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Geophysical Survey Interpretation Report

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(1)The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again.. INSIGHT GEOPHYSICS INC. 95 WALBY DR., OAKVILLE, ONTARIO, CANADA, L6L-4C8 905 465 2996. Geophysical Survey Interpretation Report Gradient and Insight Section Array Induced Polarization /Resistivity Surveys Pistol Lake Project Shebandowan, Ontario, Canada Golden Share Mining Corp. December 2011 C--120. Craig Pawluk Insight Geophysics Inc..

(2) INSIGHT GEOPHYSICS INC.. TABLE OF CONTENTS INTRODUCTION .......................................................................................................... 3 SURVEY GRID............................................................................................................... 4 SURVEY PARAMETERS ............................................................................................ 5 SURVEY EXECUTION .............................................................................................. 10 DATA PRESENTATION............................................................................................ 11 INTERPRETATION...................................................................................................16 CONCLUSIONS AND RECOMMENDATIONS.................................................29. 2.

(3) INSIGHT GEOPHYSICS INC.. INTRODUCTION From November 7 through November 20, 2011, Insight Geophysics Inc. was contracted by Golden Share Mining Corp. to perform an Insight Section IP/Resistivity survey on the Pistol Lake Project located near Shebandowan, Ontario, Canada. The Band Ore property is located approximately 70 km west of the city of Thunder Bay, Ontario, Canada.. General Information Project Name:. Pistol Lake. Survey Type:. Insight Section and Gradient Time Domain Induced Polarization / Resistivity. Client:. Golden Share Mining Corp. Representatives:. Ms. Laurence Huss. PISTOL LAKE GRID LINE MAP. 3.

(4) INSIGHT GEOPHYSICS INC.. SURVEY GRID Grid Location . Province:. Ontario. . General Location:. Shebandowan. . Line Spacing:. 100m. . Station Interval:. 25m. All Line cutting and GPS surveying of the grid was complete by Golden Share.. Survey Specifications IP Survey Survey Type: 4 Second Time Domain Induced Polarization / Resistivity Array Types: Gradient and Insight Section Array AB (Tx dipole spacing):. Multiple AB injections (200m to 1500m). MN (Rx dipole spacing):. 25 meters. Sampling Interval:. 25 meters. 4.

(5) INSIGHT GEOPHYSICS INC.. SURVEY PARAMETERS Apparent Resistivity Let the distances between the four electrodes be given by r1, r2, r3, and r4 as shown in the figure.. Knowing the locations of the four electrodes, and by measuring the amount of current input into the ground, i, and the voltage difference between the two potential electrodes, ÆV, we can compute the resistivity of the medium, rho-a, using the following equation. The resistivity computed using the equation given above is referred to as the apparent resistivity. We call it the apparent resistivity for the following reason. We can always compute rho-a, we only need to know the locations of the electrodes and measure the current and voltage. If, however, the Earth does not have a constant resistivity (that is if the resistivity varies with depth or horizontally), the resistivity computed by the above equation will not represent the true resistivity of the Earth. Thus, we refer to it as an apparent resistivity.. Chargeability (M) True chargeability is the ratio of the over- or secondary voltage, Vs, to the observed voltage, Vo, applied by way of an electrode array so that M = Vs/Vo, expressed as a percentage or as millivolts per volt. In reality, what is measured is the apparent chargeability (Ma) which is the area (A) beneath the voltagetime decay curve over a defined time interval (t1 to t2) and normalized by the assumed steady-state t2 primary voltage, Vp, such that Ma = A/Vp = (1/Vp) × ∫ t1 of V(t)dt, in units of mVs/V.. 5.

