42 h08nw0011 (copy)

l l l l l l l

42H08NWe011 2,9997 TWEED 020

INrKKPRbTATlON HEFUHT OF THti ELhUnOMUNbiriC/MAUNEl'lC SUKVhY

flown by Uighan Surveys * l^rocessing Inc.

torGLEN AUDEN KESUUHCfiS UMi'i'fclJ

Blakelock Townshipby

Steve Kilty and Nadia Caira

l

l

lRECEIVED

"; o

l MKHKG LANDS SECTION

l l l l l l M-1UU

l l l l l l l l l l l l l l l l l l l

42H08NW0011 2.9997 TWEED020C

TABLE OF CQNfENfS

PAGE

SUMMARY AND REOCMV1EN3ATIONS. . . . . . . . . . . . . . . . . . . . . . i

INfRCOUCriON. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l

PROJECf IJOCATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

PROPERTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

SURVEY OPERATONS AND PROCEDURES. . . . . . . . . . . . . . . . . . 3Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Survey Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

SBCriON I: SURVEY RESULTS

OONDUCIXDRS IN THE SURVEY AREA. . . . . . . . . . . . . . . . . 1-1

SECTION II:mCKGRQUND INI-OUM4TION. . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-1

ELIO1CMAGNETICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-1Geometric Interpretation..................... 1 1-2Discrete Conductor Analysis.................. 1 1-2X-type Electromagnetic Responses............. 11-10The Thickness Parameter . . . . . . . . . . . . . . . . . . . . . . 1 1-11Resistivity Mapping. . .. . . ....... . . . . .... . ... . 11-12Interpretation in Conductive Environments.... 11-16Reduction of Geologic Noise.................. 11-18EM Magnetite Mapping. . . . . . . . . . . . . . . . . . . . . . . . . 1 1-19Recognition of Culture....................... 11-21

TOfAL FIELD MAGNETICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-24

VLF-EM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-27

MAPS ACCOMPANYING! THIS REPORT

APPENDICESA. The Flight Record and Path Recovery


LISP OF FIGURES

FIGURE l Kegional Location Map 1:250,000 FIGURE 2 Claim Location Map l'^i;2 mile

(Blakelock and Tweed Townships) FIGURE 3 Electromagnetic Anomalies

Sheet l 1:10,000 FIGURE 3a Electromagnetic Anomalies

Sheet 2 1:10,000 FIGURE 4 Total Field Magnetics

Sheet l 1:10,000 FIGURE 4a Total Field Magnetics

Sheet 2 1:10,000 FIGURE 5 Enhanced Magnetics

Sheet l 1:10,000 FIGURE 5a Enhanced Magnetics

Sheet 2 1:10,000 FIGURE 6 Resistivity OOOHz)

Sheet l 1:10,000 FIGURE Ga Resistivity (900Hz)

Sheet 2 1:10,000

l l l

SIM1AKY AN) RKXMVIRNDATIONS

l A total of 800km (500 miles) of survey was flown with the

DIGHEM III system in December 1986, on behalf of several

l exploration companies, over an area near Cochrane, Ontario. Glen

m Auden Resources Limited holds an 87 claim property in Blakelock

Township and an 80 claim block in Tweed and Bragg Townships,

l Ontario all of which were covered by the Dighem Survey.

The survey outlined several discrete bedrock conductors

m associated with areas of low resistivity. Most of these

B anomalies appear to warrant further investigation using

appropriate surface exploration techniques. Areas of interest

l may be assigned priorities for follow-up work on the basis of

supporting geological and/or geochemical information.

The area of interest contains several anomalous features,

l many of which are considered to be of moderate to high priority

as exploration targets.

l

l

l

l

l

l

l

l

l

- l -

l

l

l

l A DIQ11M 1 1 1 electromagnetic/resistivity/magnetic/VLF survey

totalling 152.8 line-km (95.5 line-miles) in Blakelock Township

l and 175 line-km (109.38 line-miles) in Tweed and Bragg Townships

. was flown for Glen Auden Resources Limited 87 and 80 claim

properties in Decanber, 1986, in the Cochrane area of Onario

l (Figure 1).

The properties are located in northwest Blakelock and

l southeast Tweed-north Bragg Townships. This location is on the

m western part of the Burntbush greenstone belt and covers an

extension of a series of iron formations and sediments that trend

l west from a new gold discovery in Casa Berardi Township in

Quebec.

l Potential for stratabound sulphide gold deposits exist on

m the property as well as possibilities for disseminated pyrite

hosted gold deposits within porphyritic and/or felsic volcanic

l tuffs. Previous work southeast of the property in Blakelock

Township gave a 0.03 oz gold assay over 3 feet within a porphyry

containing disseminated sulphides. Other sulphide horizons have

l been indicated by earlier electromagnetic surveys. A new gold

discovery by Newmont Exploration of Canada in Noseworthy

J Township, 10 miles east of the property, has been announced with

0.116 oz Au over 25 feet in a chert horizon. This zone is on the

same iron formation package that extends from Casa Berardi

l l *

Township west of the property,

l PROJECT LOCATION

g The properties are located in northwest Blakelock Township

* and southeast Tweed - northeast Bragg Townships, 48 air miles

8 northeast of Cochrane, Cnario (see Figure 1).

Access to the 80 claim property is via the new Detour Mine

8 road that passes through the northwesstern boundary of the 80

. claim property and passes 9 miles to the northwest of the 87

claim property (see Figure 1). In addition part of the Abitibi

l Paper road system reaches a point 8 mi less to the southeast of

the 80 claim property and 4 miles to the south of the 87 claim

8 property.

M The property can be reached by float plane from Cochrane by

landing on Mikwam Lake and traversing southwest about 4

l kilometers. Helicopter service is also available in Cochrane to

reach the property.

8 The survey objective is the detection and location of base

M metal sulphide conductors as well as any structures and

conductivity patterns which could have a positive influence on

B gold and base metal exploration.

PHOPRKTY

8 The properties consist of an 80 claim block and an 87 claim

B block as shown on the claim map of Blakelock, Tweed, Bragg

Townships at the back of this report (see Figure 2).

l

l

l

11 *11111111111111111

- 3 -

TWEED-BRAGG TOWNSHIPS - 80 CLAIM BLOCK

BRAGG TOWNSHIPClaim Number No. Recording Date

835834-835835 2 December 11, 1985835777 1 December 11, 1985835444 1 December 11, 1985

4

TWEED TOWNSHIPClaim Number No. Recording Date

860978-861037 60 January 15, 1986835773-835776 4 December 11, 1985835830-835833 4 December 11, 1985835836-835843 8 Decaifoer 11, 1985

76

The claims are in the process of being transferred into Glen

Auden Resources Limited name.

BLAKELOCK TOWNSHIP -87 CLAIM BLOCKClaim Number No.

L859831-L859874 44L860300-L860303 4L860312-L860315 4L860321 1L860326-L860354 29L864701-L864702 2L864705-L864706 2L864708 1

87

The claims are in Glen Auden Resources Limited name.

SURVEY OPERATIONS AND PROCEDURES

The flight path recovery was completed at the survey base,

while the final data compilation and drafting was carried out

DIGHEM at its Mississauga, Ontario office. The magnetic

by

and

ll

- 4 -

l

electromagnetic processing was carried out using DIGHEM software

and computer drafting. The INPUf interpretation and report was

completed by Steve Kilty, Chief Geophysicist.

