REPORT ON GEOPHYSICAL SURVEYS. ASTA AND RITA CLAIMS Nanaimo Mining District NTS 92L1 Latitude 58' 08'N Longitude 126O 12'W for FALCONBRIDGE LTD.

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1 REPORT ON GEOPHYSICAL SURVEYS ASTA AND RITA CLAIMS Nanaimo Mining District NTS 92L1 Latitude 58' 08'N Longitude 126O 12'W for FALCONBRIDGE LTD. Vancouver, B. C. November, J. L. Lebel, P. Eng. MPH Consulting Limited

2 TABLE OF CONTENTS PAGE 1.0 INTRODUCTION 2.0 PROPERTY DESCRIPTION, LOCATION AND ACCESS 3.0 INSTRUMENTS AND SURVEY PROCEDURES 3.1 HLEM Survey 3.2 VLF-EM Survey 3.3 Magnetic Survey 4.0 PRESENTATION OF RESULTS 5.0 RESULTS AND DISCUSSION 5.1 HLEM Survey 5.2 VLF-EM Survey 5.3 Magnetic Survey 6.0 CONCLUSION 7.0 RECOMMENDATIONS REFERENCES STATEMENT OF QUALIFICATION STATEMENT OF COSTS FIGURE 1 Location Map 2 Claim Map 3 HLEM Profiles hz 4 VLF-EM Profiles 5 Magnetic Profiles 3 4 back pocket back pocket back pocket I

3 1.0 INTRODUCTION This report presents the results of horizontal loop electromagnetic (HLEM), very low frequency electromagnetic (VLF-EM) and magnetic geophysical surveys conducted by Marston Geophysics Limited on behalf of Falconbridge Limited in the Adams River Area, Vancouver Island. claims. The surveys covered parts of the ASTA and RITA mineral The designation Grid D was used to distinguish the surveys from other surveys conducted in the area. The purpose of the surveys was to locate geoelectric and geomagnetic features indicative of massive sulphide mineralization. The focus of the work in this particular area was based on the results of an airborne electromagnetic survey flown by Dighem Limited on March 4 and 5, 1984 for Falconbridge Limited. A short line of reconnaissance VLF-EM was conducted prior to the surveys to establish the optimum location for the grid. The surveys were conducted between the period September 3 to 15, 1984 by M. Rogers, J. Ashenhurst, R. Gibb and S. Kemp of Marston Geophysics Limited.

4 2.0 PROPERTY DESCRIPTION, LOCATION AND ACCESS This property is composed of the ASTA and RITA mineral claims comprising 20 units each for a total of 40 units (Figure 2). Status of the claims is as follows: No. of Record Anniversary Claim Units No. Area Date ASTA h Nov. 15, 1984 RITA h Nov. 15, 1984 The claims are located on Vancouver Island in the Nanaimo Mining Division on NTS map 92L1, at latitude 58' 08'N, longitude 'W approximately 62km west of Campbell River (Figure 1 ). Access to the property is gained from Sayward via the MacMillan Bloedel, White River main line to the Moakwa and Gerald main lines which lead to a network of local logging roads in the area. Station line 12+00E, 34+00N of Grid D is situated close to the ON, 2E and OS,2E location posts of the ASTA and RITA claims, respectively.

5 YUKON TERRITORY Figure I FALCONBRIDGE LOCATION MAP LIMITED 1 R-t IOm 098, 099 rr' 1 : 7,920,000 mr kr(yh I Omto. Nov., km MARSTON GEOPHYSICS LTD.

6 Kokummi Mtn. Adams River Area Nanimo Mining District, B.C. N.T.S: 92 L/I E

7 3.0 INSTRUMENTS AND SURVEY PROCEDURES 3.1 HLEM SURVEY The HLEM survey was conducted with an Apex Max Min 11+ electromagnetic system with a coil spacing of 100m. Four frequencies, namely 222hz, 444hz, 888hz and 1777hz were employed. Readings were taken at 25m intervals on lines spaced 200m apart. Stations of the grid were installed at 25m intervals along the topographic slope. Slopes measured between the stations during the VLF-EM survey were used to calculate the actual distances between the stations so that the distance between the transmitter and receiver could be kept at a constant 100m. The slope infoma- tion was also used to calculate the slope between every 5th station so that transmitter and receiver could be appropriately inclined to maintain the coplanar coil configuration required for a HLEM survey. A total of 5.7km of surveying was carried out. 3.2 VLF-EM Survky The VLF-EM survey was conducted with a Geonics EM-16 receiver tuned to the transmitter station, designated NLK, located at Seattle, Washington. Readings were taken facing toward the northeast. Valid anomalies, I therefore are indicated by relative positive to negative inflections in the in-phase dip angle data considered in a south to north sense.