(6) INSIGHT GEOPHYSICS INC.. Data Acquisition Data acquisition of the gradient and the Insight Section arrays are based on the principles of the Schlumberger array. In the Schlumberger array, a vertical geo-electric sounding is produced by expanding the current electrodes out from a centrally located pair of potential electrodes. As the Distance between the current electrodes (L) is increased, the effective depth of penetration is also increased, thus creating a geo-electric sounding curve.. The Gradient Array is a modified Schlumberger array which is best utilized for economically covering large areas. As with the Schlumberger array, the potential electrodes are always located within the boundaries of the two current electrodes. However, unlike the Schlumberger array, the current electrodes are placed at a fixed location (up to 100 times the potential dipole separation) and the potential electrodes are moved in a profile manner up and down lines between the current electrodes. Typically several lines can be read from a single transmitter placement. The effective depth of penetration can be approximated from Edwards(1977) where he defines the effective depth (Ze) between current electrodes separated by (L) as: ZE/L = 0.190 The results from the Gradient array are used to define the lateral boundaries of geo-electric anomalies. These anomalies can then be further detailed in a vertical dimension by surveying them with Insight Sections. The Insight Section is composed of a fixed array of potential electrodes (typically 40 with a potential dipole separation (MN) of 25 meters). The dimensions of the array are completely flexible pending the target depth and dimensions. Starting at the center location of the Insight Section, multiple current injections at various AB lengths are used to create vertical geo-electric soundings beneath each of the receiver potential dipoles. AB lengths used to create an Insight Section typically range from 5MN to 100MN. Data points are plotted directly below the center point of each potential electrode in the array. The estimated depth calculation for each plot point uses Edwards Ze estimation that has been further modified to reflect the reduction in effective penetration encountered as the position of any given potential electrode deviates from the center of L towards one or the other current electrode positions.. 6.

(7) INSIGHT GEOPHYSICS INC.. Instrumentation. ELREC PRO Ten channel IP receiver TECHNICAL SPECIFICATIONS • Input voltage: Max. input voltage: 15 V Protection: up to 800V • Voltage measurement: Accuracy: 0.2 % typical Resolution: 1 µV Minimum value: 1 µV • Chargeability measurement: Accuracy: 0.6 % typical • Induced Polarization (chargeability) measured over to 20 automatic or user defined windows • Input impedance: 100 MΩ • Signal waveform: Time domain (ON+,OFF,ON-,OFF) with a pulse duration of 500 ms - 1 s - 2 s - 4 s - 8 s • Automatic synchronization and re-synchronization process on primary voltage signals • Computation of apparent resistivity, average chargeability and standard deviation • Noise reduction: automatic stacking number in relation with a given standard deviation value • SP compensation through automatic linear drift correction • 50 to 60Hz power line rejection • Battery test. GENERAL SPECIFICATIONS. • Data flash memory: more than 21 000 readings • Serial link RS-232 for data download • Power supply: internal rechargeable 12V, 7.2 Ah battery ; optional external 12V standard car battery can be also used • Weather proof • Shock resistant fiber-glass case • Operating temperature: -20 °C to +70 °C • Dimensions: 31 x 21 x 21 cm • Weight: 6 kg. 7.

(8) INSIGHT GEOPHYSICS INC.. Walcer Model TX KW10. Voltage Input 125V line to neutral 400 Hz / 3 phase Powered by MG12, MG6 and MG12A Output 100 - 3200V in 10 steps 0.05 - 20 Amps Tested to 10.5 kVA Switching 1 sec., 2 sec., 4 sec., 8 sec. Metering LED for line voltage and output current Size 63cm. x 54cm. x 25cm. Weight 44 kg.. 8.

(9) INSIGHT GEOPHYSICS INC.. IP Parameters Transmitted Waveform:. Square wave @ 0.0625 Hz (4 second Square Wave) 50% duty cycle. Receiver Sampling:. Semi-Logarithmic windows (20 windows). Window M Delay 1 2 3 4 5 6 7 8 9 10. Width (ms) 160 80 80 80 80 80 80 80 80 160 160. Window. Width (ms). 11 12 13 14 15 16 17 18 19 20 TOTAL. 160 160 160 160 320 320 320 320 320 320 3680ms. Recorded Parameters IP measured parameter:. Chargeability in mV/V. Resistivity measured Parameters:. Primary Voltage in mV and Transmitted Current in mA.. 9.

(10) INSIGHT GEOPHYSICS INC.. SURVEY EXECUTION Generalities. Survey Dates:. Mobilize. Oct 21-22. Operate. Nov 7-20. Demobilize. Nov 30-Dec 1. IGI PERSONNEL: Blake McLaughlin Dylan Ryder Brydon Bigelow. Survey Coverage: Gradient Lines 0E through 3000E were surveyed using the gradient array. A total of approximately 27.8 line kilometres was surveyed.. Insight Section Survey Line. Start. 100E 400E 600E 900E 1100E 1500E 1700E 1900E 2100E 2400E 2600E 2900E. 450S 600S 450S 650S 600S 600S 600S 600S 600S 600S 600S 600S. Approximately 9.6 km of Insight Sections were surveyed. 10. End 450N 400N 450N 100N 150N 150N 150N 150N 150N 150N 150N 150N.