Instruments

l The Astar 350D turbine helicopter (C-GATX) flew at an

average airspeed of lOOkm/hr with an EM bird height of

approximately 30m. Ancillary equipment consisted of a Sonotek

.m PMH5010 magnetometer with its bird at an average height of 45m, a

Sperry radio altimeter, a Geocam sequence camera, an RMS GR 33

l digital graphics recorder, a Sonotek SDS1200 digital data

acquisition system and a Digidata 1140 9-track 800-bpi magnetic

8 tape recorder.

m Survey Procedure

The analog equipment recorded four channels of EM data at

l approximately 900Hz, two channels of EM data at approximately

7200Hz, two channels of EM data at approximately 5600Hz, four

* channels of VLF-EM information (total field and quadrature

l components), two ambient EM noise channels (for the coaxial and

coplanar receivers), two channels of magnetics (coarse and fine

f count), and a channel of radio altitude. The digital equipment

* recorded the above parameters, with the EM data to a sensitivity

* of 0.2ppm at 900IIz, 0.4ppm at 7200Hz, the VLF field to Q.1%, and

l the magnetic field to one nT (i.e., one gamna).

Appendix A provides details on the data channels, their

l

l

l

ll *

respective sensitivities, and the flight path recovery procedure.

m Noise levels of less than 2ppn are generally maintained for wind

m speeds up to SSkm/hr. Higher winds may cause the system to be

grounded because excessive bird swinging produces difficulties in

l flying the helicopter. The swinging results from the 5m of area

which is presented by the bird to broadside gusts.

l EM anomalies shown on the electromagnetic anomaly map are

M based on a near-vertical, half plane model. This model best

reflects "discrete" bedrock conductors. Wide bedrock conductors

l or flat-lying conductive units, whether from surficial or bedrock

sources, may give rise to very braod anomalous responses on the

" EM profiles. These may not appear on the electromagnetic anomaly

B map if they have a regional character rather than a locally

anomalous character. These broad conductors, which more closely

l approximate a half space model, will be maximum coupled to the

horizontal (coplanar) coil-pair and are clearly evident on the

* resistivity map. The resistivity map, therefore, may be more

l valuable than the electromagnetic anomaly map, in areas where

broad or flat-lying coductors are considered to be of importance,

l Some of the weaker anomalies could be due to aerodynamic

m noise, i.e., bird bending, created by abnormal stresses to which

the bird is subjected during the climb and turn of the aircraft

l between lines. Such aerodynamic noise is usually manifested by

an anomaly on the coaxial inphase channel only, although severe

l

l

- 6 -l l

stresses can affect the coplanar inphase channels as well.

m In areas where EM responses are evident only on the

m quadrature components, zones of poor conductivity are indicated.

Where these responses are coincident with strong magnetic

l anomalies, it is possible that the inphase component amplitudes

have been suppressed by the effects of magnetite. Most of these

B poorly-conductive magnetic features give rise to resistivity

fl anomalies which are only slightly below background. These weak

features are evident on the resistivity map but may not be shown

l on the electromagnetic anomaly map. If it is expected that

poorly-conductive sulphides may be associated with magnetite-rich

units, sane of these weakly anomalous features may be of

B interest. In areas where magnetite causes the inphase components

l

l

l

i i i i

to become negative, the apparent conductance and depth of EM

anomlies may be unreliable.

CONDUCTORS IN THE SURVEY AREA

l l *

SBCTIQN I: SURVEY RESULTS

lThe main survey covered two grids with 800km of flying

'l covering several different exploration companies property. Glen

Auden Resources Limited holds an 87 claim property, the results

B of which are shown on the map sheets at the back of this report

l (see Figures 3a,4a,5a)

The electromagnetic anomaly map shows the anomaly locations

l with the interpreted conductor type, dip, conductance and depth

being indicated by symbols. Direct magnetic correlation is also

shown if it exists. The strike direction and length of the

B conductors are indicated when anomalies can be correlated from

line to line. When studying the map sheets for follow-up

l planning, consult the anomaly listings appended to this report to

. ensure that none of the conductors are overlooked.

The resistivity map shows the conductive properties of the

l survey area. Sane of the resistivity lows (i.e., conductive

areas) coincide with discrete bedrock conductors and others

l indicate conductive overburden or broad conductive rock units.

m The resistivity patterns may aid geologic mapping and in

extending the length of known zones.

lThe 87 claim block of Glen Auden Resources Limited covered

l

l

l l

by the DIGllfcM survey is dominated by a highly magnetic feature

l that strikes west-southwest in the north-central portion of the

m claim group, and appears to indicate a faulted section of a

possible iron formation.

l A moderately strong bedrock conductor of moderate

conductivity thickness is coincident with the magnetic anomaly.

m The conductor trends west-southwest for l kilometer. Another

m fairly strong magnetic high is located in the southern half of

the claim group and extends southwest from the northeastern

l corner of the claim block. The magnetic high trends west along

the top of Floodwood Lake.

B Another isolated strong magnetic high is located between the

H two anomalies mentioned previously located approximately l

kilometer north of the most eastern bay of Floodwood Lake (line

J 20220). This response may indicate a faulted section of a nearby

iron formation.

. Anomalies 20210-20240

l These moderate bedrock conductors are striking

west-southwest and are associated with a prominent magnetic high

l typical of an iron formation. These anomalies probably reflect

lthe presence of pyrrhotite within an iron formation.

Anomalies 20140-20170

l These moderate bedrock conductors are located along the edge

of a linear west-southwest striking magnetic anomaly. The

l

l

l

l l

conductor is not associated directly with the magnetic high and

l may be reflecting mineralization along a contact.

m Anomaly 2U190

This weaker anomaly appears to reflect an isolated weakly

l magnetic conductor. This zone could reflect possible sulfides

and should be investigated on the ground.

ln The 80 claim block of Glen Auden Resources Limited covered

by the DIQIEVI survey is dominated by a highly magnetic feature

l that strikes northeast from the NE corner to west throughout the

rest of the claim group. A moderately strong conductor is

l located along the southern boundary of the magnetic anomaly. The

m conductor is not associated directly with the magnetic high and

may be reflecting mineralization along a contact. This zone may

l be due to graphite.

Another strong isolated magnetic high is located along the

m eastern boundary of the claim block. The magnetic high trends

B east-west and appears to be part of a faulted section of the main

iron formation. A strong conductor is located associated with

l this prominent magnetic high typical of an iron formalion. These

anomalies probably reflect the presence of pyrrhotite within an

" iron formation.

l Another tightly folded magnetic high is located in the

southeastern claim corner. A strong conductor is located

l

l

l

ll

directly associated with this folded magnetic high typical of a

P folded iron formation. These anomalies probably reflect the

presence of pyrrhotite within an iron formation.

Finally an isolated magnetic high is located in the western

l portion of the claim block. A few strong conductors are

associated directly with this high and appear to be part of a

l faulted section of the main iron formation mentioned previously.

