MliV ^ PROJECTS UNIT. REPORT ON THE rielicopter-borne VLF AND MAGNETOMETER SURVEY IN THE ELLIOT LAKE AREA ONTARIO

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1 MliV ^ PROJECTS UNIT UNIT REPORT ON THE rielicopter-borne VLF AND MAGNETOMETER SURVEY ON BEHALF OF NORTH AMERICAN NUCLEAR LIMITED IN THE ELLIOT LAKE AREA ONTARIO by G O GEORGE W. SANDER, Ph.D., P.Er.g., THOMAS D. MOORE, B.Sc. FRANK G. KISS, B.SC. SANDER GEOPHYSICS LIMITED KANATA-OTTAWA, ONTARIO November 27, 1974.

2 INTRODUCTION A combined frelicopter-borne VLF and magnetometer burvey wa3 conducted on a group of claims in the Elliot Lake Area. Those claims are listed individually in the Annex of this report. All the claim groups for which the survey was conducted lie in the vicinity of the Elliot Lake orebodies. These orebodies occur in the lower section of the Proterozoic rocks close to the contact with the rocks of the Superior Province and the thickness of the Proterozoic rocks varies appreciable through the area. In the northern portion of the surveyed area, the claims cover almost the contact between the Proterozoic rocks and the underlying older Precambrian while in the southern portion, the Precambrian might be ft. below the surface. It was the purpose of the two geophysical surveys to gain detailed information concerning the depth and structure of the Superior rocks, the presence of dikes intruded into the Proter ozoic section. The magnetometer survey was intended to accomplish the first target while the VLF survey could be expected to solve the question of fault planes. Neither of the two methods are direct prospecting methods for the uranium deposits of the area, however, If one considers the considerable expense involved in drilling, it appeared to be well worth while to gain whatever structural information could be gained by geophysical methods.

3 J II ACCESS f, TOPOGRAPHY The area surveyed lies between the northern and central part of the Elliot Lake Basin. There are several access roads from the Town of Elliot Lake. GEOLOGY It is beyond the scope of this report to describe the geology of the Elliot Lake area in detail. Basically, the uranium bearing conglomerates occur in the lower section of the Proterozoic rocks. These Proterozoic rocks overlie the older Precambrian of Superior Province. The Elliot Lake Basin forms a large synclinal structure in which the older Precambrian outcrops in the north and south and is covered by throe to four thousand feet of Proterozoic rocks in the centre part of the basin. ' While at the present time only the Rio-Algom and the Denison Mines are producing, numerous indications of radioactive rocks have been found in the lower portion of the Proterozoic.rocks and it appears that the finding of additional orebodies will depend only on further exploration and on improvements in the price of uranium. Large zones of radioactive rock are known to exist and these might become orebodies with a higher price. There is every expectation that the value of uranium will increase over the next decade.

4 Ill INSTRUMENTS VLF SURVEY The VLF survey was conducted with an instrument developed by Sander Geophysics Ltd, for the use in the Company's helicopterborne survey system. The instrument consists of three mutually orthogonal coils which are permanently mounted in a fixed plane on the side of the helicopter. Any variations of this plane against the vertical direction are recorded by a vertical gyro giving pitch and roll of the aircraft. The information obtained from the three coils as well as the pitch and roll of the aircraft are recorded continuously by a digital magnetic tape recorder. In this way, movements of the aircraft can be monitored and if necessary, corrections can be applied to the VLF data for changes in the VLF field due to aircraft pitch and roll. The VLF system records the magnetic component of the VLF field in the direction of flight which corresponds to the main magnetic vector. In addition, the strength of the vertical portion of the field are recorded in the in-phase and out-of-phase components. Phase is determined in respect to the main horizontal vector. The field strength of the electromagnetic field under o right angle to the maximum coupled coil is also recorded in order to determine any deviation from the maximum coupled direction. Maps in this report were obtained by showing anomalies in the maximum coupled portion of the EM field representing increases in the total electromagnetic field and by relating this increase to the change in the phase of the vertical component. In other

