aerial geographical magnetic mapping

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42H08NWe011 2,9997 TWEED 020
INrKKPRbTATlON HEFUHT
OF THti ELhUnOMUNbiriC/MAUNEl'lC SUKVhY
flown by
Uighan Surveys * l^rocessing Inc.
tor
GLEN AUDEN KESUUHCfiS UMi'i'fclJ
Blakelock Township
by
Steve Kilty and Nadia Caira
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RECEIVED
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l MKHKG LANDS SECTION
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42H08NW0011 2.9997 TWEED
020C
TABLE OF CQNfENfS
PAGE
SUMMARY AND REOCMV1EN3ATIONS. . . . . . . . . . . . . . . . . . . . . . i
INfRCOUCriON. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l
PROJECf IJOCATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
PROPERTY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SURVEY OPERATONS AND PROCEDURES. . . . . . . . . . . . . . . . . . 3
Instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Survey Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
SBCriON I:
SURVEY RESULTS
OONDUCIXDRS IN THE SURVEY AREA. . . . . . . . . . . . . . . . . 1-1
SECTION II:
mCKGRQUND INI-OUM4TION. . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-1
ELIO1CMAGNETICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-1
Geometric Interpretation..................... 1 1-2
Discrete Conductor Analysis.................. 1 1-2
X-type Electromagnetic Responses............. 11-10
The Thickness Parameter . . . . . . . . . . . . . . . . . . . . . . 1 1-11
Resistivity Mapping. . .. . . ....... . . . . .... . ... . 11-12
Interpretation in Conductive Environments.... 11-16
Reduction of Geologic Noise.................. 11-18
EM Magnetite Mapping. . . . . . . . . . . . . . . . . . . . . . . . . 1 1-19
Recognition of Culture....................... 11-21
TOfAL FIELD MAGNETICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-24
VLF-EM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1-27
MAPS ACCOMPANYING! THIS REPORT
APPENDICES
A. The Flight Record and Path Recovery

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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

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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.
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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

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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).
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TWEED-BRAGG TOWNSHIPS - 80 CLAIM BLOCK
BRAGG TOWNSHIP
Claim Number No. Recording Date
835834-835835 2 December 11, 1985
835777 1 December 11, 1985
835444 1 December 11, 1985
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TWEED TOWNSHIP
Claim Number No. Recording Date
860978-861037 60 January 15, 1986
835773-835776 4 December 11, 1985
835830-835833 4 December 11, 1985
835836-835843 8 Decaifoer 11, 1985
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The claims are in the process of being transferred into Glen
Auden Resources Limited name.
BLAKELOCK TOWNSHIP -87 CLAIM BLOCK
Claim Number No.
L859831-L859874 44
L860300-L860303 4
L860312-L860315 4
L860321 1
L860326-L860354 29
L864701-L864702 2
L864705-L864706 2
L864708 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
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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
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l * 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
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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
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to become negative, the apparent conductance and depth of EM
anomlies may be unreliable.

11. CONDUCTORS IN THE SURVEY AREA
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l * SBCTIQN I: SURVEY RESULTS
l The 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.
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The 87 claim block of Glen Auden Resources Limited covered
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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
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the 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
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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.
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n 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
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l 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.
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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.
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m . 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
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use of this model. A later section entitled Resistivity
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m Mapping describes the method further, including the effect
l of using it on anomalies caused by discrete conductors such
as sulfide bodies.
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m Geome tr i c in terpre ta 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.
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17. Conductor
location
Channel CXI
Channel CPI
Channel DIFI
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Interpretive ^ D E D T
symbol
r s rConductor: -* | L,
T C
0D : vertical dipping vertical dipping sphere;
- thin dike thin dike thick dike thick dike horizontal
E s probable
conductor
beside a
stronger 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 conductor
large fenced G B wide conductiye rc;k
orea unit buried under
resistive cover
. E- edge effect from wide
conductor
variable 1/2 ^'/4
Figure TT -i Typical DIGHEM anomaly shapes

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Table I 1-1. EM Anomaly Grades
Anomaly Grade Mho Range
6 > 99
5 50-99
4 20-49
3 10-19
2 5-9'
1. < 5
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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 its
short coil separation, tends to yield larger and more
accurate conductance values than airborne systems
having a larger coil separation.