M This magnetic high is flanked on either side by weaker,

intermittent conductors. The central conductor most likely

l reflects a conductive iron formation with the weaker conductors

indicating mineralization along the contacts.

l A cluster of moderate bedrock conductors is located along

m the northern boundary of the claim block just north of claim

861008. This conductor is predominantly non-magnetic.

l

l

l

l

l

l

l

l

l

l l l l

SECTION II: BACKGROUND INFORMATION

ELECTROMAGNETICS

l DIGHI3M electromagnetic responses fall into two general

classes, discrete and broad. The discrete class consists of

l sharp, well-defined anomalies from discrete conductors such

m as sulfide lenses and steeply dipping sheets of graphite and

sulfides. The broad class consists of wide anomalies from

l conductors having a large horizontal surface such as flatly

dipping graphite or sulfide sheets, saline water-saturated

" sedimentary formations, conductive overburden and rock, and

l geothermal zones. A vertical conductive slab with a width

of 200 m would straddle these two classes.

lm . The vertical sheet (half plane) is the most common

model used for the analysis of discrete conductors. All

l anomalies plotted on the electromagnetic map are analyzed

m according to this model. The following section entitled

Discrete Conductor Analysis describes this model in detail,

l including the effect of using it on anomalies caused by

broad conductors such as conductive overburden.

l The conductive earth (half space) model is suitable for

broad conductors. Resistivity contour maps result from the

l

l

l - II-2 -

l * use of this model. A later section entitled Resistivitylm Mapping describes the method further, including the effect

l of using it on anomalies caused by discrete conductors such

as sulfide bodies.

l\

m Geom e tr i c in t e rpre t a tion

l - ' The geophysical interpreter attempts to determine the

geometric shape and dip of the conductor. Figure II-1 shows

l typical DIG11EM anomaly shapes which are used to guide the

m geometric interpretation.

l Discrete conductor analysis

* The EM anomalies appearing on the electromagnetic map

l ' are analyzed by computer to give the conductance (i.e.,

conductivity-thickness product) in mhos of a vertical sheet

model. This is done regardless of the interpreted geometric

l shape of the conductor. This is not an unreasonable

procedure, because the computed conductance increases as the

l electrical quality of the conductor increases, regardless of

. its true shape. DIGHEM anomalies are divided into six

grades of conductance, as shown in Table I1-1. The conduc-

I tance in mhos is the reciprocal of resistance in ohms.

l

l

Conductor

location

Channel CXI

Channel CPI

Channel DIFI

II l li i

A

J

\

\

Interpretive ^ D E D Tsymbol

r s \ rConductor: -* | \ L,

T C

\\ 0D : vertical dipping vertical dipping sphere;

\- thin dike thin dike thick dike thick dike horizontal

E s probableconductor beside astronger one

Ratio of

amplitudes

disk;

metal roof;

email fenced

yard

CXI/CPI : 4 2 variable variable variable '/4

R S, H, G E p

b*S'Vt'N**A'VS^B^NxV*'*~**^N^'S^

wide S - conductive overburden Flight line

horizontal H 5 thick conductive cover parallel to.. . or near-surface wide ^ .

rlbbon i conductive rock unit conductorlarge fenced G B wide conductiye rc;k

orea unit buried underresistive cover

. E- edge effect from wideconductor

variable 1/2 ^'/4

Figure TT -i Typical DIGHEM anomaly shapes

1111111111111111111

- II-4 -

ftTable I 1-1. EM Anomaly Grades

Anomaly Grade Mho Range

6 > 995 50-994 20-493 10-192 5-9'1. < 5

i

*

.

-

The conductance value is a geological parameter because

it is a characteristic of the conductor alone. I.t

is independent of frequency, and of flying height

generally

or depth

of burial apart from the averaging over a greater portion of

the conductor as height increases. 1 Small anomalies from

deeply buried strong conductors are not confused with small

anomalies from shallow weak conductors because the former

will have larger conductance values.

Conductive overburden generally produces

responses which are not plotted on the EM maps.

broad EM

However,

patchy conductive overburden in otherwise resistive areas

1 This statement is an approximation. DIGI1EM, with itsshort coil separation, tends to yield larger and more accurate conductance values than airborne systemshaving a larger coil separation.

l - 11-5 -

l

m

l ^rcan yield discrete anomalies with a conductance grade (cf .

Table II-1) of 1, or even of 2 for conducting clays whichl* have resistivities as low as 50 ohm-in. In areas where

H ground resistivities can be below 10 ohm-m, anomalies caused

by weathering variations and similar causes can have any

J conductance grade. The anomaly shapes from the multiple

^ coils often allow such conductors to be recognized, and

these are indicated by the letters S, H, G and sometimes E

l on the map (see EM legend).

For bedrock conductors, the higher anomaly grades

indicate increasingly higher conductances. Examples:

DIGHEM's New Insco copper discovery (Noranda, Canada)

l yielded a grade 4 anomaly, as did the neighbouring

copper-zinc Magusi River ore body; Mattabi {copper-zinc,

" Sturgeon Lake, Canada) and Whistle (nickel, Sudbury,

l ' Canada) gave grade 5; and DIGHEM's Montcalm nickel-copper

discovery (Timmins, Canada) yielded a grade 6 anomaly.

B Graphite and sulfides can span all grades but, in any

l particular survey area, field work may show that the

different grades indicate different types of conductors.

lm Strong conductors (i.e., grades 5 and 6) are character-

istic of massive sulfides or graphite. Moderate conductors

l (grades 3 and 4) typically reflect sulfides of. a less

massive character or graphite, while weak bedrock conductors

l


- II-6 -

(grades 1 and 2) can signify poorly connected graphite or

heavily disseminated sulfides. Grade 1 conductors may not

respond to ground EM equipment using frequencies less than

2000 Hz.

The presence of sphalerite or gangue can result in

ore deposits having weak to moderate conductances. As

an example, the three million ton lead-zinc deposit of

llestigouche Mining Corporation near Bathurst, Canada,

yielded a well defined grade 1 conductor. The 10 percent

by volume of sphalerite occurs as a coating around the fine

grained massive pyrite, thereby inhibiting electrical

conduction.

Faults, fractures and shear zones may produce anomalies

which typically have low conductances (e.g., grades 1

and 2). Conductive rock formations can yield anomalies of

any conductance grade. The conductive materials in such

rock 'formations can be salt water, weathered products such

as clays, original depositional clays, and carbonaceous

material.

On the electromagnetic map, a letter identifier and an

interpretive symbol are plotted beside the EM grade symbol.

The horizontal rows of dots, under the interpretive symbol,

indicate the anomaly amplitude on the flight record. The

l - II-7 -

vertical column of dots, under the anomaly letter, gives the

estimated depth. In areas where anomalies are crowded, the

8 letter identifiers, interpretive symbols and dots may be

m obliterated. The EM grade symbols, however, will always be

discernible, and the obliterated information can be-obtained

l from the anomaly listing appended to this report.

" Tlie purpose of indicating the anomaly amplitude by dots

B is to provide an estimate of the reliability of the conduc

tance calculation. Thus, a conductance value obtained from

l a1 large ppm anomaly (3 or 4 dots) will tend to be accurate

M whereas one obtained from a small ppm anomaly (no dots)

could be quite inaccurate. The absence of amplitude dots

l indicates that the anomaly from the coaxial coil-pair is

5 ppm or less on both the inphase and quadrature channels.