8 A total of 6.7km of coverage including readings taken along the tie line of the grid was effected. 3.3 Magnetic Survey The magnetic survey was conducted with a Scintrex MP-2 total field proton precision magnetometer. Readings were taken at intervals for a total production of 6.7km. Diurnal variations in the geomagnetic field were monitored (and subsequently removed from the survey results) using a GEM solid state memory base station magnetometer.

9 PRESENTATION OF RESULTS The results of the surveys were compiled in ' stacked' profiles for each of the surveys in the field. I For the purposes of this report the results are illustrated in plan profile format at a scale of 1 :2,500. The results of the HLEM survey, the VLF-EM survey and the magnetic survey are illustrated in Figures 3, 4 and 5. Station spacing was corrected for slope and plotted on the maps at true horizontal distances. The topography shown was compiled from the slope informatioh taken during the VLF-EM survey and adjusted to a 1 :10,000 scale topographic map from which physiographic features shown were also extracted. Profile scales for the various surveys are as follows: HLEM Survey lcm = 10% VLF-EM Survey: lcm = 10% Magnetic Survey: Icm = 50 gammas In the case of the HLEM survey only the data from one, i.e. 888hz, of the four frequencies is presented. The results of the magnetic survey are presented in profile format rather than contoured format because the wide 1 ine spacing makes contouring somewhat subjective. The in-phase dip angles of the VLF-EM survey were processed using the Fraser Filtering technique (Fraser, 1969). The results (positive values only) of this operation are annotated, where appropriate, along the 1 ines

10 5.0 RESULTS AND DISCUSSION 5.1 HLEM Survey The HLEM survey recorded a number of anomalies on the grid. The location of the cause of each anomaly is shown by a 'bar' where the length of the 'bar' reflects the interpreted width of the cause of the anomalies. Interpreted depth, (in m. ), conductance (in mhos), and dip of the cause of each anomaly is annotated beside each feature. The dip shown reflects the actual dip of the feature rather than the dip relative to the topographic slope determined from the results. Interpretations were accomplished using interpretation diagrams for the HLEM method compiled by Nair et a1 (1968). In spite of the wide line spacing, a number of the anomalies correlate from line to line to indicate a number of conductors on the property. Conductors are labelled alphabetically from A to F for discussion purposes. Conductor A Conductor A extends from line 10+00E to line 18+00E at about 38+00N. Although no complete anomaly was actually registered on line 16+00E, the existence of the conductor is suggested by anomalous readings recorded at the very end of the 1 ine. Coverage on 1 ine doesn ' t extend far enough to the north to determine whether this feature 1 continues uninterrupted across the grid.

11 The conductor is thin, in a geophysical sense and varies in depth from. - 50m on line 10+00E to 15m on line 16+00E. Conductance of the conductor decreases from 56 mhos on line 10+00E to 2 mhos on line 18+00E. Dip of the feature appears to be subvertical which equates to a steep dip to the north considering the south facing slope on this part of the grid. Note that on lines 10+00E and 14+00E the conductor's anomalies are only partly defined because of limits to the survey coverage, so that, the ultimate character of the feature at these locations is not disclosed. Conductor B Conductor B extends between lines 14+00E and 20+00E at about 36+00N. It is open to the west. Its anomalies reflect a modest 10 mho conductor at depths of up to 2%. The conductor is narrow except on line 14+00E where a width of approximately 20m is indicated. Dip of the feature appears to be subvertical with respect to the topographic slope which equates to an actual dip of 70' to 80 north. Conductor C Conductor C occurs on lines 10+00E and 12+00E at about 34+50N. This conductor is a narrow, high conductance feature situated at depths of 15m (line 10+00E) and 35m (line 12+00E). On 1 ine the assymetry of the shoulders of its anomaly indicate a gentle north dip. On line 12+00E a steep dip to the north is indicated.

