reef represents the distal facies of a fluvial placer that was deposited by a
system of braided-streams, which flowed down a northeasterly dipping palaeoslope. The reef
is oligomictic and comprises a composite sequence of channel-sediments that define
longitudinal gravel bars and sand bars with pebbly veneers. Multi-channeling is well
developed in areas where the reef is thick (Figure 11.1).
Figure 11.1. Kimberley Reef Morphology at Evander Goldfield (Tweedie, 1986)
The Central Rand Group in the Evander goldfield comprises a composite sequence of
interbedded conglomeratic and non-conglomeratic quartzites that average 650 m in thickness.
The sequence is very thin at Evander when compared to the western part of the
27
Witwatersrand. Interbedded within this sedimentary pile are two andesitic lava units, and the
Kimberley Shale is the only argillite present (Tweedie, 1968). Many of the units occurring
below the Kimberley Reef are lithologically very similar to those occurring at a similar
stratigraphic position in the East Rand Basin.
The Kimberley Reef rests on a well-defined angular unconformity, which is responsible for a
cut-down in a southwesterly direction of approximately 200 km of footwall stratigraphy. The
Kimberley Reef was deposited during a regressive truncation of the footwall-beds, as a result
of tectonic uplift to the southwest, with progressively older beds underlying the reef higher up
the palaeoslope. Hence, it is only along the eastern margin of the basin that the thickest
footwall succession is preserved. Eventually, the Kimberley Reef is, itself, truncated and sub-
outcrops beneath Karoo sediments along the southern and western margins of the basin.
The Kimberley Reef at Evander is a quartz pebble conglomerate orebody that is characterized
by an abundance of pebbles and conglomeratic layers, interbedded with subordinate quartzite
units. Harmony Gold has provided Great Basin’s geologists and South African contractors
with the opportunity to examine the pebble conglomerate Kimberley Reef in the Evander mine
in detail along with geological discussions of Reef formation and economic evaluations.
Examples of the reef examined include an auriferous, 10 cm thick single conglomerate
horizon as well as a 1.5 m thick interval of the reef that contains up to three 15-20 cm thick
horizons of quartz pebble conglomerate. Textures and structures observed in the course of the
drill program at Burnstone were near identical to those observed in the mining faces at
Evander. The mine tours at Evander greatly aided in the visualization and interpretation of the
Kimberley Reef horizon that was intersected during drilling at Burnstone.
Gold within the Kimberley Reef occurs as minute, free particles in the matrix and also as
inclusions within compact detrital pyrite (Hallbauer et al., 1978). The average grade of the
reef, taken over 25 years of production, is indicated to be 8.56 g/t, and the ratio of this grade to
the mean grade for the whole Witwatersrand Basin is 0.92.
The pattern exhibited by the gold isocons across the Evander Basin correlates very well with
the regional dispersion or drainage pattern defined by reef isopachs. Well-developed, linear,
gold-value trends are directed towards the north-west, north, north-east, east and south-east.
Many of these split and re-unite in a manner very similar to the channel trends defined by reef
isopachs.
28
The correlation between gold-value trends (Figure 11.2) and the axis of inferred Kimberley
Reef channels (Figure 11.3) is good, with the paucity of sand filled channels enhancing this
correlation. The axes of channels and high value trends are not necessarily coincidental, as
this factor depends on the physical properties of each channel. This is compounded by the
fact that these major channels are not single units, but comprised of an ordered hierarchy of
channels and bars of varying orders of magnitude. The most important conclusion to be
drawn is the high degree of parallelism between the channel and the value trends. Although
the correlation between thickness isopachs and gold isocons is generally good, areas of poor
correlation do exist.
Figure 11.2 Gold Isocons In the Kimberley Reef - Evander Goldfield (Tweedie, 1986)
29
Figure 11.3 Kimberley Reef Channel Development – Evander Goldfield (Tweedie, 1986)
12. MINERAL RESOURCE ESTIMATES
For details of resource estimates for Area 1, see the “Report on the June 2003 Resource
Estimate for Area 1 of the Burnstone property, Mpumalanga Province of the Republic of
South Africa” by James A. Currie, P.Eng., Behre Dolbear & Company, July 2003. An
updated Resource Estimate for Area 1 and a Resource Estimate for Area 2 will be published in
about 1 months’ time.
