GEOPHYSICAL REPORT ON AN INDUCED POLAR.IZATION SURVEY

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1 GEOPHYSICAL REPORT ON AN INDUCED POLAR.IZATION SURVEY T & V Claim Groups some 12 miles Northwest of Babine Lake, B.C. Latitude 55' 26'N Longitude 126' 35'W AUTHOR: Glen E. White, Chief Geophysicist,a, P. ENGINEER: W. G. Stevenson (- 2' [u DATE OF WORK: May 11 - June 7, 1971

2 CONTENTS PAGE Introduction... 1 Location and Access... 1 Property... 1 Survey Specifications The Survey Grid The Induced Polarization Survey... 2 Data Presentation... ;...,... 2 Discussion of Results Conclusion & Recommendations Instrument Specifications - Induced Polarization Unit... 6 Certificate Glen E. White, Chief Geophysicist... 7 W. G. Stevenson, P. Engineer... 8 ILLUSTRATIONS h Figure 1 Location and Claims Map 1/~i~ure 2 Induced Polarization-chargeability 5 Figure 3 Induced Polarization-resistivi ty Interpretation Map t Figure

3 - Shore Creeks Paved H/ghwoy Line # Rivers I Area Surveyed Department of Mines and Petroleum Resourcc ASSESSiAENT REPOST d T.V.I. MIN NORTH BABINE PROPERTY LOCATION AND CLAIMS MAP SCALE: LOCATION MAP: 1" = 80 MILES APPROX. - CLAIMS MAP: I" =12@00 FEET APPROX.

4 INTRODUCTION * During the period May 11 to June 7, 1971 inclusive, Tri-Con Exploration Surveys Ltd., on behalf of T.V.I. Mining Ltd., conducted a program of induced polarization surveying on the "T" and "V" claim groups located some 35 miles east-northeast of the village of ~akelton, B.C. and some 12 miles northwest of Babine Lake, Omineca Mining ~ivision, Province of British Columbia. The purpose of the induced polarization survey was to examine several geochemically anomalous areas by the induced polarization method to try and delineate any chargeable bodies which may possibly be caused by sulphide mineralization. A crew of six men were employed in establishing grids on the geochemically interesting areas and conducting the ensuing induced polarization program. LOCATION AND ACCESS The 'IT" and "V" groups of mineral,claims, owned by T.V.I. Mining Ltd,, are located some 35 airmiles east-northeast of Hazelton, B.C. and some 12 miles northwest of the head of Babine Lake, latitude 5' 26'N, longitude 126' 35'W, N.T.S. 93~110. Access to the property is by four-wheel-drive road to the head of Babine Lake and then by helicopter; direct access to the property is by helicopter from Smithers, B.C. PROPERTY The mineral claims covered completely or partially by the induced pol- arization survey are listed as follows: "V" claims 3-6 inclusive "TI' claims 11, 13, inclusive and 30. SURVEY SPECIFICATIONS The Survey Grid The survey grids were established coincident with the induced polarization survey and consisted of northeast-southwest lines turned off at

5 right-angles every 400 feet from a northwest-southeast directed baseline. The traverse lines were numbered at 100 foot intervals. A total of 6000 line feet of baseline and 61,300 line feet of survey grid were chained, slope-corrected, cut and flagged. Some 11.4 line miles of induced polarization surveying were conducted. The Induced Polarization Survey The induced polarization survey was conducted with a Hewitt 1KW I.P. transient pulse type unit deployed in the Wenner electrode configuration with an "a" spacing and traverse interval of 200 feet.' In the pulse (also known as time domain) method a steady direct current is impressed into the ground for a few seconds, abruptly terminated for a short time (usually equal to the length of pulse time) and then a steady current is impressed in the reverse direction for a few seconds and then abruptly terminated for a few seconds. This is one cycle which can be repeated. A fraction of a second after each cessation of the current pulse the decay voltage is integrated and measured. The current and total integrated primary voltage and total integrated decay voltage are then recorded for the given number of cycles. From these three measurements the chargeability in millivolts/volt and apparent resistivity in ohm-feet are calculated. The values calculated are then plotted at the center position of the array for a given set of readings. Data Presentation The survey data accompanies this report as contour maps, at a horizontal scale of one inch equals 400 feet as follows: Figure 2 Induced Polarization; Percent chargeability (millivolts/volt) contoured at an interval of 1 mv/v. Figure 3 Induced Polarization; Resitivity contoured at an interval of 100 ohm-feet. Figure 4 Interpretation Map

