Norman Paterson (Se Associates Limited

RECEIVED

42A10NW8585 2.1285 DUNDONALD 010 A PR 1 Q 1Q7^

PROJECTS SECTION

REPORT ON

ELECTROMAGNETIC SURVEY

CLAIM GROUP 'D*

DUNDONALD TOWNSHIP f CONCESSION 3, (NORTH HALF),'

LOTS l AND 2 PORCUPINE MINING DIVISION ONT.

FOR

ASARCO EXPLORATION COMPANY

by

NORMAN PATERSON S ASSOCIATES LIMITED Toronto, Ont. January. 1973.

-1 ~ Norman Paterson (Se Associates Limited

l. INTRODUCTION

This report describes the results of an extra low

^frequency- (ELF) electromagnetic survey carried out for

Asarco Exploration Company by Norman Paterson and Associates

Limited of Toronto. The purpose of the survey was to prospect

for massive sulphides. The ELF instrument was selected for

this purpose because of its ability to penetrate thick layers

of conductive overburden which are known to overlie the

property.

2. THE PROPERTY'

The property is a group of eight claims^ lying in the

north half of Concession 3, Lots l and 2 in Dundonald

Township, which is in the Porcupine Mining Division, Ontario.

The claims which were surveyed are registered under the numbers

255718 to 255720, 292198, ^92989, 293649, 293650, and

293672 are owned by Asarco Exploration Company Limited,

44 King St. West, Toronto, Ontario. Access is by Highway 67

which cuts through the grid some three miles south-west of the

village of Porquis Junction, as shown on Figure 1.

3. GEOLOGY

The claim group is covered by heavy overburden and

the geology in detail has not been observed. Projection of

available mapped geology would suggest the group is underlain

by basic intrusives and/or volcanics of Archean age. This

has been confirmed by six holes which show mostly basic

intrusives in the form of peridotite and one occurrence of

gabbro. One hole shows volcanics in the form of andesite and

rhyolite. No economically significant sulphides were reported.

- 2 - Norman Paterson fe Associates Limited

The Alexo deposit just to the south of the property

contains nickel and copper sulphides. The mineralization

occurs in the peridotites close to the contact with andesites.

4. PREVIOUS WORK

^Surveys were carried out on the property in 1952

by Noranda Mines Limited, but the file on this work could

not be located in the O.D.M. assessment files. Magnetic and

Scintrex SE-300 and SE-200 vertical loop EM surveys were

carried out on the western 3/4 of the property in 1964 for

Alsof Mines Limited. Additional magnetic and Turam EM surveys

were carried out on the entire property by Geosearch Con

sultants in 1971. Except for a weak SE-200 anomaly, no

electromagnetic anomalies were observed. A prominent

magnetic anomaly occurs in the centre of the property. This

anomaly was drilled in 1964 by Alsof Mines Limited and found

to be caused by a peridotite intrusive. No sulphide minerals

of any importance were discovered.

The decision to conduct the present low frequency

EM survey was based on the possibility that the Turam instrument,

with a relatively high transmitter frequency, and the SE-300

and SP]~200 instruments, with relatively narrow coil separations,

may not have penetrated the 200 to 300 feet of overburden

on the property.

- 3 - Norman Paterson ft Associates Limited

5. SURVEY SPECIFICATIONS

a) Instrumentation

The equipment used on this survey was the Geonics

PJM-25 system with a frequency of 50 cycles per second. A

large Turam type t "r^n am-i t-1--in g loop is used to energize the

survey grid. The receiver measures the inclination and

ellipticity of the ellipse of polarization, values which may

be related directly to the in-phase and quadrature components

of the horizontal secondary field produced by a buried conductor,

The inclination is measured in degrees and is accurate to

h degree. The ellipticity is measured in per cent and is

accurate to h o f l per cent.

The EM-25 method de-emphasizes poor conductors such

as clay beds, water field shear zones and other electrolytic

sources. It also responds poorly to weakly connected or

disseminated mineralization thus producing a low overall

geological background. Good conductors, such as those

typical of massive sulphides will respond to the method and

their recognition is aided by the low geological background.

A practical lower limit to the detection aperture

with this method would be a conductivity-width of about 15

mhos. Most massive sulphide deposits are well above this

level, generally exceeding 50 mhos. Conductive overburden on

the other hand, seldom exceeds one to two mhos.

Some topographic effect is obtained with the EM-25.

Changes in elevation of the order of 20 to 50 feet can produce

in-phase errors of a few per cent. However, the quadrature

response is unaffected by topography and this type of error

can be distinguished from the response of true conductors

by the lack of quadrature response. Both the quadrature

-4 ~ Norman Paterson & Associates Limited

and. in--phase response increase nearly linearly with increasing

distance from the transmitting loop by an amount that depends

on the conductivity and thickness of the overburden. This

.linear effect can readily be subtracted from the data.

b) Procedure

In this survey, the large loop configuration was used.

The positions of the two loops are shown in Figure 2. A

total of 7.0 line miles were surveyed, in which 388 stations

were occupied at a station interval of 100 feet. Noise from a

60 cycle power line made 12 stations unreadable..