12 Conductor D Conductor D. consists of a wide (25m) zone on line 16+00E which appears to bifricate into two narrow conductors Dl and D2. Conductor Dl extends from line 16+00E to line and continues off of the grid. D2 is evident on line 18+00E but terminates somewhere between lines 18+00E and 20+00E. Conductor D represents a shallow low conductance feature except on line 20+00E where depth and conductance are interpreted to be 40m and 56 mho, respectively. Dip of the conductor appears to be to the south at a relatively steep angle except on line 16+00E where it may have a dip of 5@ S. Conductor E Conductor E represents a thin, poor quality conductor which extends from line 16+00E to 18+00E and off the grid to the east. The anomaly caused by Conductor E is not we1 1 defined because it is incorpor- ated into the anomaly caused by Conductor D. Conductor F Conductor F represents the most impressive feature detected by the survey. It crosses lines 10+00E to 16+00E and likely continues to line 20+00E where an anomaly was partially defined before steep terrain limited survey coverage. Note that the VLF-EM survey supports the contention that Conductor F traverses the entire grid. Conductor F is either a wide feature up to 75m wide as indicated on line 12+00E or two narrow features which are too close together to be resolved by the loom coil spacing used.

13 The VLF-EM survey appears to indicate two narrow features although the anomalies observed may also represent the edges of a wide conductor. On lines 14+00E and 16+00E the anomalies associated with this conductor are only partially defined. Interpretation of the anomalies on lines 10+00E and 12+00E assuming two narrow conductors are present indicates high (38-56 mho) conductances, depths of 15-25m, and moderate south dips. Several single line anomalies were recorded by the survey. feature are listed and described as follows: 5.2 VLF-EM Survey 10+00E, 28+00N - 28 mho and at a shallow (15m) depth - the dip of this feature is not apparent because the anomaly is only partially defined 10+00E, 30+25N - Mainly an out-of-phase anomaly indicative of a shallow low conductance conductor These 10+00E, 36+50N - primari 1 y an out-of-phase anomaly indicative of a poor conductor 18+00E, 39+75N - an anomaly which is only partially defined because of limits to the survey coverage 20+00E, 29+25N - probably caused by Conductor F but only partially defined because of limlits to the survey coverage The VLF-EM survey outlined a number of anomalies as indicated by open circles on Figure 4. No hnalysis of these anomalies was undertaken because the VLF-EM method is not particularly amenable to quantitative interpretation. 1

14 The topographic response consists of negative in-phase dip angles on the north facing slope and positive in-phase dip angles on the south facing slopes. This situation arises because the primary field eminating from the transmitter station follows undulations in the topography. The overall impression given by the results, particularly for those anomalies located in the valley in the middle of the grid where topographic responses are relatively minor, is that the conductors dip with a subvertical attitude. 5.3 Magnetic Survey, The results of the magnetic survey vary by only about 200 gammas $cross the property. In terms of general variations only one feature appears to show any line to line consistency. This feature which occurs at the south ends of lines 10+00E through 16+00E consists of a general decrease in the geomagnetic field in a south to north sense, the inflection point of which occurs at approximately 34+00N. The cause of this gradient is not known. It may represent a geological contact which based on the gentleness of the gradient must occur at an appreciable depth. This type of response is also consistent with the topography found in this area of the grid. Detailed variations in the geomagnetic field vary considerably from line to line. For example, anomalies of about gammas located at 10+00E, 38+25N and 18+00E, 38+00N are not manifest on adjacent lines 12+00E and 16+00E, respectively. Similarly the ' step' 1 i ke anomaly located at 20+00E, 35+75N is not repeated on 1 ine 18+00E. 1