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l ^rcan yield discrete anomalies with a conductance grade (cf .
Table II-1) of 1, or even of 2 for conducting clays which
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* 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.
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m 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
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(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,
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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
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number of factors which can produce an error in the depth
estimate, including the averaging of topographic variations
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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
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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
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^resistivity and depth for a conductive earth (half space)
model, which is suitable for thicker slabs such as thick
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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

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)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
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26. - 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.
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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.

28. - 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
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29. - 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.
l
The 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
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30. - 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
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noise. - The recognition of a bedrock conductor in a
t
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

32. - 11-10 -
selected anomalies on channel CDT are discarded by the
geophysicist. The automatic selection algorithm is
4
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

33. - 11-19 -
distributed throucjliout a survey area, the inphase EM chan
nels may continuously rise and fall reflecting variations
t
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 magne t i te mapping
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

34. ~ 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 weight
i
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 multi-
coil airborne electromagnetic system: Geophysics,
v. 46, p. 1579-1594.

35. - 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

36. . - 11-22 -
l tor is cultural. However, care must be taken to ensure
that the conductor is not a geologic body which strikes
l across a power line, carrying leakage currents.
l 2. 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,
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37. l
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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.

38. 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.
l
l 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
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39. l
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- 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

40. - 1I-2G -
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Figure E"2 Frequency response of magnetic enhancement
J operator.
1
1

41. 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.
l
l ' 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

42. - II-2U -
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!; : jj lii! 2i :; : ,l; l; ; j:;! i; ':
li tJM 5 11:; t J - 1!| L
j r *""' i! i 'i;'"!'
1 " i l1 ' - -' r i II
.: .: i|i'-.... , ;i
iiiirj5p|.! i. , ij, J |,!
j | .i .l!, li.': II i i
' ! !i i'"'y :| !".|'
t :ji| j ''"i* LI '
1 L in, . i, ,. il. l
i |
lo-1
1 CYCLES X METRE
1
Figure H- 3 Froquoncy response of VLF- EM operator.
1
1
1

43. 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 Geophysicisl
l li /f
l AB-SK-4 6 O

44. 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.
l In 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.
l
l 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.

45. l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
- A-2 -
Table A-1. The Analog Profiles
Channel
Number
CXI
CXQ
CPU
CPQ1
CPI2
CPQ2
CXS
CPS
ALT
MAGC
MAG F
VLFT
VLFQ
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)
altimeter
magnetics, coarse
magnetics, fine
VLF-total: Annapolis
VLF-quad: Annapolis
Sensitivity
per nun
2.5 ppm
2 . 5 ppm
2.5 ppm
2.5 ppm
5 . 0 ppm
5.0 ppm
13.0 ppm
13.0 ppm
3 m
10 nT
2 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)
ALT
MAG
Table A-2. The Digital Profiles
Channel
Name (Freq)
MAG
ALT
CXI ( 900 Hz)
CXQ ( 900 Hz)
CPI ( 900 Hz)
CPQ ( 900 Hz)
CPI (7200 Hz)
CPQ (7200 Hz)
DIFI ( 900 Hz)
DIFQ ( 900 Hz)
SIGT
RES ( 900 Hz)
RES {7200 Hz)
DP ( 900 Hz)
DP (7200 Hz)
Observed parameters
magnetics
bird height
vertical coaxial coil-pair inphase
vertical coaxial coil-pair quadrature
horizontal coplanar coil-pair inphase
horizontal coplanar coil-pair quadrature
horizontal coplanar coil-pair inphase
horizontal coplanar coil-pair quadrature
Computed Parameters
difference function inphase from CXI and CPI
difference function quadrature from CXQ and CPQ
conductance
log resistivity
log resistivity
apparent depth
apparent depth
Scale
units/mm
20 nT
6 m
2 ppm
2 ppm
2 ppm
2 ppm
2 ppm
2 ppm
2 ppm
2 ppm
1 grade
.06 decade
.06 decade
6 m
6 m
AB-SK-460

46. * - 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

47. 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

48. ©
Ministry of
Northern Development
and Mines
Ontario
Report of Work ^ c
(Geophysical, Geological,
Geochemical and Expenditures)
Mini
42H88NWeai1 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 right
Special 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^at
Cj^t) lo 3 Z.
95^33
Q^^h'3^
q55-b3^
QS^bZb
9^^(o3"7
9^S"t 3 S"
v^b39
Q^'^foHO
q^s-'bqr
c/^i/^r
95^/3 1
q 59/32,
c?5-i 10 3
*rrq i^y
Expend.
Days Cr.
Mining Claim
Prefix
t-
Number
—————————————
'
Expend.
Days Cr.
^ . . .

