1. INTERNATIONAL MONTORO RESOURCES LTD.
ZTEM 2D Synthetic Modeling
Pecors/Serpent River Project, Elliot Lake ON
Buried Magmatic Massive Sulphide Target
BY JM Legault, M.Sc.A., P.Eng, P.Geo Chief Geophysicist – Geotech Ltd.
6-Jan-2017

2. Modeling Objectives Pecors 3D Magnetic Inversion ~3km
From: Sent: Sunday, November 27, :19 AM To: Jean M. Legault Subject: RE: ZTEM information
Jean
I made up three hypothetical orebodies that I believe might be achievable for the project in question and I calculated an average conductivity for the body based on a mix of 35% pyrrhotite, 20% chalcopyrite, 15 % pyrite and 30% rock. This would work out to a conductivity of 3.6 mSm. You may have better numbers than I and if so feel free to substitute your own. The three hypothetical orebodies are as follows
30 Mt -  600m length 110m wide and 300 m thick
15Mt – 600m length 50m wide and 150 m thick
7.5 Mt – 600m length 25m wide and 50m thick
If we were to bury each one at depths of 700m, 1400m and 2100m which one if any or what combination would produce a response(s) on the ZTEM.
Any help you could provide would be much appreciated
Sincerely
Don Hawke
~3km
(after Reed, 2014)
Pecors ZTEM 2D Synthetic Model
Pecors Magnetic Anomaly
6000 m
Objective: Using Geologic Model from Magnetic inversion Create Conceptual Model and Determine detectability of buried ~7.5Mt Magmatic massive sulphide body buried at 700m, 1400m & 2100m using ZTEM airborne EM.
Method: Use 2D MT forward modeling code of Wannamaker et al. (1985) in GeotoolsTM to obtain ZTEM synthetic fwd model Tipper data and then invert using Geotech Av2dtopoTM 2D ZTEM inversion code. Test for 200m, 300 and 500m minimum depth.
Volume = Mass = 7,500,5000 tonnes x 1000 kg/t x 1000 g/kg = 2,142,857 m3
Density g/cc x (100 cm/m)3
Approx. Size = 2,142,857 m = Approx. 300m wide x 10m thick x 700m long
(after Reed, 2014)

3. MODEL 1 X Z X Z Pecors Model 1 – ZTEM 2D Inversion Model
1) Model 1 (100 S Body at 700m) – 2D Forward Model)
Pecors Model 1 – ZTEM 2D Inversion Model
Air Layer below helicopter 10k ohm-m x 50m thick
Tzx In Phase - Synthetic/Observed
+/ approx. ZTEM noise floor
Huronian Cover Rocks
500 Ω-m x 300m thick
700m
MS Body
0.1 ohm-m
10m Thick (100 Siemens)
300m Wide
Tzx In Phase - Calculated
Archean Basement
1000 Ω-m
300m
Mafic Intrusive Ω-m
6000 m
Tzx Quadrature - Synthetic/Observed
+/ approx. ZTEM noise floor
Tzx Quadrature - Calculated
+25%
In Phase Tzx Tipper from 2D ZTEM Fwd Model
Reverse Cross-Overs ( Hz) = Resistor
22Hz
ZTEM 2D Resistivity 0%
720Hz
+/ approx. ZTEM noise floor
~700 m
Tzx (In-line) In-Phase (%)
Conductor
~3 Ωm
~ m Wide
At ~750m Depth
Normal Cross-Overs (22-90Hz) = Conductor
Resistive Host ~1000 Ωm
Comments: In-Phase responses are well above Expected Threshold Noise levels. X Z X Z
-25%
6000 m
Comments: The expected ZTEM response is moderate-strong In-phase response and Quadrature response. The 2D inversion returned a Resistivity model that appears to resolve the Targeted MS bodies at 700m depth and is easily detectible above S/N levels. However the 2D does not recover the Layered Cover or the Mafic Intrusive.
+25%
Quadrature Tzx Tipper from 2D ZTEM Fwd Model
Normal Cross-Over (720z) = Resistor
Tzx (In-line) Quadrature (%) 0%
720Hz
+/ approx. ZTEM noise floor
(Comments: XQD Profile reversals due to Different Quadrature Polarity Convention
Used in ZTEM Av2dinv code (exp(-iwt) versus Geotools (exp(+iwt)).
Reverse Cross-Overs (22H-360z) = Conductor
22Hz
Comments: All Quadrature responses are well above Expected Threshold Noise levels.
-25%
2D Fwd Modeling using Wannamaker et al. (1985) PW2dfwd code in Geotools