(11) INSIGHT GEOPHYSICS INC.. DATA PRESENTATION Quality Control and Processing The Insight Section Array utilizes a distributed array of 40 channels. Special attention is taken to ensure best possible contact resistance (k-Ohm) prior to acquisition. Approximately 10-15% of the data is repeated and saved in the field for quality control purposes. Particular attention is given to the time decay curves of the chargeability. The curves are monitored by the operator in real time while taking measurements in the field and every effort is made to ensure the maximum quality of decay curve is achieved. Decay curves are further analyzed by the processing department prior to producing final plots of the data using the Halverson-Wait model as a reference... Figure 4: Summary of Halverson-Wait(Anaconda) IP Model Theory: An application of Insight data through InDecay.. 11.

(12) INSIGHT GEOPHYSICS INC.. Apparent resistivity and total chargeability are calculated by the Elrec-Pro receiver. All receiver data is stored in the final data.csv file including all geometry points, primary voltages and voltage decays for further quality control and data reduction as required. Once the data has been quality reviewed and low quality readings rejected, a depth estimate calculation is made for the remaining data. The depth estimate is based on a uniform half space and does not account for resistivity changes actually encountered at surface or at depth. Changes in half space penetration resulting from the geometry of the receiver dipoles positions relative to transmitter dipoles positions are estimated.. All raw data was plotted using the Insight Section plotting presentation. Total chargeability calculated by the Elrec Pro Receiver is used as standard. Both chargeability and apparent resistivity may be culled for spurious effects resulting from noise or cultural effect. A non linear filter is applied to the Insight Section data. When applicable, Process InSndg may be used to remove these high frequency effects. All raw data is presented in *.csv format Depending on the surface conditions encountered on the property, the data will also be corrected for topographic and surface effects. The final reduced field data can then be inverted using the UBD-2D inversion program. Final inversions are an optional product to the client.. Loke, Dr. M.H.,Tutorial: 2-D and 3-D electrical imaging surveys ,Copyright 1996-2001. p. 24; 2.5.2 Tagg, Dr. G.F., 1964. Earth Resistances. P. 60. Typical Decay Curves Pistol Lake Project 60 50. mV/V. 40 30 20 10 0 1. 2. 3. 4. 5. 6. 7. 8. 9 10 11 12 13 14 15 16 17 18 19 20. 12.

(13) INSIGHT GEOPHYSICS INC.. Maps. Line 100E. Insight Section Apparent Resistivity and Total Chargeability. Scale 1:5000. 400E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 600E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 900E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 1100E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 1500E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 1700E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 1900E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 2100E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 2400E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 2600E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. 2900E. Insight Section Apparent Resistivity and Total Chargeability. 1:5000. Gradient Apparent Resistivity and Total Chargeability. 13. 1:5000.

(14) INSIGHT GEOPHYSICS INC.. Culture The property has a power line on it and is also cut by the Trans Canada Highway. Readings taken in the area of the power line and highway should be treated with caution.. Line 0 0 100 100 200 200 300 300 400 400 500 500 600 600 700 700 800 800 900 900 900 1000 1000 1100 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400. station depth culture 40 0 HWY 250 0 P-L -10 0 HWY 220 0 P-L -40 0 HWY 185 0 P-L -65 0 HWY 160 0 P-L -90 0 HWY 125 0 P-L -135 0 HWY 90 0 P-L -190 0 HWY 60 0 P-L -265 0 HWY 25 0 P-L -335 0 HWY 0 0 P-L -412 0 HWY -200 0 drill road -50 0 P-L -65 0 P-L -510 0 HWY -580 0 HWY -100 0 P-L -120 0 P-L -150 0 P-L -180 0 P-L -210 0 P-L -230 0 P-L -275 0 P-L -300 0 P-L -325 0 P-L -345 0 P-L -375 0 P-L -415 0 P-L -425 0 P-L -475 0 P-L 14.