~ 5 - Norman Paterson fe Associates Limited

6. SURVEY RESULTS

a) Presentation

The survey results are presented in Figure 2 in the

form of stacked profiles at a map scale of l" to 200 feet.

The profiles are plotted at a scale of l" to 10 per cent

or 10 degrees. This is twice the normal plotting scale in

order to accentuate any weak anomalies. Unfortunately it also

accentuates the natural system noise associated with this

instrument and therefore may not be an improvement.

In order to relate the data to a datum line more

easily, a straight line segment of background equal to about

3 degrees per thousand feet away from the transmitter loop

was removed from the in-phase profiles. The same process

was applied to the quadrature data, using about 4^ per cent

per thousand feet.

b) Interpretation

Part of the survey area is severely affected by

interference from 60 cycle noise from power and telegraph

The effect was to produce either a signal that could

not be read or an anomalous departure from smooth background.

Lines 24E to 36E north of the power line were strongly affected and

very little useful information could be obtained. The power

line produced a marked negative anomaly, particularly on the

quadrature response south of the power line. This is very

noticeable east of Line 36E. The negative quadrature trend

on these lines may also be caused by a change in overburden

conductivity or depth which should be corrected for by a

second degree background correction, instead of the linear

correction used. In any case no anomalies are seen in this data.

To the west of Line 24E the data is less affected by

external noise and the profiles are smoother. No significant

anomalies are seen in this data.

— ft — Norman Paterson St Associates Limited

7. SUMMARY AND CONCLUSIONS

1. An extra low frequency electromagnetic survey was

carried out over the property under discussion using

the fixed transmitter method.

2. Interference from power and telegraph lines on the

grid interfered with some of the data producing both

unreadable signals and spurious anomalies.

3. On the rest of the grid, no significant anomalies

were observed and thus no recommendations are made for

additional development work on the basis of this

survey.

Respectfully submitted, NORMAN PATERSON S ASSOCIATES LIMITED

U

Roger K. Watson,B.A.Se.,P.Eng, Geophysicist

••'•'•" V (':

Figure l

LOCATION MAP

GROUP Dr^ ^

Scale: l'50,000 NTS.-42 A/10

'—/•'/ v~ X.--'-' .s-'~ ' V i -, v j , . -'"" -.--'"V"^-' :-:--; ., \ ^.. i : .

c**

42A10NW8585 2.1305 DUNDONALD 900

TO BE ATTACHED AS AN APPENDIX TO TECHNICAL REPORTFACTS SHOWN rfERE NEED NOT BE REPEATED IN REPORT

TECHNICAL REPORT MUftT CONTAIN INTERPRETATION, CONCLUSIONS ETC.

Type of Survey Township or Claim

Electromagnetic EM-25

Author of

Total Miles of Line cut

line cutting) for first survey.ENTER 20additional si same grid.

Magnetometer.

HATR- H fly

PROJECTS SECTION Res. Geol. ___

i

Previous Surveys

gw

. Approved by.

Approved by.

Lsarco Exploration Comoanv of Canada- 44 King St. W., Toronto, Ont.

R. K. Watson- 401 Bay St. , Toronto, Ont.Survey Sept. 23,flQ72 - Peh. 7, 1Q7-*

(linccutting to office)pr,,t 8 miles

VISIONS 13™ AUESTED r J., . , /feTcktnViPx l \t ————— Geophysical S \ \ " ; J

—Electromagnetic. *P , .j /As (includes V S 1 1\ , f ; t -Magnetometer-X-^^ S 11

i ~ ,-n1*^ 1 7 —UaHintnptrir ^ ^

( 1s for each -Other ———————————— ̂ - ^:y Using Or.lr.aira! f\ ^ '

-Jk* •'^ V^JG^A^h^mir,.! ..7—., 0 ^ '

DITS (Special provision credits do not apply to airborne surveys^-TpCfc'f

F.]prf"'Tiapnptir Rarlinrnptrir(enter days per claim)

T-fc ^ 1 1 .?siON[A rrT^RP'' \J^ "O^oLA^^JLV,Author of Report or Agent

TONf OiialifjratipNQ #^ . l^r^Tf

4 ilLlfa '~ *, y j? \n til i t- ^A i X X y l n\sfrst'\ q (f Sty /""-fii "6***3Js***~*A OuJLt^f C\-.C,.X-t.^ L̂^tt^r^f -^--*vt--.>ovvxJL r y v tt^Q'AfuVr\CJ^aC^cn?d'

RAMr.H

rt o 4- r*

HANP.H

rlatp

MINING CLAIMS TRAVERSEDList numerically

p J?5573iJ5 '(prefix) (number)P 255719 ,

P 255720

p 292198

J p 292989,

P 293649 .......................,.......................................P 293650,

\scs\ * *yjo/*.p-...^...........................................