30
13. INTERPRETATION AND CONCLUSIONS It can be concluded that after 15 months of drilling and data collection, an excellent
understanding exists pertaining to the geology, sedimentology and structure of the Burnstone
Gold Project area. The geological and exploration models developed thus far will only
improve with more drilling, surface mapping and general geological data collection during
2004.
Geological and analytical data collection and manipulation have been carried-out in a very
professional and efficient manner.
14. RECOMMENDATIONS Based on the detailed drilling and compilation, there is an excellent understanding of the
geology, sedimentology and structure of the Burnstone project area, particularly Area 1. It is
recommended that additional drilling be carried out in Areas 2, 3 and 4, as well as surface
mapping and general geological compilation work, to improve the geological and exploration
models developed so far and to test the land that has been added to the project area since
beginning of 2003, including:
collation of all available geological data to date to define/refine the current tectono-
sedimentary exploration model as well as refine targets to optimise future drilling
programs;
continuation drilling Areas 2, 3 and 4 to test and delineate potential mineralised shoots
and decrease the inter-borehole spacing in order to increase geological and geo-
statistical confidence levels;
continuation the surface mapping program with particular emphasis on recording
stratigraphy and structure; and
consolidation of the existing property databases for additional properties acquired.
The proposed budget provides for drilling of 40,000m of NQ core in Areas 1, 2, 3 and 4. The
40,000 m drill program provides for the definition and delineation of the Kimberley Reef
(sedimentology, grade and thickness) in the four areas as well as drill holes for engineering
purposes (location and nature of faulted areas, metallurgical samples and rock strength tests).
The budget provides for the geological staff (wages and expenses) required to document and
interpret the data obtained and for the sampling and analysis of the intersections obtained. It
also provides for Sedimentology studies and Resource Calculation consultants. Technical
31
graphics will be done on site and the budget provides for these costs (wages etc) and
acquisition of the required hardware.
Mine contractors have been engaged to conduct an updated assessment of the mine plan and
mining costs based on the recent resource estimate and grade model. They will then progress
into the Prefeasibility study for the twin decline option complete with capital and operating
costs to 15%. The contractor will also address the project power requirements including
sources and costs for power, substation/transformer sizing and costing and power distribution.
Metallurgical test work for gravity and leach tests is currently underway. An RSA consultant
will be engaged to provide a process plant flow sheet and general arrangement, and capital and
operating costs.
Pertinent contractors will provide an overview of the environmental risks including surface
and groundwater, air, noise, dust, and visual impacts for all phases of the project. This same
contractor will also address options for disposal of tailings including identification of mill
sites and tailings sites, and capital and operating costs associated with tailings disposal.
Included will be the costs of tailings delivery to the impoundment facility, and water reclaim
back to the mill.
An independent contractor will address the project permitting requirements and permitting
timelines.
The proposed budget required for the continuation of the above investigations is as follows:
Field Costs $CDN
(note: converted from rand at R5.25 = $1CDN)
Assays and Analysis
Assays and Analysis $86,333 Verification Contractors $14,648
Drilling
Diamond Drilling (36,000m) $2,7422,857 Bottom Hole Deflections (4,000m) $304,762 Engineering
Project Engineering $226,350 Consultant Reports/Resource Calculations $50,476 Scoping/Prefeasibility Studies $321,905 Enviromental
Environmental Studies $14,286 Lands/Permitting $54,954 Equipment Rentals/Leases $3,810
32
Geological
Geological Consultants (GeoActiv) $352,381 Geodata Handling $15,238 Geological Salaries $265,714 Surveyor/Data Acquisition $23,810 Freight $5,333 Database Management and Graphics
Draughting Wages $49,524 Graphics Supplies $14,286 Site Activities Field Supplies $12,381 Room and Board $53,333 Site and Equipment Fuel $21,905 Site Rentals (Vehicles) $15,238
Telephone/Fax $11,429 Mineral Farms/Fees $29,524
Travel $142,857Total Field Costs $4,833,333
15. REFERENCES Antrobus, E.S.A., (1986). The South Rand Goldfield. In: Mineral Deposits of Southern
Africa, I (C.R. Anhaeusser and S. Maske, eds.): Geological Society of South Africa,
Johannesburg, p. 698 – 703.
Currie, James A., (2003). Report on the June 2003 Resource Estimate for Area 1 of the
Burnstone property, Mpumalanga Province of the Republic of South Africa, Behre Dolbear &
Company, July 2003, Technical Report prepared for Great Basin Gold Ltd.