8 Such small anomalies could reflect a weak conductor at the

l ' surface or a stronger conductor at depth. The conductance

grade and depth estimate -illustrates which of these

l possibilities fits the recorded data best.

Flight line deviations occasionally yield cases where

l two anomalies, having similar conductance values but

B dramatically different depth estimates, occur close together

on the same conductor. Such examples illustrate the

l reliability of the conductance measurement while showing

that the depth estimate can be unreliable. There are a

l

- II-O -

number of factors which can produce an error in the depth

estimate, including the averaging of topographic variationst

by the altimeter, overlying conductive overburden, and the

location and attitude of the conductor relative to the

flight line. Conductor location and attitude can provide an

erroneous depth estimate because the stronger part of the

conductor may be. deeper or to one side of the flight line,

or because it has a shallow dip. A heavy tree cover can

also produce errors in depth estimates. This is because the

depth estimate is computed as the distance of bird from

g conductor, minus the altimeter reading. The altimeter can

lock onto the top of a dense forest canopy. This situation

yields an erroneously large depth estimate but does not

l affect the conductance estimate.

B Dip symbols are used to indicate the direction of dip

l of conductors. These symbols are used only when the anomaly

shapes are unambiguous, which usually requires a fairly

l resistive environment.

A further interpretation is presented on the EH map by

l means of the line-to-line correlation of anomalies, which is

based on a comparison of anomaly shapes on adjacent lines.

This provides conductor axes which may define the geological

l structure over portions of the survey area. The absence of

l

l

- II-9 -

axes in an area implies that anomalies could not

be correlated from line to line with reasonable confidence.

DIGHEM electromagnetic maps are designed to provide

a correct impression of conductor quality by means of the

conductance grade symbols. The symbols can stand alone

with geology when planning a follow-up program. The actual

conductance values are printed in the attached anomaly list

for those who wish quantitative data. The anomaly ppm and

depth are indicated by inconspicuous dots which should not

J distract from the conductor patterns, while being helpful

to those who wish this information. The map provides an

interpretation of conductors in terms of length, strike and

l dip, geometric shape, conductance, depth, and thickness (see

below) . ' The accuracy is comparable to an interpretation

m from a high quality ground EM survey having the same line

l ' spacing.

l The attached EM anomaly list provides a tabulation of

m anomalies in ppm, conductance, and depth for the -vertical

sheet model. The EM anomaly list also shows the conductance

l and depth for a thin horizontal sheet (whole plane) model,

but only the vertical sheet parameters appear on the

" EM map. The horizontal sheet model is suitable for a flatly

l dipping thin bedrock conductor such as a sulfide sheet

having a thickness less than 10 in. The list also shows the

l

l

l

l l l l l l l l l l l l l l l l l l

- 11-10 -

^resistivity and depth for a conductive earth (half space)

model, which is suitable for thicker slabs such as thickt

conductive overburden. In the EM anomaly list, a depth

value of zero for the conductive earth model, in an area of

thick cover, warns that the anomaly may be caused by

conductive overburden.

Since discrete bodies normally are the targets of

EM surveys, local base (or zero) levels are used to compute

local anomaly amplitudes. This contrasts with the use

of true zero levels which are used to compute true EM

amplitudes. Local anomaly amplitudes are shown in the

EM anomaly list and these are used to compute the vertical

sheet parameters of conductance and depth. Not shown in the

EM anomaly list are the true amplitudes which are used to

compute the horizontal sheet and conductive earth

parameters,

X-typo electromagnetic responses

DIGI1EM maps contain x-type EM responses in addition

to EM anomalies. An x-type response is below the noise

threshold of 3 ppm, and reflects one of the following: a

weak conductor near the surface, a strong conductor at depth

(e.g., 100 to 120 m below surface) or to one side of the

flight line, or aerodynamic noise. Those responses that

- 11-11 -

)have the appearance of valid bedrock anomalies on the flight

profiles are indicated by appropriate interpretive symbols

{see EM map legend). The others probably do not warrant

further investigation unless their locations are of

considerable geological interest.

The thickness parameter

DIGI1EM can provide an indication of the thickness of

a steeply dipping conductor. The amplitude of the coplanar

anomaly (e.g., CPI channel on the digital profile) increases

relative to the coaxial anomaly (e.g./ CXI) as the apparent

thickness increases, i.e., the thickness in the horizontal

plane. (The thickness is equal to the conductor width if

the conductor dips at 90 degrees and strikes at right angles

to the flight line.) This report refers to a conductor as

l ' thin .when the thickness is likely to be less than .3 m, and

thick when in excess of 10 m. Thick conductors are

l indicated on the EM map by crescents. For base metal

m exploration in steeply dipping geology, thick conductors can

be high priority targets because many massive sulfide ore

l bodies are thick, whereas non-economic bedrock conductors

are often thin. The system cannot sense the thickness when

the strike of the conductor is subparallel to the flight

l line, when the conductor has a shallow dip, when the anomaly

l

l

- 11-12 -

amplitudes are small, or when the resistivity of the

environment is below 100 ohm-m.i

Resistivity mapping

Areas of widespread conductivity are commonly

encountered during surveys. In such areas, anomalies can

be generated by decreases of only 5 m in survey altitude as

well as by increases in conductivity. The typical flight

record in conductive areas is characterized by inphase and

quadrature channels which are continuously active. Local

EM peaks reflect either increases in conductivity of the

earth or decreases in survey altitude. For such conductive

areas, apparent resistivity profiles and contour maps are

necessary for the correct interpretation of the airborne

l data. The advantage of the resistivity parameter is

l ' that anomalies caused by altitude changes are virtually

eliminated, so the resistivity data reflect only those

l anomalies caused by conductivity changes. The resistivity

m analysis also helps the interpreter to differentiate between

conductive trends in the bedrock and those patterns typical

l of conductive overburden. For example, discrete conductors

will generally appear as narrow lows on the contour map

" and broad conductors (e.g., overburden) will appear as

B wide lows.

l

l


- 11-13 -

The resistivity profile (see table in Appendix A) and

the resistivity contour map present the apparent resistivity

using the co-culled pseudo-layer (or buried) half space

model defined in Fraser (1970) 2 . This model consists of

a resistive layer overlying a conductive half space. The

depth channel (see Appendix A) gives the apparent depth

below surface of the conductive material. The apparent

depth is simply the apparent thickness of the overlying

resistive layer. The apparent depth (or thickness)

parameter will be positive when the upper layer is more

resistive than the underlying material, in which case the

apparent depth may be quite close to the true depth.

The apparent depth will be negative when the upper

layer is more conductive than the underlying material, and

will be zero when a homogeneous half space exists. The

apparent, depth parameter must be interpreted cautiously

because it will contain any errors which may exist in the

measured altitude of the EM bird {e.g., as caused by a dense

tree cover). The inputs to the resistivity algorithm are

the inphase and quadrature components of the coplanar

coil-pair. The outputs are the apparent resistivity of the

Resistivity mapping with an airborne multicoil electro magnetic system: Geophysics, v. 43, p. 144-172.