V^jytxCo-pv ci/ l?^|pirvj

1 i i m *jr v j i/ '^1 W^r^v

^^...^J...........................................\.S4?r,.,,,.,,,,.,..,................,,...f . . - . -- '

TOTAL CLAIMS 8

Show instrument technical data in each space for type of survey submitted or indicate "not applicable"

GEOPHYSICAL TECHNICAL DATA

GROUND SURVEYS

Number of Stations______3RR____________________Number of Readings____375 Station interval———HUH____________________________________________ Line spacing___4np '________________________________,————————.————. Profile scale or Contour intervals Profile l" g 10*

(specify for each type of survey)

MAGNETIC

Instrument.Accuracy - Scale constant— Diurnal correction method. Base station location.—-—

ELECTROMAGNETIC

Instrument______GeonJCS E.M. 25____Extra Low FrequencyCoil configuration Orthognal

Coil separation Variable——Amirary In-phase to 1/2 degree, out-- nf phqge fcp . 1/2 . t-CV.1% -———— ———— -——— Method: E Fixed transmitter O Shoot back d Inline D Parallel lineFrequency 50 cycles per secon^ -————-——.———,.^-^.---——-—^— ,^-^—.-—----——-^—1— —--————-—

(specify V.L.F. station)Parameters mpasnrprl Tilt- nf ppi gyj zatT-lon gllipsg (In^phasg) j Elllpticity _____

(Quadrature)InstrumentScale constant.Corrections made.

Base station value and location.

Elevation accuracy———————————————INDUCED POLARIZATION - RESISTIVITY

Instrument—————^^.—-.——^--..——.--.Time domain——————————————————————————— Frequency domain. Frequency____________________________ Range———————Power™.^^^—-—---^^^————---—————--—-——-—.—..^^—-——.^^-———..-——.Electrode array-— Electrode spacing. Type of electrode.

TWf TOWNSHIP Qf

Mf C A RT TWI? - M.

BISTRfCT- Of

PORCUPINEMIHJNG O iWSION354624 l 1(334622

— -1326D6 . j

CROWN LAND S AU

RIGHTS ONLY

'S HIGHWAYS

MfcRSH.

MINI S3Z6486 j 352 585L . L ' -L^—* ^ f—* —* —*- -y-- f^^^^

75881 70q*0 .., w , L— —-.u—x;

l L,House \ L103586 'l 403589

*T

,^Hsurface ngm r art terttis and

M***

:'-;^UI;,!M^^

L 0 1\2 S * '"Flooding nghts on freserved to H .EPf^^ contou^ ele. 903'

7IOtfl j 71016 MJtO l (D H.flO-—t^T—i—I03S48 103541 10354O 10*559 J

v^ S P.O. reserved tor files 39684,

Area marked thus l Park S ite.103851 103650 I03B49 ! 103548

IOS56S (37l3fi8 371367 l 371366 371365.., _ —*.-—. — _ i _ j-L ' . R L

- MINING LANDS -

DATE OF ISSUEI0355fi l (0353B | W3f9T 1038*6 571373 | 37137* 371371~ "~" ~ " (C) MRO '0 MAO Ctr~ H~ ~~103563 t'03562 110356' M03560 l BTI57T t JTI378 , S7I3T6 APR 27 1973217^50, 217031

^- —^ l - — — -L__j___4_--J__ — -l-1 L. ) L. l L. R. ill.

MINISTRY OF NATURAL RESOURCES817038 2170*^43(u wito (y M.BJO

PUN NO

GERMAN TWf? - M.283 ONTARIO

MINISTRY OF NATURAL RESOURCESSURVEYS AND MAPPING BRANCH

42A)0NWe585 2.12*5 DUNDONALD

26+00 N —

24+OON

22+OON

20+OON ——

18 + 00 N ——

16+OON

14 + OON

12+OON

10 + 00 N —

Lot 3

Cone. IV Cone. Ill

Tx. Loop Z

6 + 50N24-f GOE

26 + OOS

O-f 00

V

Lines 0-20E,

ION - 26N8 + 00 N ——

6 + 00 N

4 + 00 N

2+00 N —

Lot 12

B.L. 0+00

— 26 + 00 N

20+OON

0 + OON

— B.L.-0 + OO

N

42AieNWaS85 2.12*5 DUNDONALD 210

Quadrature O

Quadrature '

. In -phase

IO' O In- phase

N —- Reading obscured by 60 cycle noise

Field survey date: November 13-22, December 4, 1972

January 9-10, 1973

Tx. Loop l 4 + OOS

52 + OOS 0+00

54 + 78 E

Lines 0-20E, 0-ION and Lines 24E - 54+78E complete

Figure 2

ASARCO EXPLORATION COMPANY LIMITED

DUNDONALD TOWNSHIP

CONCESSION III, PARTS OF LOTS 182

CLAIM GROUP 'D'

PROFILES OF IN -PHASE AND QUADRATURENTS NO 42 A /,0 E M ' ̂ S URVEY

DRAWN by: H. Ricketts

APPROVED ;

SCALE ! l : 200

DRAWING NO! 084/3

DATE : February, 1973

NORMAN PATERSON 8 ASSOCIATES LIMITED CONSULTING GEOPHYSICISTS, TORONTO, CANADA