De Jager, F.S.J., (1986). The South Rand Goldfield. In: Witwatersrand Gold – 100 Years
(E.S.A. Antrobus, ed.): Geological Society of South Africa, Johannesburg, 167 – 172.
GeoActiv (Pty) Ltd (2002). Geological Report on the Burnstone Gold Project, appended to
Rance, Derek C., (2002). Qualifying Report on the Burnstone Property, Gauteng Province of
the Republic of South Africa, Behre Dolbear & Company Ltd, November 28, 2002. Technical
Report prepared for Great Basin Gold Ltd.
Oliver, J.L. (2004). Structural and Stratigraphic Relationships of the East Witwatersrand
Basin, Burnstone Gold Project, Mpumalanga Province, South Africa. Internal Report for Great
Basin Gold Ltd.
Pretorius, D.A. (1964). The geology of the South Rand Goldfield. In: Geology of some ore
deposits in Southern Africa, 1. (S.H. Haughton, ed.): Geological Society of South Africa,
Johannesburg. 219 – 282.
Tweedie, E.B. 1978. History, geology and value distribution of the Evander Goldfield,
Eastern Transvaal, South Africa, Proc. 11th Min. Metall. Congr, 23. 8pp.
Tweedie, E.B. 1986. The Evander Goldfield. Mineral Deposit of South Africa, pp705-730.
33
16. DATE The date of this report is May 19, 2004.
17. CERTIFICATES
34
Daniel B. Kilby, P.Eng. [email protected]
I, Daniel B. Kilby, of 718 East Fourth Street, North Vancouver, British Columbia hereby certify that:
1. I am an employee of Hunter Dickinson Inc, with a business office at Suite 1020-800 West Pender Street, Vancouver, British Columbia. Hunter Dickinson Inc., on behalf of Great Basin Gold Ltd., contracted my services to carry out and supervise exploration programs on Burnstone Gold Project, South Africa in 2003 and 2004.
1. I am a graduate of the University of British Columbia (B.A.Sc., Geological Engineering, date 1971).
2. I have practiced my profession continuously since graduation and have been involved in and managed exploration projects internationally, including mineral deposit resources delineation and evaluation in Canada, United States of America, Mexico and South Africa.
3. I am a member in good standing of the Association of Professional Engineers and Geoscientists of British Columbia, registration number 14283.
4. As a result of my experience and qualifications, I am a Qualified Person as defined under National Instrument 43-101.
5. I have visited the Burnstone property and supervised drilling programs at site in 2003 and 2004. I was on site during the periods of January to December 2003, and January to April 2004. I am familiar with the geology, topography, physical features, access and local infrastructure.
6. I am not aware of any material fact or change with respect to the subject matter of this Report, which is not reflected in the Report, and the omission of which would make the Report misleading.
7. I have read National Instrument 43-101. 8. I consent to the use of this Technical Report for disclosure purposes of Great Basin Gold
Ltd.
Signed at Heildelburg, Gauteng, South Africa on the 19th day of May, 2004.
“Daniel B. Kilby” __________________________ Daniel B. Kilby, B.A.Sc., P.Eng.
35
G. Robert Cluff, BSc(Hons), MSc [email protected]
I, G. Robert Cluff, of 8089 158A Street, Surrey, British Columbia hereby certify that:
9. I am an employee of Hunter Dickinson Inc, with a business office at Suite 1020-800 West Pender Street, Vancouver, British Columbia. I was employed by Hunter Dickinson Inc., on behalf of Great Basin Gold Ltd., to carry out exploration programs on Burnstone Gold Project, South Africa in 2003 and 2004.
10. I am a graduate of the University of Saskatchewan, Saskatoon Campus, with the degrees B.Sc.(Hons), date 1974 and M.Sc., date 1981.
11. I have practiced my profession continuously since graduation and have been involved in and managed exploration projects internationally, including mineral deposit resources delineation and evaluation in Canada, United States of America, Mexico and South Africa.
12. I have visited the Burnstone property and supervised drilling programs at site during 2003 and 2004. I was on site at individual intervals of up to 30 days a time during the periods of January to December 2003, and January to April 2004. I am familiar with the geology, topography, physical features, access and local infrastructure.
13. I am not aware of any material fact or change with respect to the subject matter of this Report, which is not reflected in the Report, and the omission of which would make the Report misleading.
14. I have read National Instrument 43-101.
15. I consent to the use of this Technical Report for disclosure purposes of Great Basin Gold Ltd.
Signed at Vancouver, BC on the 19th day of May, 2004.