5 IV words, the two components which form the elipses of polarization are shown at the maximum of each anomaly. The anomalies shown on the map indicate fault zones, strati graphic horizons and zones of low conductivity within the overburden. The VLF survey was conducted by using the VLF station at Guttler, Maine. This station is located to the east of the survey area and the magnetic vector of the electromagnetic field is polarized in the north-south direction. An electromagnetic field of this direction favours east-west striking conducting zone and consequently most electromagnetic anomalies must be expected to strike in the east-west direction. This is a direction of stratigraphic horizons in the Proterozoic rocks and many of the anomalies will either bo due to stratigraphic changes or to overburden changes which follow these changes.

6 V MAGNETOMETER SURVEY The magnetic data were obtained with a Sander NPM-4 nuclear precession magnetometer recording the total magnetic field. The magnetometer has an accuracy and resolution of approximately l gamma. Contour interval used for this survey was 20 gamma. The dirunal variations of the magnetic field were recorded with a Sander NPM-5 nuclear precession magnetometer. This instrument is basically similar to the NPM-4 magnetometer. It has a resolution of.1 gamma and an accuracy of better than l gamma. The ground station magnetometer took a measurement every minute and recorded it on magnetic tape. These recordings were used to correct the dirunal variations of the magnetometer survey and in this way a very precise magnetometer survey has been achieved. Corrections of dirunal variation and the magnetic contouring was done on Sander Geophysics's Texas Instruments 980A computer. The contour lines were drawn by hand. TECHNICAL DATA The survey was flown with a line spacing of 330 ft. or less. in such a way that each claim was given a minimum of one mile of flying. Survey height was generally between ft.. above the ground for the VLF system and 65 ft. lower for the magnetometer since the magnetometer sensor was carried 65 ft. below the helicopter. i Flight path recovery was partially done in flight, partially by the use of 16mm tracking camera. Data were recorded only in digital form during the flight, however, analogue records were run immediately after the termination of the flight in order to verify the geophysical data. These analogue records are available. l

7 VI RESULTS The results of this survey are shown on 6 maps. These maps are designated as Magnetometer and VLF survey maps. The map for VLF survey is still in preparation as well as the magnetometer maps for certain parts of the area. This report can concern itself only with the results of the magnetometer survey on the map of Twp. 143 and 144. Further reports will be issued when the other data are available, however, because of the urgency of supporting the survey for certain claims on which the assessment work is due now, this report was prepared early. The Magnetometer map for Twp. 143 and 144 shows gradual changes in the magnetic field from the north to the south being almost a concentric circle. These changes must be due to a deep seated magnetic body, such as a basic instrusive. The general pattern caused by the deep seated magnetic anomaly is interrupted by dikes which transgress the survey area in the east-west and in the southwest-northeast direction. These dikes indicate a much shallower depth for the magnetic disturbances which are intruded in the Proterozoic rock series. It should be quite possible to carry out detailed calculation for the deep seated body, however, it is not the subject of this report to carry out such calculation. The general location of these magnetic bodies are known from earlier, less detailed airborne magnetometer surveys but considerable more detail can be gained from the present survey.

8 VII PERSONNEL; The following people worked on this survey in the field: Thomas Moore, B.Se., Geophysicist, Frank Kiss, B.Se., Geophysicist, Brian Wilson, B.A., Pilot George W. Sander, Ph.D., P.Eng. Geophysicist and Supervisor. The office work for this survey was done by the following people: Thomas Moore, B.Se., Geophysicist, Ottawa, Ontario. Frank Kiss, B.Se., Geophysicist, Ottawa, Ontario. Audrey Innes, (Mrs.) Kanata, Ontario. George W. Sander, Ph.D., P.Eng., Geophysicist and Supervisor Dunrobin, Ontario. The survey was flown with a Bell 47G 3B2 Helicopter owned and operated by Sander Geophysics Ltd. under a Class 7 Licence.