(15) INSIGHT GEOPHYSICS INC.. 2500 2600 2700 2800 2900 3000. -485 -520 -550 -560 -600 -600. 0 0 0 0 0 0. P-L P-L P-L P-L P-L P-L. 15.

(16) INSIGHT GEOPHYSICS INC.. INTERPRETATION. Strong responses in the IP and resistivity parameters are evident on the project. Major resistivity low lineations have been interpreted to be shear zones. Many SW-NE and NE-SW striking inferred faults have been interpreted from the data. It should be noted that the inferred faults are not seen directly in the data but rather are inferred from truncations of other apparent resistivity and chargeability responses. A total of 13 anomalous chargeability anomalous trends have been interpreted from the gradient and Insight Sections. Golden share has provided Insight with a Total Field Magnetic survey collected by a third party and this data has been integrated with the IP results. Anomaly 1 Anomaly 1 is seen on lines 0E through 500E at approximately 263N and remains open to the west. To the east the anomaly is truncated by an inferred fault. The anomaly is a chargeability high associated with a resistivity high and strikes approximately E-W. A second sub parallel anomaly is present on lines 0E and 100E at approximately 300N. This anomaly is associated with a resistivity low. Both anomalies lie within a unit of increased magnetic response. Both anomalies are interpreted to be very close to surface; outcropping or sub-cropping.. Anomaly 2 Anomaly 2 is interpreted on lines 0E through 800E. The anomaly is a chargeability high in association with a resistivity high and is frequently broken by inferred SW-NE striking faults. The anomaly lies on the north flank of a magnetic high response. Interpreted depth to the anomaly varies between near surface and 100m.. Anomaly 3 Anomaly 3 is a chargeability high associated with a resistivity high on lines 100E through 400E near the southern boundary of the survey block at approximately 425S. There is no magnetic signature co relatable with the anomaly. Depth to the anomaly is estimated to be 50-100M. 16.

(17) INSIGHT GEOPHYSICS INC.. Anomaly 4 This anomaly is a strong chargeability anomaly associated with a resistivity low and is seen on lines 400Eand 500E to the immediate west of a very strong chargeability anomaly lying on the southern border of the survey area. The chargeability anomaly lies within or along the northern edge of a resistivity low lineament interpreted to possibly be a shear zone. The section on line 400 shows the anomaly is present near surface at approximately 337S and increases in response to depth. The anomaly correlates well with a magnetic low feature.. Anomaly 5 Anomaly 5 is present on lines 900E through 1400E at approximately 100S. The anomaly is a chargeability high associated with a resistivity high and lies to the immediate north of a resistivity low lineation interpreted to be a shear zone. The anomaly correlates fairly well with a magnetic high. Depth to the anomaly is estimated at approximately 50-100m Note that the close proximity of the power line to this anomaly has introduced some noise into the readings.. Anomaly 6 Anomaly 6 is seen on the north boundary of the property on lines 1400E through 1700E and is comprised to two sub parallel W-N-W striking chargeability highs associated with resistivity highs that trend off the survey area to the NW. Depth to the anomalies is estimated to be less than 25 meters, possibly outcropping. The anomalies are weakly co-relatable with an increased magnetic signature. Anomaly 7 Anomaly 7 is interpreted to be present on lines 1400E through 2700E. This anomaly is primarily a resistivity high lineation with a variable associated chargeability high signature. The anomaly is interpreted to be broken and offset by an inferred SW-NE striking fault near line 2300E. Depth to the anomaly is estimated at 50-75 meters. There is no associated magnetic signature with this anomaly Note that the close proximity of the power line to this anomaly has introduced some noise into the readings. 17.