“G. Robert Cluff” _______________________________________ G. Robert Cluff, B.Sc.(Hons), M.Sc.
36
APPENDIX A
SUMMARY OF ANALYTICAL RESULTS – DRILLING IN AREAS 1,2,3
37
Great Basin Gold Ltd.
Burnstone Project
AREA 1 - All Drill Hole Results (True Widths)
Hole
Number
From
(metres)
To
(metres)
Intercept
(cm)
Gold
(g/t)
Thickness
x Grade
(cmg/t)
1127 540.88 541.15 27.4 18.54 508
1687 936.66 937.02 36.3 6.22 226
1688 213.47 213.75 27.6 9.37 258
1774 725.40 725.63 22.7 14.88 338
1843 243.50 243.97 47.1 38.65 1819
1877 849.89 850.03 14.2 12.82 182
1890 1297.86 1298.00 14.3 17.02 243
2510 310.65 311.29 64.1 9.53 611
2531 874.53 874.72 18.8 0.74 14
2626 365.43 365.68 24.6 55.16 1357
2671 444.10 444.52 41.7 2.21 92
2693 684.97 685.81 84.3 5.02 423
2725 401.13 401.32 18.8 7.55 142
2729 243.10 243.72 61.8 19.63 1213
2730 781.71 781.96 24.9 30.54 760
2732 750.36 750.72 36.0 3.06 110
2734 230.00 230.03 2.5 1.32 3
2744 199.49 199.85 35.5 0.89 32
2755 273.33 273.81 47.5 16.35 776
2757 213.10 213.37 27.3 12.03 329
2767 626.06 626.65 58.8 11.03 648
2772 611.82 612.50 68.2 3.38 231
2773 325.73 325.97 23.5 12.15 285
2785 625.94 626.21 27.4 3.34 91
2789 1034.21 1034.44 22.7 9.57 217
2791 415.57 415.85 27.8 12.08 335
2809 469.92 470.11 19.3 1.23 24
2811 939.75 940.07 31.5 53.64 1691
852 874.68 875.02 34.2 67.67 2314
879 677.40 677.62 21.8 8.97 195
SG11 310.40 310.58 17.8 18.35 327
SG12 397.63 397.87 24.2 2.53 61
SG16 393.28 393.54 26.0 4.53 118
SG17 370.56 371.04 48.1 4.30 206
SG4 340.07 340.22 14.9 0.39 6
SG5 271.55 271.78 22.9 27.89 638
SG6 282.18 282.85 67.3 4.84 326
SG7 508.35 508.55 19.6 18.00 353
HIS
TO
RIC
AL
HO
LE
S
38
Great Basin Gold Ltd.
Burnstone Project
AREA 1 - All Drill Hole Results (True Widths)
Hole
Number
From
(metres)
To
(metres)
Intercept
(cm)
Gold
(g/t)
Thickness
x Grade
(cmg/t)
SGG001 577.63 577.87 24.3 18.34 446
SGG002 581.56 581.68 12.4 0.06 1
SGG005 391.42 391.60 17.6 42.95 756
SGG006 526.60 526.76 15.8 6.11 97
SGG007 305.94 306.31 37.0 18.65 690
SGG008 589.04 589.97 92.8 21.11 1960
SGG010 338.84 339.09 25.0 9.41 235
SGG014 340.77 340.97 20.0 2.35 47
SGG015 231.02 231.33 30.6 3.01 92
SGG017 642.18 642.78 59.8 25.83 1543
SGG019 250.13 250.26 13.1 0.81 11
SGG020 213.36 213.69 32.6 2.05 67
SGG022 785.48 786.12 63.8 4.13 263
SGG023 1046.68 1046.86 18.3 2.13 39
SGG024 950.60 950.71 10.9 2.34 26
SGG025 736.41 736.55 14.3 3.81 54
SGG026 557.53 557.97 44.4 10.11 449
SGG028 708.51 708.76 24.7 9.77 242
SGG030 716.38 716.90 51.7 16.11 833
SGG031 583.57 583.72 14.8 2.34 35
SGG033 952.49 952.74 25.1 14.06 353
SGG034 831.63 831.78 15.1 2.10 32
SGG035 647.94 648.30 36.1 0.23 8
SGG036 627.14 627.26 12.3 22.11 273
SGG037 715.83 715.95 12.3 0.58 7
SGG038 774.20 774.34 14.2 5.59 79
SGG039 573.86 573.99 13.2 5.52 73
SGG040 998.50 998.96 46.1 8.15 375
SGG045 631.51 631.93 42.0 6.23 262
SGG047 314.23 314.42 18.7 5.13 96
SGG088 384.02 384.45 43.2 1.15 49
SGG097 415.44 415.76 32.1 18.52 594
SGG106 304.52 304.76 23.5 7.06 166
SGG108 344.79 344.95 16.3 45.24 738
SGG111 333.62 334.09 46.6 2.41 112
SGG113 407.59 407.87 28.0 44.87 1254
SGG116 280.21 280.34 13.2 6.40 84
SGG118 355.88 356.50 62.3 5.54 345
SGG120 195.29 195.73 43.5 19.11 831
Average of 26 holes above
350 cmg/t Au40.9 22.4 918
Average of 32 holes above
300 cmg/t Au37.8 21.4 808
GR
EA
T B
AS
IN
HO
LE
SIn
clu
de
s
His
tori
cal
Ho
les
39
Great Basin Gold Ltd.