9 F l G l LOCATION MAP NORTH AMERICAN NUCLEAR LTD. PROPERTY ELLIOT LAKE-BLIND RIVER AREA ONTARIO 1 ' /' ' V -* \ ' \ * 1* *~ -' 1 * ' ' Co.,,,,,*,- r-*.*,j..., \, r... Ui :, ,.-..'.., J...,,:.:.:- V...-., w:*,..;'.- /, T,Wf. i \:,. ua,,;t ; x "- ; *. 1 :;;^! ':/ ; ^^.K.^ ^ 1" '-, ;, JC -..,i.. u \ '-' ^^^, ^-. -"-' ;*^C-,oo! C" l'"-' G,,^ri, a :,,, (.. -' 't 'P. T. 'H ;."A, A v ^' - ' v ; J"' w ' /S : C)':, K ' G : - ^,-T J J *-.' '" ' "." ] s.,:.,.' ' J- v :.-,, -.-''^ ' - - l) 0 ' '-'. ',' f \. ' r - - C n '^ ' ' ' ' : ^ n' C 1.,-"^' \1 ( 'fl-^'^yf-.lr*". ' ""-"-- '" -S".-. "',--- f - Bl?,^! ""iv'i--''' 11 " ^ovj^''*- h ' J^" 1 ' /: 1 -Hr'" r''"m-^,,r ' 4*??^v "-!. ;' ^ Bio?K4,^' K ^ ' U1 ^ ;?4 v" ' '.^J^'ock'Z'v " i ', V, -, V0^1'*; '-, ^ -. * A-.;.-v ;- -- -~ '.'''" ",/-.'-. ' --,,\. ": 1*^"'!" i l fl '.ov ^.-i.v!-"r - J- f-m- : v ' ' /; w,.., U n l-tl;.,, i.)t.,jl, ' ' " ' '' '' S'J- '1- * '' ' -;0'-t' M 1 "**, ''* ''rf/ ' '. J "*~*^, '!. ' t..- ' f' *'n- 7 ~~^*~ ' ' ' ' ~* " \ ^ \ ( '' - ' ' 'v-, X..^ SCALE l"s 8 MILES

10 BOLGER OSO ADDITION TO THE REPORT ON THE HELICOPTER-BORNE VLF AND MAGNETOMETER SURVEY RECEIVED Ah'R PROJECTS UNIT, ON BEHALF OF NORTH AMERICAN NUCLEAR LIMITED IN THE ELLIOT LAKE AREA ONTARIO by GEORGE W. SANDER, Ph.D., P.Enq., THOMAS D. MOORE, B.Se. FRANK G. KISS, B.Se. SANDER GEOPHYSICS LIMITED KANATA-OTTAWA, ONTARIO January 28, 1975

11 This report relates to a number of maps submitted after the writing of the original repor*-, MAGNETOMETER MAP TWP.137 The claims covered by this magnetometer survey lie on the South East*rim of the Elliot Lake syncline and straddle the contact between the rocks of the Superior province and the overlying Huronian. The magnetic map indicates typical strong magnetic variations in the Superior province and a lesser degree of magnetic variations in the area to the North where the Huronian sediments increase in thickness. The contact zone lies somewhat to the South of the Serpent River'indicated on the map, one East- West striking magnetic anomaly lies to the North of the Serpent River, this anomaly represents basic intrusive rocks known to exist to the South of Batty Lake. The magnetic field to the North of the basic intrusives is considerably less disturbed. MAGNETOMETER MAP TWP. 149 Two claim groups were surveyed in Twp. 149, one under Elliot Lake including an island on the Lake. This area lies not far to the North of the South contact of the syncline, but the magnetic field is rather undisturbed in this area. A small claim group in the North Western corner of the Twp. is situated in the Central part of the Elliot Lake basin. Magnetic variations are somewhat stronger in this area indicating the presence of basic rocks in the Huronian sectionv

