Exploration and DiscoveryExploration and Discoverywith the Geotech VTEMwith the Geotech VTEM

Versatile time domain EMVersatile time domain EM

Airborne System SpecificationsAirborne System Specifications

30 Hz Primary Frequency30 Hz Primary FrequencyBi-polar 16.6 millisecond half cycleBi-polar 16.6 millisecond half cyclePulse duration 4.6 to 7.5 millisecondsPulse duration 4.6 to 7.5 millisecondsDipole moment 425,000 to 600,000 + nIADipole moment 425,000 to 600,000 + nIAHorizontal central loop or in-loop systemHorizontal central loop or in-loop system Transmitter - 26.1 m diameter 4 turn loopTransmitter - 26.1 m diameter 4 turn loopReceiver – 1.1 m diameter 100 turn coilReceiver – 1.1 m diameter 100 turn coil0.1 second sampling, minimum 25 channels0.1 second sampling, minimum 25 channelsdB/dt finite impulse responsedB/dt finite impulse responseB-field and Deconvolved options B-field and Deconvolved options

Transient Decay-Transient Decay- Bounded Object Bounded Object

Langmuir L3520

-5

-4

-3

-2

-1

0

1

2

3

0 1000 2000 3000 4000 5000 6000 7000

Time (microseconds)

Ln

(pV

/(A

mp

x m

^4)

A~e¯(t/τ)

Ln(A) = -(t/τ)

Tau = Slope = Δt / Ln ΔA

ExamplesExamples

Document the early stages of a New Ni-Cu-PGE Document the early stages of a New Ni-Cu-PGE Discovery in Langmuir Twp (35 Km south-east of Discovery in Langmuir Twp (35 Km south-east of Timmins).Timmins).Show how Late Time analysis, CDI Show how Late Time analysis, CDI computations and BHEM can help orientate the computations and BHEM can help orientate the drilling program. drilling program.

Using an example of Poorly Conducting Using an example of Poorly Conducting Sphalerite mineralization, show how Early Time Sphalerite mineralization, show how Early Time analysis can assist in priorizing the exploration analysis can assist in priorizing the exploration program.program.

Langmuir Area GeologyLangmuir Area Geology

Section of survey – 2VD image + conductor symbols (75 m line spacing).

Conductivity-depth Image – L3520Conductivity-depth Image – L3520

Conductivity-depth Image – L3515Conductivity-depth Image – L3515

Bore Hole 3-comp TEMBore Hole 3-comp TEM

Z - Component X - Component

Prism Model ResultsPrism Model Results

Line Conductance VTEM Tau BH Tau Depth Dip/Direction

3510 2.8 S/m x 25 m 60 m 82.5 (N)

3515 2.5 S/m x 60 m 90 m 70(N)

3520 3.0 S/m x 60 m 4.24 ms 4.6 ms 75 m 85(S)

3525 3.0 S/m x 65 m 90 m 72.5(S)

3530 3.5 S/m x 40 m 95 m 90

Low Conductance TargetsLow Conductance Targets

(known sphalerite occurrences)(known sphalerite occurrences)

Early Time Channels (70,90,110 & Early Time Channels (70,90,110 & 130 130 µµsecsec))

Mid Time Channel (1130 Mid Time Channel (1130 µsec)µsec)

Computed Conductance & Tau Computed Conductance & Tau Values for weak TargetsValues for weak Targets

Area Conductance SRange Mean

Tau millisecondRange Mean

A 0.5-1.0 0.8 ---- <0.01

B 0.2-0.5 0.4 ---- <0.01

C 1.5-4.0 2.8 0.01-1.6 1.1

D 4.2-5.9 4.3 4.5-4.9 4.7

E 0.4-0.9 0.5 0.01-0.6 0.2

F 0.3-1.8 1.1 0.01-1.5 0.1

Summary - LangmuirSummary - Langmuir

Both geology and Ni-Cu-PGE Both geology and Ni-Cu-PGE mineralization similar to Kambalda –w Ausmineralization similar to Kambalda –w Aus

VTEM provided “low noise” late time data VTEM provided “low noise” late time data required for accurate determination of required for accurate determination of conductance and Tau values and conductance and Tau values and modelingmodeling

Summary – Langmuir cont’dSummary – Langmuir cont’d

VTEM data provided CDI’s showing VTEM data provided CDI’s showing confirming evidence for a wide zone of confirming evidence for a wide zone of mineralization and low amplitude folding to mineralization and low amplitude folding to the south of the discovery zonethe south of the discovery zone

3 component bore hole data provided an 3 component bore hole data provided an accurate logging of the limits of the overall accurate logging of the limits of the overall zone(s) and of the higher grade sections zone(s) and of the higher grade sections withinwithin

Summary – Low Conductance Summary – Low Conductance TargetsTargets

VTEM maps very early time expression of VTEM maps very early time expression of low conductance sphalerite mineralized low conductance sphalerite mineralized zones providing accurate contrasting of zones providing accurate contrasting of weak conductances and Tau valuesweak conductances and Tau values

Selection of targets can be assisted by Selection of targets can be assisted by early time imaging, conductance and Tau early time imaging, conductance and Tau valuesvalues