4. MODEL 2 X Z X Z Pecors Model 2 – ZTEM 2D Inversion Model
1) Model 2 (100 S Body at 1400m) – 2D Forward Model)
Pecors Model 2 – ZTEM 2D Inversion Model
Air Layer below helicopter 10k ohm-m x 50m thick
Tzx In Phase - Synthetic/Observed
+/ approx. ZTEM noise floor
Huronian Cover Rocks
500 Ω-m x 300m thick
Mafic Intrusive Ω-m
1400m
Tzx In Phase - Calculated
Archean Basement
1000 Ω-m
300m
MS Body
0.1 ohm-m
10m Thick (100 Siemens)
300m Wide
6000 m
Tzx Quadrature - Synthetic/Observed
+/ approx. ZTEM noise floor
Tzx Quadrature - Calculated
+25%
In Phase Tzx Tipper from 2D ZTEM Fwd Model
Reverse Cross-Overs (45-720Hz) = Resistor
22Hz
ZTEM 2D Resistivity 0%
+/ approx. ZTEM noise floor
720Hz
~1300 m
Tzx (In-line) In-Phase (%)
Normal Cross-Over (22Hz) = Conductor
Resistive Host ~1000 Ωm
Conductor
~18 Ωm
~ m Wide
At ~1300m Depth
Comments: In-Phase responses are above Expected Threshold Noise levels. X Z X Z
-25%
6000 m
Comments: The expected ZTEM response is moderate In-phase response and Quadrature response. The 2D inversion returned a Resistivity model that appears to resolve the Targeted MS bodies at ~1300m depth and is easily detectible above S/N levels. However the 2D does not recover the Layered Cover but maybe Resistive Intrusive.
+25%
Quadrature Tzx Tipper from 2D ZTEM Fwd Model
Normal Cross-Overs ( z) = Resistor
Tzx (In-line) Quadrature (%)
720Hz
+/ approx. ZTEM noise floor 0%
(Comments: XQD Profile reversals due to Different Quadrature Polarity Convention
Used in ZTEM Av2dinv code (exp(-iwt) versus Geotools (exp(+iwt)).
22Hz
Reverse Cross-Overs (22-90z) = Conductor
Comments: All Quadrature responses are above Expected Threshold Noise levels.
-25%
2D Fwd Modeling using Wannamaker et al. (1985) PW2dfwd code in Geotools

5. MODEL 3 X Z X Z Pecors Model 3 – ZTEM 2D Inversion Model
1) Model 3 (100 S Body at 2100m) – 2D Forward Model)
Pecors Model 3 – ZTEM 2D Inversion Model
Air Layer below helicopter 10k ohm-m x 50m thick
Tzx In Phase - Synthetic/Observed
+/ approx. ZTEM noise floor
Huronian Cover Rocks
500 Ω-m x 300m thick
6000 m
Mafic Intrusive Ω-m
Tzx In Phase - Calculated
2100m
Archean Basement
1000 Ω-m
MS Body
0.1 ohm-m
10m Thick (100 Siemens)
300m Wide
300m
Tzx Quadrature - Synthetic/Observed
+/ approx. ZTEM noise floor
Tzx Quadrature - Calculated
+25%
In Phase Tzx Tipper from 2D ZTEM Fwd Model
Reverse Cross-Overs (45-720Hz) = Resistor
22Hz
ZTEM 2D Resistivity 0%
+/ approx. ZTEM noise floor
~1800 m
720Hz
Tzx (In-line) In-Phase (%)
Normal Cross-Over (22Hz) = Conductor
Resistive Host ~1000 Ωm
Comments: In-Phase responses are above Expected Threshold Noise levels. X Z X Z
Conductor
~26Ωm
~ m Wide
At ~1800m Depth
-25%
6000 m
Comments: The expected ZTEM response is moderate In-phase response and Quadrature response. The 2D inversion returned a Resistivity model that appears to resolve the Targeted MS bodies at ~1800m depth and is easily detectible above S/N levels. However the 2D does not recover the Layered Cover but maybe resistive Intrusive.
+25%
Quadrature Tzx Tipper from 2D ZTEM Fwd Model
Normal Cross-Overs ( z) = Resistor
Tzx (In-line) Quadrature (%)
720Hz
+/ approx. ZTEM noise floor 0%
(Comments: XQD Profile reversals due to Different Quadrature Polarity Convention
Used in ZTEM Av2dinv code (exp(-iwt) versus Geotools (exp(+iwt)).
22Hz
Reverse Cross-Overs (22-90z) = Conductor
Comments: All Quadrature responses are above Expected Threshold Noise levels.
-25%
2D Fwd Modeling using Wannamaker et al. (1985) PW2dfwd code in Geotools

6. CONCLUSIONS & RECOMMENDATIONS
Synthetic 2D modeling was performed to test the applicability / suitability of ZTEM for exploring for buried magmatic massive sulphides in the Pecors/Serpent River project near Elliot Lake, Ontario.
7.5 Mt body was estimated for 3.5gm/cc density to be 10m thick x 300m wide x 700m long. But 2D model ignores strike length so infinite strike was assumed for 10m x 300m wide conductor. Conductivity fixed at 0.1 ohm-m for Nickel Sulphides for modeling.
Three different model scenarios were studied: 100 Siemens (0.1 Ω-m x 10m thick (5 siemens) conductors at +700m, +1400m and +2100m depths of burial, associated with massive-sulphide bodies below thick Huronian cover and inside Archean mafic intrusive.
The synthetic 2D ZTEM response was calculated using the Wannamaker et al. (1985) 2D MT forward modeling code in Geotools.
These synthetic data were then used as input for the 2D ZTEM inversion using the Geotech Av2Dtopo code by Wannamaker (Uof Utah).
The 2D synthetic results suggest that all these m deep targets will be easily detected as anomalies; however it will not be possible to recover the layered cover or to differentiate/discriminate individual mafic intrusive bodies in Archean basement.
Note, 15Mt and 30Mt sulphide bodies were not tested in ZTEM modeling, but given the success for 7.5 Mt, larger, more highly conductive bodies should also be detectible, provided they area reasonably 2-dimensional (i.e., approx. >1-3km long).
We expect that the ZTEM tipper amplitudes will weaken for shorter strike length 3D bodies.
Respectfully submitted
JM Legault, M.Sc.A., P.Eng, P.Geo Chief Geophysicist – Geotech Ltd.
6-Jan-2017