- 11-14 -

^conductive half space (the source) and the sensor-source

distance. The flying height is not an input variable,

and the output resistivity and sensor-source distance are

independent of the flying height. The apparent depth,

discussed above, is simply the sensor-source distance minus

the measured altitude or flying height. Consequently,

errors in the measured altitude will affect the apparent

depth parameter but not the apparent resistivity parameter.

The apparent depth parameter is a useful indicator

J of simple layering in areas lacking a heavy tree cover.

g The DIGHEM system has been flown for purposes of permafrost

mapping, where positive apparent depths were used as a

l measure of permafrost thickness. However, little quantita

tive use has been made of negative apparent depths because

" the absolute value of the negative depth is not a measure of

fl ' the thickness of the conductive upper layer and, therefore,

is not meaningful physically. Qualitatively, a negative

l apparent depth estimate usually shows that the EM anomaly is

m caused by conductive overburden. Consequently, the apparent

depth channel can be of significant help in distinguishing

l between,overburden and bedrock conductors.

" The resistivity map often yields more useful informa-

I tion on conductivity distributions than the EM map. In

l

l

- 11-15 -

comparing the EM and resistivity maps, keep in mind the

following:

(a) The resistivity map portrays the absolute value

of the earth's resistivity.

{Resistivity ^ 1/conductivity.)

(b) 'The EM map portrays anomalies in the earth's

resistivity. An anomaly by definition is a

change from the norm and so the EM map displays

l anomalies, (i) over narrow, conductive bodies and

M (ii) over the boundary zone between two wide

formations of differing conductivity.

lThe resistivity map might be likened to a total

" field map and the EM map to a horizontal gradient in the

l ' direction of flight3 . Because gradient maps are usually

more sensitive than total field maps, the EM map therefore

l is to be preferred in resistive areas. However, in conduc-

m tive areas, the absolute character of the resistivity map

usually causes it to be more useful than the EM map.

l

3 The gradient analogy is only valid with regard to l the identification of anomalous locations.

l

l

- 11-16 -

Interpretation in conductive pnvirpniiioiiLs

, 4

Environments having background resistivities below

30 ohm-m cause all airborne EM systems to yield very

large responses from the conductive ground. This- usually

prohibits the recognition of discrete bedrock conductors.

The processing .of DIGHEM data, however, produces six

channels which contribute significantly to the recognition

of bedrock conductors. These are the inphase and quadrature

difference channels (DIPI and DIFQ), and the resistivity and

depth channels (RES and DP) for each coplanar frequency; see

table in Appendix A.

l . The EH difference channels (DIFI and DIFQ) eliminate

up to 99S of the response of conductive ground, leaving

8 responses from bedrock conductors, cultural features (e.g.,

m ' telephone lines, fences, etc.) and edge effects. An edge

effect arises when the conductivity of the ground suddenly

l changes, and this is a source of geologic noise. While edge

g effects yield anomalies on the EM difference channels, they

do not produce resistivity anomalies. Consequently, the

l resistivity channel aids in eliminating anomalies due to

edge effects. On the other hand, resistivity anomalies

" will coincide with the most highly conductive sections of

B conductive ground, and this is another source of geologic

l

l


- 11-17 -

noise. - The recognition of a bedrock conductor in at

conductive environment therefore is based on the anomalous

responses of the two difference channels {DIFI and DXFQ)

and the two resistivity channels (RES). The most favourable

situation is where anomalies coincide on all four channels.

The DP channels, which give the apparent depth to the

conductive material, also help to determine whether a

conductive response arises from surficial material or from a

conductive zone in the bedrock. When these channels ride

above the zero level on the digital profiles (i.e., depth is

negative), it implies that the EM and resistivity profiles

are responding primarily to a conductive upper layer, i.e.,

conductive overburden. If both DP channels are below the

zero level, it indicates that a resistive upper layer

exists, and this usually implies the existence of a bedrock

conductor. If the low frequency DP channel is below the

zero level and the high frequency DP is above, this suggests

that a bedrock conductor.occurs beneatli conductive cover.

The conductance channel CDT identifies discrete

conductors which have been selected by computer for

appraisal by the geophysicist. Some of these automatically

- 11-10 -

selected anomalies on channel CDT are discarded by the

geophysicist. The automatic selection algorithm is4

intentionally oversensitive to assure that no meaningful

responses are missed. The interpreter then classifies the

anomalies according to their source and eliminates those

that are not substantiated by the data, such as those

arising from geologic or aerodynamic noise.

Reduction of geologic noise

Geologic noise refers to unwanted geophysical

responses. For purposes of airborne EM surveying, geologic

noise refers to EM responses caused by conductive overburden

and magnetic permeability. It was mentioned above that

.the EM difference channels (i.e., channel DIPI for inphase

and DIFQ for quadrature) tend to eliminate the response of

conductive overburden. This marked a unique development

in airborne EM technology, as DIGIIEM is the only EM system

which yields channels having an exceptionally high degree

of immunity to conductive overburden.

Magnetite produces a form of geological noise on the

inphase channels of all EM systems. Hocks containing less

than ' U magnetite can yield negative inphase anomalies

caused by magnetic permeability. When magnetite is widely

- 11-19 -

distributed throucjliout a survey area, the inphase EM chan

nels may continuously rise and fall reflecting variationst

in the magnetite percentage, flying height, and overburden

thickness. This can lead to difficulties in recognizing

deeply buried bedrock conductors, particularly if conductive

overburden also exists. However, the response of broadly

distributed magnetite generally vanishes on the inphase

difference channel DIFI. This feature can be a significant

aid in the recognition of conductors which occur in rocks

containing accessory magnetite.

EM m ag n e t i t e m app ing

The information content of DIGHEM data consists of a

combination of conductive eddy current response and magnetic

permeability response. The secondary field resulting from

conductive eddy current flow is frequency-dependent and

consists of both inphase and quadrature components, which

are positive in sign. On the other hand, the secondary

field resulting from magnetic permeability is independent

of frequency and consists of only an inphase component which

is negative in sign. When magnetic permeability manifests

itself by decreasing the measured amount of positive

inphase, its presence may be difficult to recognize.

However, when it manifests itself by yielding a negative

~ 11-20 -

inphase anomaly (e.g., in the absence of'eddy current flow),

its presence is assured. In this latter case, the negative

component can be .used to estimate the percent magnetite

content.

A magnetite mapping technique was developed for the

coplanar coil-pair of DIGHEM. The technique yields channel

"FED", (see Appendix A) which displays apparent weighti

percent magnetite according to a homogeneous half space

model.4 The method can be complementary to magnetometer

mapping in certain cases. Compared to magnetometry, it is

far less sensitive but is more able to resolve closely

spaced magnetite zones, as 'well as providing an estimate

of the amount of magnetite in the rock. The method is

sensitive to T/4% magnetite by weight when the EM sensor is

at a height of 30 m above a magnetitic half space. It can

individually resolve steeply dipping narrow magnetite-rich

bands which are separated by 60 m. Unlike magnetometry, the

EM magnetite method is. unaffected by remanent magnetism or

magnetic latitude.

The EM magnetite mapping technique provides estimates

of magnetite content which are usually correct within a

Refer to Fraser, 1901, Magnetite mapping with a multicoil airborne electromagnetic system: Geophysics, v. 46, p. 1579-1594.