Burnstone Project
AREA 2 - All Drill Hole Results (True Widths)
Hole
Number
From
(metres)
To
(metres)
Intercept
(cm)
Gold
(g/t)
Thickness
x Grade
(cmg/t)
1898 461.08 462.15 106.6 2.05 219
1950 1091.92 1092.35 42.6 18.85 803
2200 750.71 751.19 47.9 9.16 438
2410 557.03 557.42 39.0 7.25 283
2497 292.81 293.82 100.7 0.85 85
2520 394.74 394.98 24.1 18.21 440
2663 391.42 391.64 22.3 1.66 37
2670 1062.21 1062.40 19.0 2.59 49
2721 338.28 338.57 28.8 3.85 111
2849 465.81 466.80 98.6 6.07 599
2850 530.87 531.13 26.1 2.52 66
SG13 401.27 401.80 52.5 10.41 546
SG14 399.82 400.19 36.5 12.99 474
SG15 459.04 459.28 24.4 3.56 87
SG3 554.98 555.65 67.3 15.78 1063
SG8 478.00 478.15 14.6 0.22 3
SG9 539.33 540.02 68.9 5.89 406
HIS
TO
RIC
AL
HO
LE
S
40
Great Basin Gold Ltd.
Burnstone Project
AREA 2 - All Drill Hole Results (True Widths)
Hole
Number
From
(metres)
To
(metres)
Intercept
(cm)
Gold
(g/t)
Thickness
x Grade
(cmg/t)
SGG041 775.99 776.25 26.1 0.58 15
SGG043 750.48 750.93 45.1 0.28 13
SGG046 445.25 445.60 35.4 8.71 308
SGG048 554.92 555.27 34.9 3.08 108
SGG049 589.07 589.75 67.5 2.71 183
SGG050 439.16 439.61 44.9 11.91 535
SGG051 395.37 396.18 81.3 4.48 364
SGG052 1288.53 1288.92 39.2 2.45 96
SGG053 414.97 415.57 60.1 2.10 126
SGG054 559.93 560.21 27.7 5.57 154
SGG056 490.29 491.57 127.9 2.90 371
SGG058 367.22 367.81 59.3 4.55 270
SGG059 543.10 543.60 50.3 4.82 243
SGG060 602.42 602.98 55.6 6.50 362
SGG061 414.29 414.89 60.1 1.70 102
SGG063 355.83 356.00 16.8 11.84 199
SGG065 353.96 354.96 100.3 0.17 17
SGG066 1171.23 1171.39 16.1 3.56 57
SGG067 677.07 677.38 30.5 10.15 309
SGG070 418.02 419.09 106.9 4.51 482
SGG072 672.51 672.69 18.4 2.38 44
SGG073 404.69 405.06 37.1 2.64 98
SGG075 511.77 511.92 14.9 1.25 19
SGG078 548.57 548.72 15.0 11.95 179
SGG079 612.29 612.44 14.9 0.68 10
SGG081 1314.32 1314.72 39.7 27.10 1074
SGG090 753.69 754.61 91.5 7.14 653
SGG091 417.02 417.50 47.7 3.84 183
SGG093 488.37 488.58 21.0 12.50 263
SGG094 537.84 538.23 38.7 10.49 406
SGG096 631.72 632.24 51.9 1.75 91
SGG099 462.12 462.28 15.9 2.08 33
SGG100 530.85 531.11 25.8 10.67 276
SGG102 425.09 425.87 78.1 1.53 119
SGG103 438.81 438.96 15.1 17.41 263
SGG107 691.11 691.44 32.5 7.05 229
SGG115 799.90 800.55 64.7 3.90 253
SGG121 659.30 660.53 123.2 1.05 129
Average of 16 holes above
350 cmg/t Au64.1 8.8 563
Average of 18 holes above
300 cmg/t Au61.4 8.7 535
GR
EA
T B
AS
IN H
OL
ES
Inclu
des
His
tori
cal
Ho
les
41
Great Basin Gold Ltd.
