Deep exploration: reasons and results15 August 2013

Chris WijnsGroup Geophysicist, First Quantum Minerals

What is “undercover”?

• Is not lack of outcrop– Deeply weathered in-situ regolith is usually amenable to soil

geochemistry for geological and alteration mapping

• Is not leached regolith (leached of target metal)– still usually holds other geochemical indicators (Chile=Mo,

Kamoa=Zn,Pb)

• Is transported overburden that masks or displaces surface geochemical expression of mineralisation– e.g., windblown sand, transported gravel, young surface

volcanic flows

• Is not lack of outcrop– Deeply weathered in-situ regolith is usually amenable to soil

geochemistry for geological and alteration mapping

• Is not leached regolith (leached of target metal)– still usually holds other geochemical indicators (Chile=Mo,

Kamoa=Zn,Pb)

• Is transported overburden that masks or displaces surface geochemical expression of mineralisation– e.g., windblown sand, transported gravel, young surface

volcanic flows

Reasons for looking deep

• Junior purpose: get an intersection, doesn’t matter if it will ever be economic

• Top end of town: have $$, will probably mine it (more concerned with tonnes than profit)

• “Research hole”: geological understanding will let us explore better near the surface

• Junior purpose: get an intersection, doesn’t matter if it will ever be economic

• Top end of town: have $$, will probably mine it (more concerned with tonnes than profit)

• “Research hole”: geological understanding will let us explore better near the surface

Do we really need to look deep?

• As an industry … maybe• As individual companies … no• Do we need to look under cover? … Yes

• As an industry … maybe• As individual companies … no• Do we need to look under cover? … Yes

First Quantum deep exploration examples

• NiS deep drilling on seismic + concept• Sed Cu deep drilling on concept alone• NiS deep drilling on seismic + concept• Sed Cu deep drilling on concept alone

Kevitsa Ni-Cu

• Mafic/UM intrusion into interlayered metavolcanic/metased country rock

• Grades 0.3% Ni, 0.4% Cu, 275 M tonnes

• Mafic/UM intrusion into interlayered metavolcanic/metased country rock

• Grades 0.3% Ni, 0.4% Cu, 275 M tonnes

Kevitsa Ni-Cu

• Mafic/UM intrusion into interlayered metavolcanic/metased country rock

• Grades 0.3% Ni, 0.4% Cu, 275 M tonnes

• Mafic/UM intrusion into interlayered metavolcanic/metased country rock

• Grades 0.3% Ni, 0.4% Cu, 275 M tonnes

Where’s the good stuff?

• Base of intrusion interpretation to constrain exploration for contact style ore

• Base of intrusion interpretation to constrain exploration for contact style ore

Base of intrusion

Defining base of intrusion

Base of intrusion

Base of intrusion

• Drill pierce points + 2D and 3D seismic• Drill pierce points + 2D and 3D seismic

Extension of intrusion?

Extension of intrusion?

• Deep drill hole 1.7 km• Deep drill hole 1.7 km

Gravity and magnetics

Magnetics (RTP)

Gravity (Bouguer)

Sediment-hosted Cu

• African Copperbelt = Lufilian Arc• African Copperbelt = Lufilian Arc

Copperbelt deposit settings

• Schematic stratigraphy, fluid/metal sources, and traps• Schematic stratigraphy, fluid/metal sources, and traps

Hitzman et al, 2010

Copperbelt deposit settings

• Simple structural/chemical trap model• Simple structural/chemical trap model

Copperbelt deposit settings - ores

• predominantly in clastic (less commonly carbonate) sediments; (1) large tonnage deposits in dark shales and carbonates above thick red bed sequence

• predominantly in clastic (less commonly carbonate) sediments; (1) large tonnage deposits in dark shales and carbonates above thick red bed sequence

Copperbelt deposit settings - ores

• predominantly in clastic (less commonly carbonate) sediments; (2) small/large deposits in sandstone or arkose lenses within interbedded sandstone/shale redbed

• predominantly in clastic (less commonly carbonate) sediments; (2) small/large deposits in sandstone or arkose lenses within interbedded sandstone/shale redbed

Kansanshi Cu(-Au)

