Minotaur 5 dec14_sa expl mining conf
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Transcript of Minotaur 5 dec14_sa expl mining conf
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The Artemis Cu-Au Deposit – and what it means for IOCG exploration in SA
A. P. Belperio
SA Exploration and Mining Conference
Adelaide, 5 December 2014
Minotaur Exploration Limited | ASX: MEP
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Artemis polymetallic Cu-Au-Zn-Ag discovery
was announced 31 July 2014. • How was the discovery made?
• What is it?
• What are the plans going forward?
• What does it mean for IOCG exploration (in SA) ?
Artemis Cu-Au Discovery
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Minotaur IOCG Focus Areas since 2001
• Gawler Craton
• Cloncurry
Mineralisation Styles
• Haematite-hosted IOCG
• Magnetite-hosted IOCG
• Pyrrhotite-hosted ISCG
Targeting undercover, particularly the highly
reduced and conductive cover marginal to
Cloncurry, necessitates a focused and selective
geophysical approach.
Artemis Cu-Au Discovery
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IOCG deposit styles – an extremely broad church
Almost every deposit is different
Artemis Cu-Au Discovery
IOCG Deposit Examples Mineralisation Form of Iron Targeting
Styles Methodology
Barren Ironstone SE Missouri, Kiruna n/a Mag, Hm Magnetics, Gravity
Tenant Ck Ironstone Peko, Geko Au-Cu-Bi Mag, Po, Hm Magnetics, Gravity
Osborne ironstone Osborne Cu-Au Mag, Hm, Py, Po Magnetics, Gravity
Haematite Breccia Olympic Dam, Prominent Hill Cu-Au-U-REE Hm Gravity, IP
Magnetite Breccia Ernest Henry, Candelaria, Salobo Cu-Au Mag, Bio Magnetics
Magnetite-Apatite Kiruna, Acropolis n/a Mag Magnetics
Iron Sulphide Cormorant, Eloise, Artemis, Kulthor Cu-Au-Zn-Pb-Ag-Co Po, Py Electrical Conductivity
Cobaltiferous Nico Au-Bi-Co-Cu Mag, Hm, Bio Magnetics, Radiometrics
Common Features: Bimodal igneous activity, mantle tapping structures, extensive regional Na and K alteration and widespread Fe metasomatism
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IOCG style of deposits – an extremely broad church
Almost every deposit is different
Artemis Cu-Au Discovery
Mt Woods Inlier
TMI
Joes Dam South Prospect
Prominent Hill
Chalcocite – haematite - gold breccia
+200m @ 1.5% Cu, 0.5 g/t Au, Ur, REE
Mt Woods : Manxman and Joes Dam Prospects
Magnetite hosted Cu-Au : 287m @ 0.23% Cu
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Cloncurry - Naraku
Naraku
• Black soil plains north of Ernest Henry
• No geochemical signals
• Limited electrical geophysical penetration
• Initially gravity and magnetics
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Cormorant ISCG
JOGMEC JV since 2010
• Successfully penetrated ultra-conductive cover
beneath black soil plains
• Major Iron Sulphide Copper Gold system (ISCG)
encountered within reduced host rock terranes
• 15+km, 20+m thick, massive & breccia pyrrhotite,
persistently mineralised Cu-Au-Co
• Epigenetic Fe system as large as Prominent Hill
• Weakly magnetic, highly conductive
MIN04 : 20m @ 0.2% Cu, 0.02% Co from 160m
MIN07 : 56m @ 0.1% Cu, 0.03 g/t Au from 186m
MIN10 : 72m @ 0.21% Cu, 0.02% Co from 414m
Cormorant
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IOCG – ISCG Geophysical characteristics
IOCG deposits (magnetite-rich; large; disseminated)
(Ernest Henry, Osborne, Mt Elliott-Swan):
Significant positive magnetic anomalies
Positive gravity anomalies
Strong IP chargeability anomalies
Oxidised host rock terrane
Weak to no EM anomalies
Broad alteration haloes
ISCG deposits (pyrrhotite-rich; small; high grade)
(Cormorant, Eloise, Kulthor, East Osborne, Artemis):
No positive magnetic anomalies
No or limited gravity anomalism
Positive IP chargeability anomalies
Reduced host rock terrane
Strong ground EM anomalies
Limited alteration haloes
Osborne
Ernest Henry
Kulthor
Eloise
Artemis
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Eloise ISCG