49. TWEED TOWNSHIP

50. Ontario
r
Ministry of
Northern Development
and 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.
IP
A&ou/VCCS
.^ ua PCSurvey Company
Author 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——————
DAYS
per claim
Geological.
Geochemical.
AIRBORNE CREDITS (Special provision credit* do not apply to airborne turveyi)
* a RWtrnmagnftir MO
(enter dayi per claim)
HATF.. Ap^/ 21/SI
Author 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)

51. December 2, 1987 File: 2.9997
Glen Auden Resources Limited
Box 1637
Timmins, 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 Recorder
Kirkland Lake, Ontario
Resident Geologist
Kirkland Lake, Ontario

52. F/GOGwood
L L
7964O7 7964IQ,
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TOWNSHIP
M.N.R. ADMINISTRATIVE DISTRICT
COCHRANE
MINING O l V f S l O
*^1inistryof
Natural
MmiTtry
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J2 M
TOWNSHIPBRAGG
42H88NWeeil 2.9997 TWEED

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GLENAUDENRESOURCESLTD.
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42H08NW60112.9997TWEED
REVISIONSROBERTS.MIDDLETON
EXPLORATIONSERVICESINC
for
GLENAUDENRESOURCESLTD.
Title
CLAIMMAP
TWEED-BLAKELOCKTWPS.
5(9-2
Date:FEB21,
Drawn:VK
Scale:i3ieeo
Approved:
NT.S.
File:

54. /; ; i i * ; ; x ////C—
/•i A /' ,/ |i. i fi'l11ffi-
M/-'/ nithm
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

55. *i
fi
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68 ' R-S1
2-FEB-87
r. C
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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
REJECT
1^ 12
Q.
E
r/ ACcEPT
10 " 10 J m
Cycles/metre
GLEN AUDEN RESOURCES LTD.
TWEED A BLAKELOCK TOWNSHIP AREAS, ONT.
ENHANCED MAGNETICS
BY 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

56. i/iv --r . i i i X. -l
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2-FEB-87
LOCATION MAP
8 O0 15
Scale 1:250,000
LEGEND
1000
800
-600
-50D
- 400 —
300
250 —
200
150 —
125 —
100
Contours in ohrrvm
at 10 intervals per decade
GLEN AUDEN RESOURCES LTD.
TWEED S BLAKELOCK TOWNSHIP AREAS, ONT.
RESISTIVITY (900 Hz)
BY DIGHEM SURVEYS 8. PROCESSING INC
DIGHEM Ml SURVEY
DATE: JAN. 87
GEOPHYSICIST:
JOB: 268
DRAFTING By:
SHEET:
Scale 1:10,000
1 Km
0,5 Mi
42H0BNW0011 2.9997 TWEED
240

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LOCATION MAP
Scale 1:250,000
LEGEND
Coaxial inphase 5 ppm mm
Coaxial quadrature 5 ppm mm
ANOMALY
GRADE
6
5
4
3
2
1
—
EM GRADE
SYMBOL
0
0
9
O
O
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CONDUCTANCE
RANGE (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 in
mhos is a measure of conductance.
GLEN AUDEN RESOURCES LTD.
TWEED S BLAKELOCK TOWNSHIP AREAS, ONT.
ELECTROMAGNETIC ANOMALIES
BY DIGHEM SURVEYS A PROCESSING INC.
DIGHEM "' SURVEY
DATE: JAN. 87
GEOPHYSICIST:
JOB: 268
DRAFTING By:
SHEET:
Scale 1:10,000 1 Km
0.5 Mi
42H38NV.'001 1 2.9997 TWEED 250