• Kansanshi domes – mineralisation at each local apex• Kansanshi domes – mineralisation at each local apex

Kansanshi Cu(-Au)

• Kansanshi domes – mineralisation at each local apex• Kansanshi domes – mineralisation at each local apex

Reductant horizon control

• “Middle mixed clastics” ore host• “Middle mixed clastics” ore host

Drilling result

• Nil• Nil

Mapping basement domes with AMT

• AMT conductivity, 16 – 8192 Hz, 1+ km depth resolution

• Control line mappingbasement in the west,dominated by Mwashiashale to east

• AMT conductivity, 16 – 8192 Hz, 1+ km depth resolution

• Control line mappingbasement in the west,dominated by Mwashiashale to east

50 0 50 100 150 200 250

metres

Scale 1:5000

First Quantum Minerals ltdAMT Resistivity SectionLine 3 West of Frontier

Boreholes Overlaid

GRS

121252284301316325336344354369391419455506572677822994

117313471501163817831942

Resistivityohm.m

100 m

FTRC021

100 m

200

FTRC042

100 m

200

FTRC044

100 m

FTRC045

500

750

1000

1250

500750

10001250

658000 658250 658500

658000 658250 658500

Mapping basement domes with AMT

• AMT conductivity, 16 – 8192 Hz, 1+ km depth resolution• AMT conductivity, 16 – 8192 Hz, 1+ km depth resolution

100 0 100 200 300 400 500 600 700

metres

Scale 1:10000-145 -2 4 11 18 30 45 62 78100 155 249 443 822 1827 5441

Resistivityohm.m

100 m

200

FD004

100 m

200

300

FD005

100 m

200

300

400

FD019 FD020

100 m

200

FD085

100 m

200

FD086FD087FD089

100 m

FTCC032

100 m

200

FTRC041

100 m

FTRC075

100 m

FTRC076

100 m

FTRC077

100 m

FTRC078

100 m

FTRC083

100 m

FTRC084FTRC090

100 m

FTRC093FTRC094FTRC096

100 m

FTRC108

100 m

FTRC109

100 m

FTRC110

100 m

FTRC111

FTRC112

100 m

FTRC113

100 m

FTRC114

100 m

LRC063

100 m

LRC066

100 m

200

LRC125

250

500

750

1000

1250

250500

7501000

1250

658750 659000 659250 659500 659750 660000 660250 660500 660750 661000 661250 661500 661750 662000 662250

658750 659000 659250 659500 659750 660000 660250 660500 660750 661000 661250 661500 661750 662000 662250

Mwashia shale

Mwashia shale

Basement?Basement?

Mapping basement domes with AMT

• Long regional lines < 40 km for detection of hidden basement domes

• Long regional lines < 40 km for detection of hidden basement domes

10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 20000 21000 22000 23000 24000 25000 26000 27000 28000 29000 30000 31000 32000 33000 34000 35000 36000 37000 38000 39000 40000 41000

10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 20000 21000 22000 23000 24000 25000 26000 27000 28000 29000 30000 31000 32000 33000 34000

Depth extent 1.4 km

Conclusions

• For First Quantum, deep drilling is about geology and not metal– improving stratigraphic and structural understanding to help

shallow targeting

• Seeing deep is a fight against physics– seismic = $$ vs objectives– geologically constrained inversions of various data sets

• Explorability depends on deposit style– Drill deep for hydrothermal systems with huge alteration

footprints– NiS cannot afford exploration by deep drilling

• For First Quantum, deep drilling is about geology and not metal– improving stratigraphic and structural understanding to help

shallow targeting

• Seeing deep is a fight against physics– seismic = $$ vs objectives– geologically constrained inversions of various data sets

• Explorability depends on deposit style– Drill deep for hydrothermal systems with huge alteration

footprints– NiS cannot afford exploration by deep drilling

End

• What is “under cover”?• Do we need to look deep?• What is “under cover”?• Do we need to look deep?

Pyhasalmi

• 2012 production: 12,600 t Cu, 25,600 t Zn, 891,700 Py• home of the worlds deepest sauna at 1440 metres• 2012 production: 12,600 t Cu, 25,600 t Zn, 891,700 Py• home of the worlds deepest sauna at 1440 metres