Shift towards Eloise driven by:
• Recognition of the ISCG style as a
significant and different (small, high
grade) style of Cu-Au mineralisation
• Understanding of different exploration
tools required, particularly EM and AEM
• Requirement for shallower ground that
would allow airborne techniques to be
used as a more rapid screening tool
• Acquired BRW Eloise tenements
December 2013 with pre-determined
exploration strategy and funding partner
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Eloise JV
November 2013
• $1.7M Year 1 Work Program
commenced
Primary AEM survey
(Nov-Dec13)
Ground EM follow-up at
16 targets (Feb-Apr14)
Drill test 10 best targets
(May-July 2014)
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EVT54
Late-time, Z-component VTEM image
VTEM target EVT 54
Late-time VTEM image and line profile
• VTEM target EVT54 of particular
interest – 350m west of the Sandy
Creek inferred resource
• Outcropping BIF and some ironstone
“gossan” had attracted some past
attention, some historic EM, and “sniffs”
of copper and gold mineralisation
encountered
• EVT54 therefore became a priority
target for ground EM follow-up
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EVT54
Late-time, Z-component VTEM image
VTEM Target EVT 54 - Ground EM
• Ground EM at EVT54 confirmed a
steeply dipping, high conductance
body, from c. 80m below ground level
• Original plate model from the fixed
loop ground EM neatly fitted between
historic drillholes in the vicinity
• EVT54 recommended as the premier
target based on conductance and
associated gold and copper hits
nearby.
• Drillhole EL14D09 successfully tested
the target, named Artemis
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Artemis
• Discovery hole 22m @ 3.02% Cu, 3.81 g/t
Au, 6.64% Zn, 1.35% Pb, 112 g/t Ag from 157 to
179 m
• Two further holes 50m up-dip and
down-dip
• Drillhole EL14D10 : 21m @ 0.84% Cu, 0.73
g/t Au, 5.06% Zn,, 1.85% Pb, 69 g/t Ag
• Drillhole EL14D12 : 24m @ 1.58% Cu, 2.12
g/t Au, 4.74% Zn, 1.13% Pb, 54 g/t Ag
• 122m vertical section drilled at this
point plus down-hole EM can “see” a
further 50m incrementally
• Drilling suspended to allow new
heritage clearance surveys, new
geophysics, planning of systematic drill
programs and Joint Venture approvals.
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Artemis
Drillhole EL14D09, 166.6m: coarse, massive sulphides including chalcopyrite (yellow), sphalerite
(black), pyrrhotite (bronze-grey) and calcite (white to pale grey) – no host rock brecciation.
Metre interval assay: 36% Fe, 2.7% Cu, 1.5 ppm Au, 6.7% Zn, 1.1% Pb, 111 ppm Ag
What is Artemis:
• Blind deposit of late fracture fill massive sulphide
• Fe-Cu-Zn-Pb sulphides. Very limited alteration halo or host rock brecciation
• Steep, tabular body, structurally controlled. No significant magnetic or gravity expression
• Responsive to Down-hole and Across-hole EM
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Artemis - mineralogy
Cu Au Zn
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Artemis – Eloise Comparison
• Mineralogical associations (Eloise after Baker, 1998)
Element Artemis Eloise Major mineral
EL14D09
Fe 20-38% No data Pyrrhotite
Cu 0.2-8% 0.1-25% Chalcopyrite
Zn 0.02-14% 0.1-1.0% Sphalerite
Au 0.1-20 ppm 0.1-15 ppm Electrum
Ag 0.1-289 ppm 0.1-60 ppm Electrum
Pb 0.1-36,000 ppm 0.1-300 ppm Galena
As 0.1-9000 ppm 0.1-500 ppm Arsenopyrite
Bi 0.1-500ppm 0.1-100 ppm Bismuthinite
Co 0.1-2200 ppm 5-750 ppm Cobaltite
Bright whitish-yellow gold grains (or
possible electrum) (2µm to 20µm)
circled, mostly in pyrrhotite, some in and
on margins of chalcopyrite.
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Artemis – Eloise Comparison
• Mineralogical association, physical and structural styles at
Artemis appear remarkably similar to the Eloise deposit
• Eloise comprise a number of offset pyrrhotite-dominated
massive sulphide lenses of short strike length (<200m) but
great down dip extent.