12 VLF MAPS TWPS. 143 S 144 The VLF anomalies are shown as symbols indicating current concentrations in the ground detected by the VLF survey. The symbols identify the amplitude and phase relationship of the EM anomalies. A number of East-West striking anomalies are indicated on the map, some of these follow lakes and might be due to the glacial clays which cover the bottom of the lakes in the area, however quite often lakes follow shear zones which give rise to VLF anomalies. Since the shear zones also create topographical lows with clay cover, the effect of the two causes is hard to separate. In any event, structural information concerning the Huronian section can be obtained from the VLF survey. The direction of the primary electromagnetic field emphasizes East-West trending anomalies and these are predominant on the survey. The anomalies should be investigated in relationship to known geological features in the Huronian and identified as to the cause or relationship to fault zones. VLF MAP TWP. 137 A number of East-West striking VLF anomalies are showr. on the map. These anomalies follow often topographical features, however they extend beyond the topographical features and there is much reason to believe that the anomalies are caused by the geological features which are expressed also by the topography.

13 VLF MAP TWP. 149 VLF anomalies in Twp. 149 indicate East-West trending zones of current concentrations. Since the Southern portion of the map is underlain by Elliot Lake, identification of the anomalies might be difficult except by extrapolation to the shore. Yours very truly, GWS/ai George W. Sander

14 LIST OF CLAIMS SSM ^ J SSM

15 Ontario Ministry of Natural Resources Lands Administration Branch Projects Technical Assessment Unit Work Credits File Recorded Holder Township or Area Gaiashk (Twp. 137) Joubin (Twp. 143) Buckles (Twp. 144) Gunterman (Twp. 149) 9M TnunsHi nfi ( ' 'u 1S51 Type of survey and number of Assessment days credit per claim Mining Claims Geophysical Electromagnetic, 55.days SSM to 40 inclusive Magnetometer.days to 78 " Radiometric -. days Induced nolarization.days to 28 Section 86 (18) M.days Geological m..days Geochemical, Man days D. days Airborne to 08 " to 17 Special provision f.j Ground D to to 51 " (O Notice of Intent to bo issued: to 85 " D Credits have been reduced because of partial coverage of claims. CD Credits have been reduced because of corrections to work dates and figures of applicant. C] No credits have been allowed for the following mining claims as they were not sufficiently covered by the survey: to 02 " to to inclusive to 64 " The Min^g Recorder may reduce the above credits if necessaiy in order that the total number of approved assessment days recorded on each claim does not exceed the maximum allowed as follows' Geophysical 80; Gr-ological 40; Geochemical 40; : FormtA. 101(10/74)

16 BEANGE Tp (M.I604) l Tp.'15* ) SCAL ir^-j; 1..,: " s- PATENTED CHO** LEASES ticciic or MHtlf* F^ l Iff B V^^'V ^W W -.ww'.s i *SM 11 (H i HW i 'i ro*iii MARSH O* MuMk -?-: ;i Mines i MINING LAND *. DATEOFISSU O/C TOWNSITE e. MINISTRY. ( I56^S7 FILE Vi OFHAtUMLRESOUftta McGiverin Twp. (M. 1311) OM^KIO MINISTRY OF NATURAL RESOURCE SURVEYS AND MAPPING BRANC