- 11-21 -

factor of 2 when the magnetite is fairly uniformly

distributed. EM magnetite maps can be generated when

magnetic permeability is evident as indicated by anomalies

in the magnetite channel FED.

Like magnetometry, the EM magnetite method maps

only bedrock fe.atures, provided that the overburden is

characterized by a general lack of magnetite. This

contrasts with resistivity mapping which portrays the

combined effect of bedrock and overburden.

Recognition of culture

Cultural responses include all EM anomalies caused by

man-made metallic objects. Such anomalies may be -caused by

inductive coupling or current gathering. The concern of the

interpreter is to recognize when an EM response is due to

culture. Points of consideration used by the interpreter,

when coaxial and coplanar coil-pairs are operated at a

common frequency, are as follows:

1. Channels CXS and CPS (see Appendix A) measure 50 and

60 Hz radiation. An anomaly on these channels shows

that the conductor is radiating cultural power. Such

an indication is normally a guarantee that the conduc-

l

. - 11-22 -

l tor is cultural. However, care must be taken to ensure

that the conductor is not a geologic body which strikesl across a power line, carrying leakage currents.

l2. A flight which crosses a "line" (e.g., fence, telephone

l line, etc.) yields a center-peaked coaxial anomaly

. and an in-shaped coplanar anomaly, 5 When the flight

crosses the cultural line at a high angle of inter-

I section, the amplitude ratio of coaxial/coplanar

(e.g., CXI/CPI) is 4. Such an EM anomaly can only be

8 caused by a line. The geologic body which yields

m anomalies most closely resembling a line is the

vertically dipping thin dike. Such a body, however,

J yields an amplitude ratio of 2 rather than 4.

Consequently, an in-shaped coplanar anomaly with a

CXI/CPI amplitude ratio of 4 is virtually a guarantee

l ' that the source is a cultural line,

" 3. A flight which crosses a sphere or horizontal disk

l , yields center-peaked coaxial and coplanar anomalies

with a CXI/CPI amplitude ratio (i.e., coaxial/coplanar)

l ' of. 1/4. In the absence of geologic bodies of this

m geometry, the most likely conductor is a metal roof or

l 5 See Figure II-1 presented earlier,

l

l


5.

- 11-23 -

small fenced yard. 6 Anomalies of this type are

virtually certain to be cultural if they occur in an

area of culture.

A flight which crosses a horizontal rectangular body or

wide ribbon yields an in-shaped coaxial anomaly and a

center-peaked coplanar anomaly. In the absence of

geologic bodies of this geometry, the most likely

conductor is a large fenced area. 6 Anomalies of this

type are virtually certain to be cultural if they occur

in an area of culture*

EM anomalies which coincide with culture, as seen on

the camera film, are usually caused by culture.

However, care is taken with such coincidences because

a geologic conductor could occur beneath a fence, for

example. In this example, the fence would be expected

to yield an m-shaped coplanar anomaly as in case j}2

above. If, instead, a center-peaked coplanar anomaly

occurred, there would be concern that a thick geologic

conductor coincided with the cultural line.

6 It is a characteristic of EM that geometrically identical anomalies are obtained from: (1) a planar conductor, and (2) a wire which forms a loop having dimensions identical to the perimeter of the equiva lent planar conductor.

l - 11-24 -

6 * '^ Q above description of anomaly shapes is valid

when the culture is not conductively coupled to the

l environment. . In this case, the anomalies arise from

m inductive coupling to the EM transmitter. However,

when, the environment is quite conductive (e.g., less

l than 100 ohm-m at 900 Hz), the cultural conductor may

be conductively coupled to the environment. In this

B latter case, the anomaly shapes tend to be governed by

B current gathering. Current gathering can completely

distort the anomaly shapes, thereby complicating the

l identification of cultural anomalies. In such circum-

B stances, the interpreter can only rely on the radiation

channels CXS and CPS, and on the camera film.

ll TOTAL FIELD MAGNETICS

l The existence of a magnetic correlation with an EM

B anomaly is indicated directly on the EM map. An EM anomaly

with magnetic correlation has a greater likelihood of

g being produced by sulfides than one that is non-magnetic,

m However, sulfide ore bodies may be non-magnetic (e.g., the

1 Kidd Creek deposit near Timmins, Canada) as well as magnetic

l (e.g./ the Mattabi deposit near Sturgeon Lake, Canada).

l

l

l


- 11-25 ~

The magnetometer daLa are digitally recorded in

the aircraft to an accuracy of one nT (i.e., one gamma).

The digital tape . is processed by computer to yield a

total field magnetic contour map. When warranted, the

magnetic data also may be treated mathematically to-enhance

the magnetic response of the near-surface geology, and an

enhanced magnetic contour map is then produced. The

response of the enhancement operator in the frequency domain

is illustrated in Figure II-2. This figure shows that the

passband components of the airborne data are amplified

20 times by the enhancement operator. This means, for

example, that a 100 nT anomaly on the enhanced map reflects

a 5 nT anomaly for the passband components of the airborne

data.

The enhanced map, which bears a resemblance to a

downward continuation map, is produced by the digital

bandpass filtering of the total field data. The enhancement

is equivalent to continuing the field downward to a level

(above the source) which is 1720th of the actual sensor-

source distance.

i

Because the enhanced magnetic map bears a resemblance

to a ground magnetic map, it simplifies the recognition

of trends in the rock strata and the interpretation of

- 1I-2G -

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1 . CYCLES/METRE

1Figure E"2 Frequency response of magnetic enhancement

J operator.

1

1

l - - 11-27 -

g geological structure. It defines the near-surface local

geology while de-emphasizing deep-seated regional features.

It primarily lias application when the magnetic rock units

l are steeply dipping and the earth's field dips in excess

of GO degrees.

ll ' VLF-EM

l1 " - VLF-EM anomalies are not- EM anomalies in the

l conventional sense. EM anomalies primarily reflect eddy

currents flowing in conductors which have been energized

l inductively by the primary field. In contrast, VLF-EM

m anomalies primarily reflect current gathering, which is a

non-inductive phenomenon. The primary field sets up

l currents which flow weakly in rock and overburden, and these

B tend to collect in low resistivity zones* Such zones may be

* due to massive sulfides, shears, river valleys and even

l unconformities.

" - The Herz Industries Ltd Totem VLF-electromagnetometer

M measures the total field and vertical quadrature

components. Both these components are digitally recorded in

l the aircraft with a sensitivity of 0.1 percent. The total

m field yields peaks over VLF-EM current concentrations

l

l

- II-2U -

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lo-1

1 CYCLES X METRE

1Figure H- 3 Froquoncy response of VLF- EM operator.

1

1

1

l- 11-29 -

P whereas the quadrature component tends to yield crossovers.