6 DISCUSSION OF RESULTS The induced polarization data has been correlated with B.C. Department of Mines and Petroleum Resources Aeromagnetic Map 5263G and reconnaissance geochemical data described in a geochemical-geological report dated October 30, 1970 by G. L. Anselmo et el. The topography of the areas surveyed vary from swamp to moderately steep. Outcrop occurs frequently on the T-grid, while the V-grid appeared to be completely overburden covered. The resistivity data, Figure 3, in general shows only moderate changes in resistivity which can be attributed to variations in the conductivity of the overburden, and in the overburden depth. The resistivity data on the "V" claim group varied from a low of 135 ohm-feet to a high of 472 ohm-feet which would possible indicate deep overburden conditions. The resistivity data on the "T" claim group, on the otherhand, varied from a low of 87 ohm-feet to a high of 1906 ohm-feet and shows two areas of high resistivity data which likely reflect shallower over- burden conditions. The chargeability data, Figure 2, on the "V" group shows two relatively strong NW-SE trending chargeability highs which reach a peak of some 10 mv/v above a background of some 2.5 mv/v. To aid interpretation of the induced polarization data the contour values from the airborne magnetometer data, shown on Map 52636, have been superimposed on the area surveyed as illus- trated in Figure 4. From this data it can be seen that the chargeability contours in general, parallel the magnetic trends. Detail induced polar- ization surveying with 100 and 300 foot "a" spacings along line NW from SW to NE indicated possibly deep overburden conditions since the 100 foot "a" spacing showed no anomalous response. The 300 foot 11 II a spacing on the otherhand, indicated a definite increase in chargeability material per volume with depth. Correlation of the reconnaissance geochemical data with the induced polarization data showed that the copper and zinc geo- chemical trends are in a more north-south direction, almost perpendicular to the gentle slope direction. Thus should they possibly be caused by an ion distributing source associated with the anomalous chargeability data, the geo- chemical trends may possibly reflect zones of higher permeability in the over- burden.

7 The chargeability data from the "T" claim group showed several areas of anomalous response which in two cases reached a high of 10 mv/v. The anomalous chargeability values in claims T 27 and T 29 appear to be coincident with areas of higher resistivity whereas the chargeability high areas in claims T 13, 26, 28 and 30 occur in areas of low to moderate resistivity values. Interpolation of the airborne magnetometer dad over this area (Figure 4) indicates that the induced polarization trends do not appear to show any correlation with the magnetic trends, though a large magnetic high does occur just off of the survey area to the southeast and the chargeability data appears to be increasing in intensity in that direction. The reconnaissance copper and zinc geochemical data did not show any particular correlation with the induced polarization data. CONCLUSION An induced polarization survey was conducted over portions of the T and V mineral claim groups on behalf of T.Y.I. Mining Ltd. Two interesting chargeability high trends were located on the V claim group which parallel the trends of the regional airborne magnetic data and which appear to be increasing with depth as indicated by a limited amount of detail induced polarization surveying. Reconnaissance geochemical surveying within this area located only weak copper and zinc geochemical values which trend at a 45 degree angle to the anomalous chargeability trends. Several interesting areas of anomalous chargeability data were delineated on the T claim group. However, there appears to be no correlation between these anomalous and the weak reconnaissance copper and zinc geochemical value obtained in the 1970 soil sampling program. RECOMMENDATIONS (1) Conduct a limited amount of detail induced polarization surveying on both the V and T claim groups with larger "a" spacings to test the chargeable bodies to depth. (2) Obtain a magnetic profile over the same lines on which the detail induced polarization survey is completed such that the magnetic and chargeability responses can be correlated.