17 LEHMAN TP (M.-I2I3).THE TOWNSHIP GAIASHK, (Tp. 137) \ 1 40*0*.40*0* a* o DISTRICT Of ALGOMA v. r 3\ r M w ;^. MINING DIVISION,. ^.** -. k.'7 -; - SCALE: 1 -INCH 40 CHAINS!J -r? ; ' LEGEND i MI S -,^*;'^ -* 5 '. Y~" ' V ' -i.. : *V. ^ v * *j PATENTED LAND ^ \ ' "' ' fc 1. ^ * CROWN L AND SALE 'K 'l:'.**"" " J,' 1? LEASES ' i ' 4,.. v /. i-, ',,y - ^ LOCATED L ANO.^,, LICENSE OF dt'cyp ^ '- : l MINING R IGHTS O NlV SURFACE RIGHTS OKI** ' J v- ^- R *0. l *s.. -. Lji*i- - ROADS IMPROVED ROADS KING'S HIGHWAYS V RAILWAYS POWER LINI I^ARSH Ofl MUSKfft x -t ^, *X*. /.* ; *j/ ^ r MINES i J 'lv S ' ' ' '. :^^^g**1 -^T.',, ' j\ *i- s- 1-';^.^'. ' - * fr r ~" * ^"^^^ O DC UJ O T l*- ' l - ' ' a * j ' -; '''^'? DAT! OF ISSUE APR30W5 ^ OFNAIUMLRUOURCtt PLAN NO M.-12,12 41JC8NW8C BOLGER 210 Deagle Twp. (M.-750) MINISTRY OF NATURAL RESOURCES SURVEYS A ND MAPPING B RANCH

18 UGHSON Tp, M.I2I7 THE TOWNSHIP ' OF BUCKLES (Tp 14 ;...f";*, **-^' DISTRICT ALGOMA SAULT e^ MARIE - ~ ' MINING DIVISION B, SCALE:MNCH*4O CHAINS -LEGEND ^ "XT -V j \ l - J l *,,*-, ^-C/ PATCNTCD LAND CROWN LAND SAfcC LEASES OCATED LAND LICENSE OF OCCUPATION MINING RIGHT* ONLY SURFACE RIGHTS ONLY ROADS IMPROVED ROADS KING'S HIGHWAYS RAILWAYS POWER LIN*S MARSH OR' MUSKEG MINES CANCELLED Mli* ' rlfb ^\ M. NOTES ^ '. rz^:'i..-i- -. -f-.-i.--!-.--.^ 400' Surface Rights Reservation around oil Lakes and Rivers. This Twp lies within the IMPROVEMENT DISTRICT of ELLIOT LAKE By Order Of The "Ontario Municipal Board Dated 29 August, A D, ^ K u,, -~ r^erw,., cxswt!* '0^4 T- ". V-^- Sand and gravel rn all unpatenled mining claim* m this Twp reserved to i he c ro*r ME PC reserved for proposed ''jns me for claims S.84IOI - 84I02 ara 7i956 oct 29,^'t* C -:' M. 256 V oiso clams S 84103, , b C48S - MINING LANDS 4 DATE OF ISSUE APR MINISTRY Of NATURAL RESOURCES PLAN NO.-M.I2I6 41J03NWd030 eet8 BOLGER JOUBIN Tp M MINISTRY OF NATURAL RESOURCES SONvt-i AN: v A ' N r, SK-NLH

