COBALT PRODUCTS LTD. BUTLER LAKE ASBESTOS DEPOSIT RENNIE TWP. SUDBURY MINING DIVISION ONTARIO MAGNETOMETER REPORT R. A. GEISLER. ?3 l.

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1 42B05NW SAI RENNIE 010 COBALT PRODUCTS LTD. BUTLER LAKE ASBESTOS DEPOSIT RENNIE TWP. SUDBURY MINING DIVISION ONTARIO MAGNETOMETER REPORT by R. A. GEISLER?3 l JUN 20 io-,e RESIDENT GEOLOGIST SAULT BTE. MARIE

2 f*.vl!si-*r*l rf(s*-v'-vj ^ i.:'. ".'''."-". ' yllftf S^^'*'' W :!: ' : '":'.-: -' '^ : ;.' MAGNETOMETER REPORT /* 4 \ ' ^During the month of February 1952 a magnetometer survey was ' ; carr ied out f or Cobalt Products Ltd. on 10 mining claims east corner of Rennie Twp. Sudbury Mining Division, Ontario. The magnetometer survey described in this report was undertaken to trace and delineate a serpentinized pyroxenite intrusive rock bearing chrysotile asbestos veins up to i inch. The initial discovery was made on the north west shore of Butler Lake by Jack Tremblay while prospecting in the area for gold and base metals just prior to 1940* This occurrence of asbestos was examined by Albert Hopkins in September of and in his report on it, the recommendation was made that a magnetometer survey be carried out to find the extent of the serpentinized pyroxenite in which rock the chrysotile asbestos occurs. Field tests made on material from the discovery pit showed that the magnetic susceptibility of the serpentine bearing the asbestos was of a much lower order than the serpentinized pyroxenite. This observation suggested that any drill holes testing the magnetic high over the serpentinized pyroxenite should be continued into the areas of lower magnetic intensity as the asbestos bearing rocks carried little magnetite in the samples tested. It is also possible that a serpentinized dunite horizon might exist beneath the waters of Butler Lake and form a sill of which only the serpentinized pyroxenite out crops. This serpentinized dunite horizon if present is considered in other areas as a most favourable host rock for asbestos deposits. SUMMARY The magnetic survey of the 10 mining claims in Rennie Twp. revealed a number of anomalies that are considered to represent three or more rock types. The anomalies all trend north-easterly paralleling Butler Lake. Anomalies "AM, "B", and "C" are all thought to be closely related and have been intruded by three parallel Keweenawan diabase dikes. The presence of these diabase dikes is regarded as favourable as they suggest that the ultra basic intrusive has been subjected to fracturing. Anomaly "A" and "Bn have a combined strike length of 2800 feet with a width varying from 100 to 500 feet. The asbestos discovery pit is located midway along the 2SOO foot length on the south side of the anomaly. Anomaly "C" is considered an extension of anomaly WAW. Anomalies "D" and "E" may be possible off-shoots of the basic intrusive and in the present program no exploration work is recommended on them, pending exploration results from

3 and WBW. Anomaly nf w on the east shore of Trem take/ has? not been fully outlined and the geology should be ; mapped in detail in this area when conditions permit. Anomaly "G" in the east^corner of the area surveyed occurs in an area of abundant hybrid granite outdrops and the section should be geoligized at the same time that the "F" anomaly is examined. Anomaly "H" is a low oi'der negative one and outlines the Algoman granite intrusive mass. An initial diamond drilling program to consist of 2 drill holes totalling 1500 feet has been recommended to appraise the major anomalies "A" and "B" in the vicinity of the asbestos discovery pit and in an area close to the diabase dikes that intrude the intrusive. No work is recommended at this time for anomalies t C n, "D", "E", WF W. no n, as the outcrops in or close to these anomalies should be first mapped before further decisions are made. No exploratory diamond drilling has ever been carried out on this property. LOCATION. ACCESSIBILITY AND EXTENT OF PROPERTY The mining claims are all located in one continuous group in the northeast corner of Rennie Twp., Sudbury Mining Division, Northern Ontario. From Missinabi the property can be reached by airplane by flying to Conboy Lake and taking the portage to the property from Conboy Lake to Butler Lake, The property can also be reached by car and canoe by taking the Renabie road as far as Rennie Lake and thence by canoe across Rennie Lake, thence to Garvey Lake, Trem Lake and Butler Lake. The complete list of the mining claims covered by the survey is given in the appendix to this report. GENERAL GEOLOGY The geology of Rennie Twp. in the vicinity of the mining claims under discussion, is shown on the Ont. De pt. of Mines map number 51G of the Rennie - Leeson area. This map shows the claims to be underlain by granite, hybrid granite, and some volcanic rocks, intruded by three Keweenawan diabase dikes. The map does not show the serpentinized pyroxenite outcrop area on the north shore of Butler Lake, owing to the fact that at that time a beaver dam on this lake had raised the water level to cover this rock. The water level has since been lowered by the removal of this dam exposing part of the serpentinized pyroxenite sill* Approximately 400 feet east of the asbestos discovery pit where the serpentinized pyroxenite outcrops have been exposed by the lowering of the water level, there has been found P large block of pyroxenite float having thread veins of chrysolite asbestos.