8 3. Conduct a small amount of stream sampling in the main creek on the T claim group to test seepages from the direction of the induced polarization anomalies for any indication of copper or zinc min- s eralization. Respectfully submitted, TRI-CON EXPLORATION SURVEYS LTD. Glen E. White B.Sc., Chief Geophysicist

9 INDUCED POLARIZATION A Instrument APPENDIX Instrument Specification (a) Type - Trabsient Pulse Prospecting Equipment (b) Make - Hewitt Enterprises 200 (c) Size - 13Y1W x 15%"L x 9%" Deep B Specifications (a) Transmitter 1,000 Watt nickle cadnium battery supply operation mode 2 seconds on, 2 seconds off, 2 seconds reverse 4 seconds on, 4 seconds off, 4 seconds reverse Cycles.5, 1, 2, 3, 4. selected on switch Timing - solid state logic circuitry Current Ranges 10, 50, 100, 500, 1000, 5,000, milliampere Solid State dv and I.P. solid state memory storage dv ranges 10, 50, 100, 1,000, 1,500 millivolts I.P. ranges.l,.5, 1.0, 5, 10, 15, millivolts Self-potential-direct dial reading from polartometer A.C. filtering-low pass active filter Transient delay period.4 seconds Integrating period 1.2 seconds Power supply-four 9 volt transistor radio batteries C Survey Procedure (1) Wenner, pole-dipole or schlumberger array D Data Presentation (1) chargeability percent chargeability in milliseconds or millivolts volt (2) resistivity - ohm-feet (3) self-potential-millivolts often not used

10 CERTIFICATION TO WHOM IT MAY CONCERN: I, GLEN ELMO WHITE, of the City of Richmond in the Province British Columbia, hereby certify: That I am a Geophysicist and reside at Gilbert Road in Richmond, B. C. That I studied Geophysics and Geology and graduated from the Un- iversity of British Columbia with the degree of sachelor of Science. That I have been engaged in Mining Exploration for eight years. That I do not have, nor do I expect to receive, either directly or in- directly, any interest in the T or V mineral claims or in the secur- ities of T.V.I. Mining Ltd. That this report is based on information derived from an induced pol- arization survey carried out by Tri-Con Exploration Surveys Ltd. under my supervision. Dated this - 28 day of - June 19a. Glen E. White, B.Sc., Chief Geophysicist

11 CERTIFICATE I, William G. Stevenson, DO HEREBY CERTIFY: - That I am a Consulting Geological Engineer with offices at Suite 209 Stock Exchange Building, 475 Howe Street, Vancouver 1, B.C. - That I am a graduate of the University of Utah, 1946, with a B.Sc. Degree. - That I am a registered Professional ~n~ineer the Association in British Columbia. - That I have practised my profession for 22 years.. - That I have no direct, indirect or contingent interest in the T or V Mineral Claims or in the securities of T.V.I. Mining Ltd., nor do I intend to receive any such interest. - That I have reviewed a report dated June 28, 1971 based on work conducted by Tri-Con Exploration Surveys Ltd. under the supervision of Glen E. White, Chief Geophysicist. DATED at Vancouver, British Columbia, this day of 5u W. G. STEVENSON & ASSOCIATES LIMITED Consulting Geologists

12 3+00 SW 2+00 SW I +oo SW RESISTIVITY ohm - feet CHARGEABILITY millivolts/ volt. a = apparent depth in test. Baseline

13 L E G E N D - Creeks Shore Line Cff/vem Areo Surveyed Department of +-+ Mines and Petroleum Rssl - a mwa*m" LTD. Filr: Fig. I C7 Ant h---- " ^champlrr Junr 1971 h

SUMMl'l WlLS LIU. GEOPHYSICAL REPORT. W. CT. a~evenson Y I

SUMMl'l WlLS LIU. GEOPHYSICAL REPORT W. CT. a~evenson Y3 qi@, 1970. I 2-90 9 CONTENTS - PAGE Introduction... 1 Property... 1 Location and Access... 1 Survey Specifications Survey Grid... 1 Induced Polarization