15 Two 50 gamma anomalies located at 20+00E, 34+25N and 18+00E, 34+50N may be caused by the same magnetic feature. The strike of this feature, however, differs from the trend of nearby HLEM conductors. Coincidence of magnetic and electromagnetic anomalies is often considered to be favourable in massive sulphide exploration. The magnetic anomaly may be caused by pyrrhotite, thereby enhancing the possibility that the conductor is caused by sulphides as opposed to graphite which is non-magnetic. In several instances magnetic and electromagnetic association is observed on the grid. Examples occur at: 20+00E, 34+25N (Conductor Dl ) 20+00E, 29+25N (Conductor F where both the magnetic and electromagnetic anomalies are poorly defined because of limits to the survey coverage); 14+00E, 31+50N (Conductor F) and 10+00E, 38+25N (Conductor A). Note that in most of these examples the magnetic anomalies are restricted to portions of the conductors indicating that the conductors are not uniformly magnetic throughout their length.,

16 6.0 CONCLUSIONS The HLEM and VLF-EM surveys outlined a number of conductors on the property. The causes of these conductors and their significance cannot be ascertained on the results of the electromagnetic surveys alane. In a number of instances the conductors occur at the limits of the survey coverage where steep terrain impeded the progress of the HLEM survey. The magnetic survey outlined a number of anomalies which do not correlate from line to line. magnetic conductors. Some of these anomalies correlate with the electro- None of the conductors however, exhibits a magnetic signature along its entire strike length. Based on the results of the geophysical surveys there do not appear to be any worthwhile drill targets on the property.

17 7.0 RECOMMENDATIONS The results of the geophysical surveys should be compared and correlated with any other geotechnical information, such as geology and geochemistry available from the property. If any encouragement ensues from the above exercise, then consideration should be given to conducting fill-in geophysical lines at loom intervals to resolve the conductors in more detail. For the wide conductors, particularly Conductor F, described, detailed HLEM coverage with a shorter coil spacing is required to determine whether one wide or two narrow conductors are present. If any of the electromagnetic conductors located at the extremities of the grid prove interesting, the HLEM survey converage should be extended if it is physically feasible. MPH CONSULTING LIM~TED

18 REFERENCES FRASER, D.C., 1969, Contouring of VLF-EM data. Geophysics, v. 34, pg NAIR, M.R., BISWAS, S.K., IMZUMDAR, K., 1968, Experimental studies on electromagnetic response of ti1 ted conducting ha1 f-planes to a horizontal 1 oop prospecting system. Geoexplor., v. 6, pg

19 STATEMENT OF QUALIFICATIONS J. L. LeBel 436 W. 6th St. North Vancouver, B. C. V7M 1 K9 Education B.Sc M.Sc Geological Engineering (Geophysics Option) Faculty of Applied Science Queen ' s University Kingston, Ontario Geophysics School of Graduate Studies University of Manitoba Winnipeg, Manitoba Employment Experience May Senior Geophysical Operator December Gulf Mineral s 110 Yonge Street Toronto, Ontario - conducting, compiling and reporting on scintillometer, electromagnetic and magnetic surveys March December Junior Geophysicist Scintrex Surveys 222 Snidercroft Road Concord, Ontario - conducting and compiling airborne electromagnetic, ground electromagnetic and IP/resistivity surveys

20 Employment Experience (cont. ) April November 1981 Staff Geophysicist Amax Minerals Exploration Thurlow Street Vancouver, B. C. - planning, supervising or conducting, compiling, interpreting, and reporting on numerous airborne and ground geophysi cal surveys throughout North America and the U. K. December Senior Geophysical Consultant present MPH Consulting Limited Granville Street Vancouver, B.C. V6C IT2 - planning, supervising, interpretiing and repopting on geophysical surveys in a consulting capacity Professional Affiliations Association of Professional Engineers of B.C. Society of Exploration Geophysicists B.C. Geophysical Society

21 STATEMENT OF COSTS WORK DONE: HLEM Survey 5.7km VLF-EM Survey 6.7km Magnetic Survey 6.7km Reconnaissance VLF-EM Survey 1.525km WORK PERIOD: September 3-15, 1984 EXPENDITURES: HLEM Survey $600/km VLF-EM Survey $ 65/km Magnetic Survey $ 65/km Reconnaissance VLF-EM Survey TOTAL