• Blind at surface, late brittle offsets
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Artemis – Proposed Work
Accelerated $6M workplan from
Oct 2014 to Jun 2015
• Systematic drill testing at Artemis
• Along strike and down dip extent
to be guided by systematic downhole surveys
• Thickness – grade variation mapping
• 40+ holes, 18,000m, 2 DDH Rigs
• Metallurgy, petrology and resource definition
• Along-structure extensions to north and south
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Artemis – Long Section View and Eloise Comparison
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Artemis – Proposed Work
Accelerated $6M workplan from
Oct 2014 to Jun 2015
• Systematic drill testing at Artemis
• Along strike and down dip extent
to be guided by systematic downhole surveys
• Thickness – grade variation mapping
• 40+ holes, 18,000m, 2 DDH Rigs
• Metallurgy, petrology and resource definition
• Along-structure extensions to north and south
• Connections with Sandy Creek and greater Artemis area
• Greenfield targeting: Drill testing a further 10 regional target
• Greenfield targeting: Deep EM along the Levuka Shear
Artemis
Sandy Creek
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Artemis – Proposed Work
Accelerated $6M workplan from
Oct 2014 to Jun 2015
• Systematic drill testing at Artemis
• Along strike and down dip extent
to be guided by systematic downhole surveys
• Thickness – grade variation mapping
• 40+ holes, 18,000m, 2 DDH Rigs
• Metallurgy, petrology and resource definition
• Along-structure extensions to north and south
• Connections with Sandy Creek and greater Artemis area
• Greenfield targeting: Drill testing a further 10 regional targets
• Greenfield targeting: Deep EM along the Levuka Shear
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SA IOCG
So what are the lessons for SA
• Successful exploration requires the right
mix of models, tools and financial
commitment
• What are the most appropriate tools given
the particularly hostile Australian cover
problem
• Don’t fixate on one model. Make sure the
exploration program is funded appropriately
for the task
• Size isn’t everything, grade is king
• Where are the key structures controlling
fluid flow in IOCG systems
• What are the host rock packages and how
will that determine preferred Fe species
• What are the appropriate tools to for these
targets in these environments
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This presentation has been prepared by the management of Minotaur Exploration Limited (“Minotaur”, ASX: MEP) for the general benefit of analysts, brokers and
investors and does not constitute specific advice to any particular party or persons. Information herein is based on publicly available information, internally developed
data and other sources. Where an opinion, projection or forward looking statement is expressed in this presentation, it is based on the assumptions and limitations
mentioned herein and is an expression of present opinion only. No warranties or representations are made or implied as to origin, validity, accuracy, completeness,
currency or reliability of the information. Minotaur specifically disclaims and excludes all liability (to the extent permitted by law) for losses, claims, damages, demands,
costs and expenses of whatever nature arising in any way out of or in connection with the information, its accuracy, completeness or by reason of reliance by any
person on any of it. Where Minotaur expresses or implies an expectation or belief as to the success of future exploration and the economic viability of future project
evaluations, such expectation or belief is expressed in good faith and is believed to have a reasonable basis. However, such projected outcomes are subject to risks,
uncertainties and other factors which could cause actual results to differ materially from projected future results. Such risks include, but are not limited to, exploration
success, metal price volatility, changes to current mineral resource estimates or targets, changes to assumptions for capital and operating costs as well as political and
operational risks and government regulatory outcomes. MEP disclaims any obligation to advise any person if it becomes aware of any inaccuracy in or omission from
any forecast or to update such forecast.
Information in this presentation that relates to exploration results for Minotaur Exploration Ltd is based on information compiled by Dr. A. P. Belperio, who is a Director
and full-time employee of the Company and a Fellow of the Australian Institute of Mining and Metallurgy. Dr. Belperio has sufficient experience relevant to the style of
mineralisation and type of deposits under consideration and to the activity that he has undertaken to qualify as a Competent Person as defined in the 2012 Edition of
the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves” (JORC Code). Dr. Belperio consents to inclusion of this information
in the form and context in which it appears.
Competent Person’s Statement
Disclaimer
Disclaimer
Daughter of Zeus and Leto and the twin sister of Apollo. She was the Hellenic goddess of the hunt.
Artemis