. 'Doth appear as traces on the profile records. The total

field data also are filtered digitally and displayed on a

l contour map, to facilitate the recognition of trends in the

rock strata and the interpretation of geologic structure.

m The response of the VLF-EM total field filter operator

in the frequency domain (Figure II-3) is basically similar

J to that used to produce the enhanced magnetic map

- (Figure II-2). The two filters are identical along the

abscissa but different along the ordinant. The VLF-EM

l filter removes long wavelengths such as those which reflect

regional and wave transmission variations. The filter

B sharpens short wavelength responses such as those which

l reflect local geological variations. The filtered total

field VLF-EM contour map is produced with a contour interval

l of one percent.

l

• Respectfully submitted, DIGHEM SURVEYS S PROCESSING INC.

l '^-'Km s. J.//Kilty

Chie'r Geophysicisll li /f

l AB-SK-4 6 O

l— APPENDIX A

l THE FLIGUT RECORDS

l Both analog and digital flight records were produced.

m The analog profiles were recorded on chart paper in the

aircraft during the survey. The digital profiles were

l generated later by computer and plotted on electrostatic

chart paper at a scale of 1:15,000. The analog and digital

m profiles are listed in Tables A-1 and A-2 respectively.

lIn Table A-2, the log resistivity scale of 0.06

l decade/mm means that the resistivity changes by an order

g of magnitude in 16.5 mm. The resistivities at O, 33 and

67 mm up from the bottom of the digital flight record are

l respectively 1, 100 and 10,000 ohm-m.

ll NAVIGATION EQUIPMENT

l Aircraft positioning and post-survey recovery of

m aircraft position was accomplished through the use of a Del

Norte positioning system. This electronic navigation system

l

l

operates in the 8 gHz band and is therefore range limited by

hills and by the curvature of the earth.


- A-2 -

Table A-1. The Analog Profiles

Channel Number

CXICXQCPUCPQ1CPI2CPQ2CXSCPSALTMAGCMAG FVLFTVLFQ

Parameter

coaxial inphase ( 900 Hz)coaxial quad { 900 Hz)coplanar inphase ( 900 Hz)coplanar quad ( 900 Hz)coplanar inphase (7200 Hz)coplanar quad (7200 Hz)coplanar inphase(56000 Hz)coplanar quad (56000 Hz)altimetermagnetics, coarsemagnetics, fineVLF-total: AnnapolisVLF-quad: Annapolis

Sensitivity per nun

2.5 ppm2 . 5 ppm2.5 ppm2.5 ppm5 . 0 ppm5.0 ppm

13.0 ppm13.0 ppm3 m10 nT2 nT

2%2%

Designation on computer profile

CXI ( 900 Hz)CXQ ( 900 Hz)

' CPI ( 900 Hz)CPQ { 900 IIz)CPI (7200 Hz)CPQ (7200 Hz)

ALTMAG

Table A-2. The Digital Profiles

ChannelName (Freq)

MAGALTCXI ( 900 Hz)CXQ ( 900 Hz)CPI ( 900 Hz)CPQ ( 900 Hz)CPI (7200 Hz)CPQ (7200 Hz)

DIFI ( 900 Hz)DIFQ ( 900 Hz)SIGTRES ( 900 Hz)RES {7200 Hz)DP ( 900 Hz)DP (7200 Hz)

Observed parameters

magneticsbird heightvertical coaxial coil-pair inphasevertical coaxial coil-pair quadraturehorizontal coplanar coil-pair inphasehorizontal coplanar coil-pair quadraturehorizontal coplanar coil-pair inphasehorizontal coplanar coil-pair quadrature

Computed Parameters

difference function inphase from CXI and CPIdifference function quadrature from CXQ and CPQconductancelog resistivitylog resistivityapparent depthapparent depth

Scaleunits/mm

20 nT6 m2 ppm2 ppm2 ppm2 ppm2 ppm2 ppm

2 ppm2 ppm1 grade.06 decade.06 decade6 m6 m

AB-SK-460

* - A-3 -

l The Del Norte uses two ground based transponder

m stations continuously interrogated by the helicopter mounted

unit and which transmit distance information back to the

J helicopter. The onboard Central Processing Unit then takes

* the two distances and determines the helicopter position

" relative to the two ground stations. This is accomplished

l once every second. The ground stations were set up well

away from the survey area and were positioned such that the

l signals ' crossed the survey blocks at an angle between 30 0

m and 150 8 . After site selection, the aircraft then flew a

baseline at right angles to a line drawn through the

l transmitter sites. The minimum distance recorded when

flying this baseline established the arbitrary coordinate

* system used to fly the survey area. The final step was to

l establish the location of the first flight line on the map

or photomosaic. This line was then flown while pressing a

l "start of line" and "end of line" switch, thereby

B establishing both survey boundaries and line direction. The

distance from each ground transmitter site (range-range) was

l continuously recorded digitally.

The range-range data was transposed during data

l processing into an arbitrary x-y coordinate system based on

the location of the two transmitter sites. This x-y grid

B data was then transferred to the base map by correlating a

H number of prominent topographical features to the

l

l l l

- A-4 -

navigational data points. The use of numerous visual tie-in

points served two purposes: to correct for distortions in

the photomosaic (if any) and to accurately relate the

l navigational data to the map sheet.

l l l l l l l l l l l l l l l

AB-SK-460

© Ministry of Northern Development and Mines

Ontario

Report of Work ^ c(Geophysical, Geological, Geochemical and Expenditures)

Mini42H88NWeai1 2,9997 TWEED 900

Type of Surveyis)

/l iRfbosirJ^ c LC.C~I fie t-if\(jMffj^(C^ f f~if)6t\)i2,~T~(Cj iS'UAu'G. y*Township or Area

Claim Hoider(s) Prospector's Licence No.

Address

Survey Company |Date of Survey (fror

OlCitf,SM S"U^-V-XtyS •f'/VZ-OCXcri'SV/v/ 6 r 0 t H .^j Day j Mo. | Yr.

Name and Address of Author (of Geo-Technical report)

Credits Requested per Each Claim in Columns at rightSpecial Provisions

For first survey:

Enter 40 days. (This includes line cutting)

For each additional survey: using the same grid:

Enter 20 days (for each)

Man Days

Complete reverse side and enter total(s) here

Airborne Credits

Note: Special provisions credits do not apply to Airborne Surveys.

Geophysical

- Electromagnetic

- Magnetometer

- Radiomotric

- Other

Geological

Geochornicol

Geophysical

- Electromagnetic

- Magnetometer

- Radiometric

- Other

Geological

Geochemical

Electromagnetic

Magnetometer

Radiometric

Days per Claim

Days per Claim

-—— ——

Dnys per Claim

Wt.

WO

Expenditures (excludes power stripping)Type of Work Performed

Performed on Claim(s)

Calculation of Expenditure Days Credits Totnl

Total Expenditures Days Credits

n Si to) iTotal Miles of line Cut /b li. ?(, Day Mo. | Yr. j

Mining Claims Traversed (List in numerical sequence)Mining Claim

Prefix

L:'- '

; - v ^

Number

ctsf^atCj^t) lo 3 Z.

95^33

Q^^h'3^

q55-b3^

QS^bZb

9^^(o3"7

9^S"t 3 S"

v^b39Q^'^foHOq^s-'bqr

c/^i/^r

95^/3 1q 59/32,

c?5-i 10 3

*rrq i^y

Expend. Days Cr.

Mining ClaimPrefix

t-

Number

—————————————

'

Expend. Days Cr.

^ . . .