4 frmf&a^.^^t:^ "-'-'--v:; ;-.TP"V-vr.: ' '.'-.' -- v-''..*\ : --'-:-^'.--. -" '-'-'-^ ' '?#~s-tetpti vicinity of the asbestos discovery there has been pit sunk a;few feet from the lake shore. In this pit,. j up to ^ inch or more occur across a width of feet. -The serpentine appears to strike N.E. - S.W. paralleling the lake and dips steeply to the S.E. The local geology;is described in more-detail in the report by Albert Hopkins. RESULTS OF THE SURVEY All the field measurements for the magnetic survey are plotted on the accompanying map drawn to scale of l inch * 100 feet* Contours of equal vertical magnetic intensity have been drawn at intervals of 10,000, 7000, 6000, 5000, 4000, 3000, 2000, 1000, 500, 400, 300, 200, 100, O, and -100 gammas. Beside each measurement station the magnetic value is shown in relation to the base station located at 14 NE, 4NW whose magnetic value was arbitrarily chosen as 345 gammas. Magnetic anomalies "A", "B", "C", "D", "E", "F", "O", and "H", have been marked on the accompanying map, and the approximate position of the 3 Keweenawan diabase dikes has also been shown* Technical details regarding the procedure followed in performing the survey will be found in the appendix to this report. DISCUSSION OF RESULTS Anomalies "A". "B", and "C n having a total strike length of approximately 2800 feet with a width varying from 100 to 500 feet are considered to be caused by a magnetite bearing serpentinized pyroxenite intrusive rock. Along this strike length of 2800 feet there is only one small known outcrop area of serpentinized pyroxenite. This small outcrop area occurs in the approximate center of the 2800 feet and is also the site of the discovery pit showing chrysotile asbestos associated with the serpentine. It is to be observed that the asbestos discovery pit is located on the southern side of the anomaly, and it is quite possible that the serpentinized pyroxenite sill may have a serpentinized dunite differentiate v/h i eh would life under the waters of Butler Lake. In other mining areas the serpentinized dunite is usually regarded as the most favourable host rock for chrysotile asbestos deposits. For this reason a drilling program testing the high anomalies caused by the magnetite in the serpentinized pyroxenite should be extended into the 500 to 1000 gamma anomaly area as this fringe area might be an asbestos bearing horizon.

5 -.may be offshoots from the ultra ^ investigation, of anomalies ; "D" and "E 11 should anomalies^?a" and "B 1! have been explored. ^.. Trem Lake;would appear /to be located in a greenbuit'crop" area and" this section should be geologized to iilrie thet \nature*of;the anomaly. Anomaly "G" occurs in ah area in which there are numerous rugged outcrops bf hybrid granite" and this section should be examined in detail in,conjunction with the work on anomaly WF". Anomaly "H" is a low order negative anomaly which fairly outlines the extent of the Algoman granite intrusive. The three Keweenawan'dikes.that intrude the anomalous zones at right angles, have been plotted partly from-outcrops and partly inferred from the results of the survey. On line 52NE, and 300 feet SE of the Base line, there is a reading of 500 gammas which suggests the possibility of the occurrence of an anomaly contiguous with the main anomalous zone. Further magnetic work to the northeast might disclose the beginning of such an additional anomaly. This work would only be carried out if the exploration effort on the "A" and "B" anomalies are successful. RECOMMENDATIONS Anomalies MAM, "B rt, and ncn are considered from an economic viewpoint to represent the best exploration bet on this property as together they give an approximate length of 2600 feet of favourable eerpentinized ultra basic intrusive rock in which a drilling program could outline a commercial deposit of dhrysotile asbestos. The recommendation is therefore made that an exploratory diamond drilling program consisting of 2 holes totalling 1500 feet be carried out to appraise the adbestos content of the ultra basic sill as outlined in the survey. The two drill holes have been plotted on the map to test anomalies "A" and "B" near the asbestos discovery pit and in close proximity to the diabase dikes. The drill holes should be drilled south easterly as shown, and at an angle of -45, thus they will go out under the waters of Butler Lake. When conditions permit, the geology should be mapped in the section M nn who where f o anomalies nnnmol'iab "fi" "D", "Rtl ME', HtJMt "F", ^ anh and W "O" fit Viovo have Koon been outlined. ;y?.:

6 ygg^a&g&stis-xiy ^.v - - ^,;i.e-^*r*;ci,,~(.i1-. j**e\? ^^m^mm^^ f&^&mw rapkl-s' Ji^^?;S;}^:i-'*'.v,-'"-'-,'" ;'-'.v ; :. "A',.. ; ^...-.'. W?,. Ill- 'DETAILS OF THE MAGNETOMETER SURVEY fss^sl:-'': '.y?- -t- V ;^'?-;;:'iirea^;*liir*tit Area Surveyed i ; The complete magnetic survey of the Butler Lake mining claims covering the asbestos discovery in Rennie Twp., included in whole or in part 10 mining claims located in the north east corner of Rennie Twp., Sudbury Mining Division, Ontario. An..area of approximately 210 acres was covered by the survey. The following claims were covered In whole or in part by the survey: S58559; S58560; S58561; D890; S60893; S60894: S60895; S60896; S60897; Period of Survey The geophysical survey commenced on the Butler Lake claims of Cobalt Products Ltd. on February 11, 1952, and all field measurements were completed by February 25, Calculation, plotting, drafting and report was completed in Toronto, Ontario, during the period March 15 to April 15, Personnel All magnetic field measurements were taken by R.A. Geisler and H.L. Banting. Mr. J. Tremblay acted as chief line cutter, assisted by W.P. McDonough, T. Fletcher and R.A. Geisler. 4. Picket-line Mileage During the course of the magnetic survey in the month of February 1952, 9*5 miles of picket line wore cut and chained. In the east corner of the area surveyed extreme topography conditions and deep snow greatly reduced the speed of the line cutting and instrument work. 5. Topography The section in the vicinity of Butler and Trem Lakes in 'he central part of the area surveyed, was comparatively flat with the outcrop ridges approximately feet above the lake level* In the east corner, elevations above the lake in the outcrop area, rise to some 200 feet above the lake level.

7 m ^^m^^^i^^- V** ^3C-WV8?4*frV'"- ''^' *-'- 1 ' -'- " ; * '-' i ' '-v ^m^m^^^^^ - :::- j^s^g^ ^i^vfiiv,:;?v. 4-i',^'-*-'' ''' ; : -- of -Measurement Stations of stations for the survey consisted in a ifof numbered pickets, placed 100 feet apart along picket ^running north west and south east at 200 foot intervals, which lines were at right angles to a selected base line on Butler Lake and striking north-easterly, parallel to the shores of the/lake. All picket numbering was referred to the south west end bf the base line which for this survey was given a co-ordinate center of O - O feet. Although directions as herein given, refer to the true direction of the base line (north east, - south west) and the cross-lilies (north west - south east) for the sake of clarity in the field work, the actual inscriptions on the base line pickets merely show OE, - IE - 2E... 52E, while in the case of cross lines, inscriptions on the pickets read IN... 6N. for north westerly directions above the base line, and IS, 2S etc. for south easterly directions below the base line. 7. Classification of Magnetic Measurements 8. Magnetometer Survey Base Stations 2 Stations of Main Network 633 Check Measurements on leases 20 Check Measurements on Independent Field Stations 10 Total Measurements Performed 655 Field readings were taken with a vertical Magnetic Force Variometer (Watt), measuring the variations of the vertical component of the earth's magnetic field. A scale constant of 25.0 gammas per scale division was used throughout the survey. All plotted gamma values for the individual stations were referred to an arbitrarily chosen magnetic base station located at 14NE - 4NW, with the arbitrary value of 345 gammas to which all field measurements were tied. Diurnal magnetic variations were reduced to a minimum by re-reading a magnetic base station approximately every two hours and the average error calculated from the ten check measurements on independent field stations showed the survey to be accurate to within t 9 gammas. Respectfully submitted, 9.A. Geisler April 15th, 1952.

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11 Gemma value of vertical magnetic intensity. Vertical magnetic intensity of greater than 5000 gammas. "-..i Trail, portage. of 1000 to gammas. April Ist ^ -too l. l l i t - -J c - \ 7 i i COBALT PR MAGNETON BUTLER LAKE SURVEY DISCOVERY RENNIE TOWNSHIP ONTARIO Scale -1 inch to 100 Feet S-5856/ /\ 1^ ~ 7 Claim posts. Contour of equal vertical magnetic in tensity-gjm mas. Vertical magnetic intensity of 2000 to 5000 Vertical magnetic intensity Reading station on picket line. -M-, 12E; 40E By ft. A. Get's fer S wamp with boundary. Vertical magnetic intensity o f O to IQtfO gammas. Approximate location of Picket line numbers. Vertical magnetic intensity of O to-300 gammas Keweenawan diabase dike. Proposed diamond drill hole. A, B, etc. A nomalies. 42B05NW AI RENNIE 200 ;''^^^'^