Burnstone Project
AREA 3 - All Drill Hole Results (True Widths)
Hole
Number
From
(metres)
To
(metres)
Intercept
(cm)
Gold
(g/t)
Thickness x
Grade
(cmg/t)
2985 381.90 382.18 27.5 35.77 983
3090 1090.86 1091.47 61.0 21.60 1317
SGG064 428.18 428.34 15.6 28.77 450
SGG071 358.06 358.20 14.4 1.93 28
SGG074 380.06 380.59 53.4 11.80 630
SGG077 352.37 352.53 16.0 20.98 335
SGG080 355.25 355.41 15.9 35.06 557
SGG082 342.47 342.62 15.2 2.64 40
SGG084 396.43 397.02 59.1 2.58 153
SGG086 369.14 369.31 16.6 2.01 33
SGG089 241.90 242.06 15.9 0.72 12
SGG092 461.38 461.52 14.3 5.92 85
SGG095 319.70 319.86 16.3 25.40 415
SGG098 362.10 362.19 8.6 0.22 2
SGG104 434.11 434.41 30.4 31.76 965
SGG109 346.49 346.72 22.6 0.33 7
SGG110 408.60 408.75 14.9 27.31 406
SGG114 396.89 397.08 18.8 1.17 22
SGG123 485.81 485.97 15.5 6.74 105
Average of 8 holes above
350 cmg/t Au29.4 24.4 715
Average of 9 holes above
300 cmg/t Au27.9 24.1 673
HISTORICAL
HOLES
GR
EA
T B
AS
IN H
OL
ES
Inclu
des
His
tori
cal
Ho
les
42
ILLUSTRATIONS
Regional Geology Map Cross Section A-A’ – Area 1 Cross Section B-B’ – Area 2 Cross Section C-C” – Area 3
Axial fault
-2944000
-2954000
-2952000
-2950000
-2948000
-2946000
-2958000
-2956000
-46000
-44000
-42000
-40000
-38000
-36000
-34000-2942000
WP1
816
835
852
879
946
969
1111
1684
1688
1695
1714
1730
1749
1765
1774
1780
1807
1808
1809
1843
1877
1890
1912
2
2126
2142
2168
2201
2216
2314
2346
2401
2489
2510
2531
2588
2643
2659
2671
2693
2722
2723
2728
2729
2730
2733
2734 2755
2757
2773
2786
278
2790
2791
2799
2809
2810
2927
BH2 ( c ) BH3
VFN1
VFN2
VFN3
VFN4
VFN5
VTN1
76M-1
76M-5
76M-6
76M-7
76M-11
RE1
RE2
RRE1
RRE2
RRE4
RRE5
RRE9
BK1
B
GG1
DMR1
SG4
SG6
SG7
SG11
SG16 S
S
SGG024SGG027
SGG028SGG031
SGG032
S
SGG045
SGG088
SGG09
* Darker shades represents the outcropgeology and lighter shade the local geology
Intrusive Rocks
Quartz Diorites
Dolerite
Scattered Reef zone - conlomerate/quartzite
SGG043Drill Hole Location and Number
Ventersdorp Sequence
Ventersdorp lava flows
Alberton Porphyry
Drab and Intermediate Quartzite
Platberg Volcaniclastic Rocks
Central Witwatersrand Sequence
Faults
Lower Wits quartzites with conglomerate
Iron formations and siltites.
Bird Amygdaloidal lava flows
Main Bird Quartzite
Lower Wits quartzites
Lower Witwatersrand Sequence
Karoo Sedimentary Rocks
Black reef and Dolomite
Legend
Area 1Area 1Area 1Area 1Area 1Area 1Area 1Area 1Area 1
Area 4Area 4Area 4Area 4Area 4Area 4Area 4Area 4Area 4
1
2
3