TWEED TOWNSHIP

\

Ontario

r

Ministry ofNorthern Developmentand Mines

Geophysical-Geological-Geochemical Technical Data Statement

TO BE ATTACHED AS AN APPENDIX TO TECHNICAL REPORT |FACTS SHOWN HERE NEED NOT BE REPEATED IN REPORT

TECHNICAL REPORT MUST CONTAIN INTERPRETATION. CONCLUSIONS ETC. |

Type of Survey(s) Township or Area TUfiSP Claim Holder(s)

ftriO Mfl CWgTK.

IPA&ou/VCCS

.^ ua PCSurvey CompanyAuthor of Report Sn-ve fear r*

Address of Anthnr ortTm(Q (b3 iTiHHtttf

Covering Dates of Survey.

Total Miles of Line Cut.—

"2. b/ gio - ntC it/fc.(linecutting to office)

SPECIAL PROVISIONS CREDITS REQUESTED

ENTER 40 days (includes line cutting) for first survey.ENTER 20 days for each additional survey using same grid.

Geophysical—Electromagnetic.—Magnetometer_—Radiometric__—Other——————

DAYSper claim

Geological.Geochemical.

AIRBORNE CREDITS (Special provision credit* do not apply to airborne turveyi)

* a RWtrnmagnftir MO(enter dayi per claim)

HATF.. Ap^/ 21/SIAuthor of Report or Agent

Res. Geol.. .Qualifications.Previous Surveys

File No. Type Date Claim Holder

MINING CLAIMS TRAVERSED List numerically

(prefix) (number)

L9.S-f.fe3.?..

M t?

l

L f1 S ''l l 3

TOTAL CLAIMS.

837 (65/12)

December 2, 1987 File: 2.9997

Glen Auden Resources Limited Box 1637Timmins, Ontario P4N 7U8

Attention: Ms Nadla Calra

Dear Sirs:

Re: Airborne Geophysical (Magnetometer and Electromagnetic) Survey on Mining Claims L 955631. et al, Tweed and Bragg Townships____________________^^^^.

This Is to Inform you that the above mentioned submission has not been assessed as the survey appears to have been flown prior to the staking of the claims and therefore was not recorded by the Mining Recorder.

This material therefore 1s being forwarded to the Assessment Files Research Office without being assessed by this office. The duplicate copy 1s being sent to the Resident Geologist.

For further Information, please contact Dennis Klnvlg at (416) 965-4888.

Yours sincerely,

W.R. Cowan. Manager Mining Lands Section Mines 4 Minerals Division

Whitney Block, Room 6610 Queen's Park Toronto, Ontario M7A 1W3

DK:pl

cc: Mining RecorderKirkland Lake, Ontario

Resident Geologist Kirkland Lake, Ontario

F/GOG wood

L L 7964O7 \ 7964IQ,

. _ t - \ -p.

TOWNSHIP

M.N.R. ADMINISTRATIVE DISTRICT

COCHRANEMINING O l V f S l O

*^1inistryof Natural

MmiTtry Northern ueve

J2 M

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LOCATION MAP

Scale 1:250,000

LEGEND

Isomagnetic lines (total field)

500

100

20

- . . 500nT

100nT

20nT

10nT

magnetic depression

Magnetic inclination within the survey area:

GLEN AUDEN RESOURCES LTD.

TWEED A BLAKELOCK TOWNSHIP AREAS, ONT.

TOTAL FIELD MAGNETICS

BY DIGHEM SURVEYS ft PROCESSING INC,

DIGHEM " SURVEY

DATE: JAN. 87

GEOPHYSICfST:

JOB: 26i3

DRAFTING By:

SHEET:

Scale 1:10,000 Km

0,5 Mi

42H08NW0011 2.9997 TWEED

*i

fi

•S

'ts '

-o- . J

r". 68 ' R-S1

2-FEB-87r. CMfiGE

LOCATION MAP

490 30'

800 I5'

Scale 1:250,000

LEGEND

Isomagnetic lines (enhanced field) Frequency response ol magnetic operator

5000

1000

200

SOOOnT

JOOOnT

200nT

100nT

magnetic depression

24

20 \-

16

REJECT1^ 12Q.E

r/ AC c E PT

10 " 10 J m Cycles/metre


TWEED A BLAKELOCK TOWNSHIP AREAS, ONT.

ENHANCED MAGNETICSBY DIGHEM SURVEYS 4 PROCESSING INC

DIGHEM 111 SURVEY

DATE: JAN. 87

GEOPHYSICIST:

JOB: 268

DRAFTING By:

SHEET:

Scale 1:10,000 1 Km

0.5 Mi

2. 9997 TWEED 230

i/iv --r . i \i i X. -l

•^V*"-' *'-' ' . -' *y^j

,v ' ' ' ' r -I'f't 1-**-

86^037

S-***^-J i " l'. ' -i 1~ . F l S.' *~

^t ' J ^0. ^e -, ~ ".. ' a r: - t

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^wV:Lft"::i^^T '-a

fi-S l

2-FEB-87

LOCATION MAP

8 O0 15

Scale 1:250,000

LEGEND

1000

800-600

-50D

- 400 —

300250 —

200150 —

125 —

100

Contours in ohrrvmat 10 intervals per decade


TWEED S BLAKELOCK TOWNSHIP AREAS, ONT.

RESISTIVITY (900 Hz)BY DIGHEM SURVEYS 8. PROCESSING INC

DIGHEM Ml SURVEY

DATE: JAN. 87GEOPHYSICIST:JOB: 268

DRAFTING By:

SHEET:

Scale 1:10,000 1 Km

0,5 Mi

42H0BNW0011 2.9997 TWEED240

Ir iîl - vK1 "'"'t

" l -û Ji I'M * -' -j * l3 *B-*r - 54- ?1 F! ' :- -P ji IM -i-i"*"^

•#IO *W4 P?.* gl|^;'r^l '"' ;' ^.ff1 --' 1 "

i -7 ! ^'- * i-'- i M JV t:illy; i- ' Ih IvJi irf:: 4f|-i jP- 1\ -Nii W", ir H f fii * ,i MI : feu.^x^Jf^. â^-'Jj i&g^ ^-4^,^Fr1î

"i' ^ j, J" ..' l; .I^ r !r' 'N Ji

U li li

i l' ' .1..' i .û; i i l P '"P f\ V/ fL i Q'/J ' -t v -^

LOCATION MAP

Scale 1:250,000

LEGEND

Coaxial inphase 5 ppm mm

Coaxial quadrature 5 ppm mm

ANOMALYGRADE

6

5

4

3

2

1

—

EM GRADESYMBOL

0

0

9OOo

CONDUCTANCERANGE (MHOS)

-" 99

50-99

20—49

10—19

5— 9

< 5

^ Indeterminate

DIGHEM anomalies are divided into six grades of conductivity-thickness product. This product inmhos is a measure of conductance.


TWEED S BLAKELOCK TOWNSHIP AREAS, ONT.

ELECTROMAGNETIC ANOMALIESBY DIGHEM SURVEYS A PROCESSING INC.

DIGHEM "' SURVEY

DATE: JAN. 87GEOPHYSICIST:JOB: 268

DRAFTING By:

SHEET:

Scale 1:10,000 1 Km

0.5 Mi

42H38NV.'001 1 2.9997 TWEED 250

42 h08nw0011 (copy)

Engineering

tweed townships figure

survey area

miles of survey

figure ga resistivity

dighem survey

enhanced magnetics sheet

total field magnetics

survey operatons