19 Bouck Tp (M.-I2I9) :? THE TOWNSHIP OF GUNTERMAN (Tp. 149) r*. J X r-hr~ T* " L , L- l- f ^f -H c t J^T.*- -,Lc! *~* i DISTRICT OF 1 ALGOMA SAULT STE. MARIE MINING DIVISION SCALE:HNChN4O CHAINS LEGEND l ll*bifkt.fti* [--4V l a" ' s*..xsii20* f PATENTED LAND CROWN LAND SALE LEASES LOCATED LAND LICENSE OF OCCUPATION MINING RIGHTS ONLY SURFACE RIGHTS ONLY ROADS IMPROVED ROADS KING'S HIGHWAYS RAILWAYS POWER LINES MARSH OR MUSKEG MINES CANCELLED PATENTED MINING RIGHTS ONLY NOTES i- 400' Surfoct Rights Rtwrvolton olonfl tht thorn of all lakes and rivtrs. ' * /* i -?r -h^^t'w;\ti-fj -w" MM* 5*37a Mire 3!-,., s " \ l'tu04]u c f l Xbi.,. J c. J* 8!* 2 *W"^ snaak *W"^ r. fifr^* ' ^IfSSVf t i i 1 fvtuan S* ^JL- JK.X 66*34 8SS4T *^47 C This Twp. lies within th* Improvement DMrtct of Elliol LoM ^^ Surface Righis patented for orea 1,2,3,469 to Elliot Lake Townsite. Original ihorellni of port of Crotch Loke filled with mine fallings shown thus -... Areas withdrawn from t taking unoler Section 43 of rhe Mining Act. (R.SO. 19TO) File Date Dlsposltton tl/t/tf M.H.O, (W \ S * * Ofc x ^ov'wti f oiyju... \ ts ""v PL A N WO.-M. l J08NWe(i) BOLGER 330 Esten Tp. (M.-792) MINISTRY OF NATURAL RESOURCES SURVEYS AND MAPPING BRANCH

20 ra * o GUNTERMAN TP M.I2I8 o m en CD C O x m CO O) GAIASHK TP M S'S CO x -o CO o o I o x i z CO Se 2 i li * P S m 5 0 < m 2 o o c S 52 2 O S Q om 3 < 3 I i z So m 5 2 c o "" 5 i o g rt - c z z to o o F l e * ^ ffi TJ > 6 o (O m 8 i 31 i O O o m m M rn B Sfi a a T^ T > > o o m m O 5 en I O w z o 2 O M O CO T) O O) 3 o o n O D O m w m O s I i m CD Q o 2 2 S I* z o3d Z S CO m O m z o Z o O) O O DO

21 NORTH AMERICAN NUCLEAR LIMITED HELICOPTER BORNE GEOPHYSICAL SURVEY FLOWN AND COMPILED BY SANDER GEOPHYSICS LIMITED OTTAWA 1974 SCALE = 800 FEET IOOO IOOO V L F ANOMALY PERCENTAGE I NCREASE IN TOTAL S IGNAL RATIO OF V ERTICAL IN PHASE TO VERTICAL 56/3 OUT OF PHASE SIGNAL 9 VARIATION LOCATION O F ANOMALY K FIDUCIAL POINTS BLOCK 5 District of ALGOMA Township 149 H B S 2 ro Or rv ro CD 01 N CD BLOCK-6 District of ALGOMA 41J88NWe BOLGER 250 Township 149

22 Jlfc. S SM-1 7p, District of ALGOMA tit "" Township _ ~ M 41J88NW0a3a BOLGER S60 V L F ANOMALY NORTH AMERICAN NUCLEAR LIMITED FLOWN AND COMPILED BY PERCENTAGE INCREASE IN TOTAL SIGNAL 56/3 RATIO OF VERTICAL IN PHASE TO VERTICAL OUT OF PHASE SIGNAL VARIATION HELICOPTER BORNE GEOPHYSICAL SURVEY BLOCK l SANDER GEOPHYSICS LIMITED OTTAWA 1974 LOCATION OF ANOMALY 456 -H 460 X FIDUCIAL POINTS SCALE l FEET IOOO IOOO 200O 3OOO

23 !t"l ^ i" iffi '-e- /w ' * "4 s B JU ^*C,.i WN'.fiS*f± l VLF ANOMALY, PERCENTAGE: INCREASE - IN TOTAL iiignal RATIO OF vi. IN PHASE TO VERTICAL OUT OF PHASiI SIGNAL VARIATION LOCATION OF ANOMALr 820* BLOCKS 2, 384 NORTH AMERICAN NUCLEAR LIMITED HELICOPTER BORNE GEOPHYSICAL SURVEY District of ALGOMA Township 143 S 144 SCALE l"* 800 FEET FLOWN AND COMPILED BY SANDER GEOPHYSICS LIMITED oi E - ro oi QCH3