(18) INSIGHT GEOPHYSICS INC.. Anomaly 8 Anomaly 8 is a very interesting chargeability high anomaly that correlates well with an interpreted Shear zone. The anomaly is present on lines 1700E through 2600E with the highest chargeability response occurring on lines 1700E through 2100E. In the 1700E through 2100E zone, the resistivity low representing the shear zone is no longer present, perhaps suggesting silicification of the shear in this particular area. Depth to the anomaly is estimated to be near surface to 25 meters The anomaly does not correlate well with the magnetic signature.. Anomaly 9 Anomaly 9 is present on line 1900E through 2300E at approximately 25S. The anomaly is a chargeability high in association with a resistivity low. Depth to the anomaly is estimated to be 25 to 50m The anomaly is weakly associated with a magnetic increase.. Anomaly 10 Anomaly 10 is a chargeability high associated with a resistivity high. It is present on lines 2500E through 3000E at approximately 113N and remains open to the east. Depth to the anomaly is estimated to be approximately 25 meters. The anomaly is weakly associated with a magnetic increase.. Anomaly 11 Anomaly 11 is seen on lines 2400E through 3000E and remains open to the east. The anomaly is not well represented in the gradient data but is much clearer in the section data surveyed on lines 2600E and 2900E. The Anomaly is interpreted to be cross cut by a SW-NE striking inferred fault at approximately line 2600E. Depth to the anomaly is estimated at surface to 25 meters. The anomaly my possibly outcrop on line 2900E at approximately 225S. There is no magnetic correlation with this anomaly.. 18.

(19) INSIGHT GEOPHYSICS INC.. Anomaly 12 Anomaly 12 is present on lines 1500 through 1900E and is a chargeability high associated with a resistivity high. The anomaly is interpreted to be broken by a NW-SE striking inferred fault at approximately line 1700E. Depth to the anomaly is estimated to be approximately 150m. There is no magnetic signature associated with this anomaly.. Anomaly 13 Anomaly 13 is only partially defined by the survey as it lies on the southern border of the survey area on lines 1600E through 1900E. The anomaly displays a very high chargeability values and appears to be associated with a resistivity high. Due to the incomplete response the depth cannot be estimated The anomaly may possibly be associated with a magnetic low.. 19.

(20) INSIGHT GEOPHYSICS INC.. Gradient Survey- Apparent Resistivity 20.

(21) INSIGHT GEOPHYSICS INC.. Gradient Survey-Total Chargeability 21.

(22) INSIGHT GEOPHYSICS INC.. Total Field Magnetic Survey with IP Interpretation Overlay (TFM Data Supplied by Golden Share) 22.

(23) INSIGHT GEOPHYSICS INC.. Insight Sections. 23.

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(29) INSIGHT GEOPHYSICS INC.. Conclusions and Recommendations. 1) Several resistivity low lineations are present striking approximately E-W across the survey area and are interpreted to be a shear zones. Breaks in the resistivity and chargeability measurements infer that multiple NW-SE and SW-NE striking faults may also be present 2) It is understood that existing trenching found on the property occur within or to the immediate north of the interpreted shear zone along a resistivity contact between the low resistivity shear to the south and higher resistivity measurements to the north. 3) Multiple chargeability high lineations are interpreted and are associated with resistivity high features, along resistivity contacts or resistivity low features. Most of the chargeability anomalies are present to the immediate north and south of the interpreted shear zones and tend to strike sub-parallel to them. The exception to this is anomaly 8 that correlates with an interpreted shear zone. 4) It is recommended that any available geologic or other geophysical information be compiled with the IP interpretation to assist in the prioritization of these anomalies. Drill testing can be done using a shallow hole to intercept the up dip edge of the anomalies. Pending results of the shallow hole, longer holes can be planned to explore the anomalies to depth. 5) Pending the results of the IP/geology compilation and preliminary drilling further IP work may be warranted to both the east and west as multiple anomalous trends remain open on both sides of the survey area.. Respectfully Submitted. Craig Pawluk Geophysicist Insight Geophysics Inc January 2012. 29.

(30) 705000.000000. 706000.000000. 707000.000000. ±. Pistol Lake Cut Grid UTM NAD83 Zone 15. 1183588. 4253559. L0+00E. 4246319 1188253. 1196407. TB36785. L30+00E. TB36794. TB36719. BL 0+00 TB36793. BL 0+00. TB36787. TB36784. 5392000.000000. 5392000.000000. 1183587. TB36791. TB36786. TB36790. TB36897. 3012220. TB36896. 4254311. TB36789. L0+00E. L30+00E. 5391000.000000. TB36778. TB36778. 705000.000000. 0 0. 3018513. 0.1. 0.2. 0.3. 0.4 Kilometers. 706000.000000. 707000.000000. 5391000.000000. 4218930.

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