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REPORT ON THE c2i / 9.E INDUCED POLARIZATION
AND RESISTIVITY SURVEY
ON THE RICK CLAIM GROUP
HOLBERG, BRITISH COLUMBIA
FOR
HOLBERG MINES LTD. ‘.T: c: ‘7 _L
, ,A< ,v;lz--
BY
P. G. HALLOF, PH.D.
AND
D. B. SUTHERLAND. M.A.
NAME AND LOCATION OF PROPERTY:
HOLBERG: 2 MILES WNW OF HOLBERG, 50”, 128” NE
DATE STARTED - FEBRUARY 1, 1963
DATE COMPLETED - MARCH 10, 1963
TABLE OF CONTENTS
Part A: Note* on theory and field procedure
Part B: Report
1. Introduction
2. Prerantation of Result8
3. Mecumion of Results
Line 25tOOE Line ZO+OOE ~iria 15tOOE Line 1 O+,OOE Line 5t.OOE Line otoo
14 pageE PaJp
1
1
3
4 4 4 5 5 5 5 Line 5.1OOW
Line 1o+oow Line 15’OOW Line 2OtOOW
Department of ‘Z 6
Line 25tOOW Line 30tOOW
Mines and Petroleum Res,ourcos i
Line 35.tOOW ASSESSMENT ~~~~~~~ 7 Line 9E2 7 Line A NO. ..,..... . $%f:..z A*.;,P,.~ ..~ 7 Line B 7 Line C 8
4. Conclusions and Recommendations 8
5. Alrsessment Detaila 11
6. Certificate - Philip G. Hallof 12
7. Certificate - Don B. Sutherland 13
8. Summary of Cost 14
Part C: Illwtrations 22 pieces
Plan Map (in pocket) Dwg. Misc. 4015 Y9’-/
I.P. Data Plots hgs. 1.P. 2040-l to -21
McPHAR GEOPHYSICS LIMITED
NOTES ON THE THEORY OF INDUCED POLARIZATION
AND THE METHOD OF FIELD OPERATION
‘I
Induced Polarization as a geophysical,measurement refers
to the blocking action or polarization of metallic or electronic
conductors in a medium of ionic solution conduction.
This electro-chemical phenomenon occurs wherever
electrical current is passed through an area which contains metallic
minerals such as base metal sulphides. Normally, when current is
passed through the ground, as in resistivity measurements, all of the
conduction takes place through ions present in the water content of the
rock, or soil, i.e. by ionic conduction. This is because almost all
minerals have a much higher specific resistivity than ground water.
The group of minerals commonly described as “metallic”, however,
have specific resistivities much lower than ground waters. The
induced polarization effect takes place at those interfaces where the
mode of conduction changes from ionic in the solutions filling the
interstices of the rock to electronic in the metallic minerals present
in the rock,
1
The blocking action or induced polarization mentioned
above, which depends upon the chemical energies necessary to allow
the ions to give up or receive electrons from the metallic surface,
increases with the time that a d. c. current is allowed to flow through
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1
I
the rock; i. e. as ions pile up against the metallic interface the
resistance to current flow increases. Eventually, there is enough
polarization in the form of excess ions at the interfaces to effectively
stop all current flow through the metallic particle. This polarization
takes place at each of the infinite number of solution-metal interfaces
in a mineralized rock.
When the d. c. voltage used to create this d. c. current
flow is cut off, the Coulomb forces between the charged ions forming
the polarization cause them to return to their normal position. This
movement of charge creates a small current flow which can be
measured on the surface of the ground as a decaying potential difference.
From an alternate viewpoint it can be seen that if the
direction of the current through the system is reversed repeatedly
before the polarization occurs, the effective resistivity of the system
as a whole will change as the frequency of the switching is changed.
This is a consequence of the fact that the amount of current flowing
through each metallic interface depends upon the length of time that
current has been passing through it in one direction.
The values of the “metal factor” or “M. F. ” are a measure
of the amount of polarization present in the rock mass being surveyed.
This parameter has been found to be very successful in mapping areas
of sulphide mineralization, even those in which all other geophysical
methods have been unsuccessful. The induced polarization measurement
is more sensitive to sulphide content than other electrical measurements
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I
I
because it is much more dependent upon the sulphide content. As the
sulphide content of a rock is increased, the “metal factor” of the rock
increases much more rapidly than the resistivity decreases.
Because of this increased sensitivity, it is possible to
locate and outline zones of less than 10% sulphides that can’t be
located by E. M. Methods. The method has been successful in locating
the disseminated “porphyry copper ” type mineralization in the South-
western United States.
Measurements and experiments also indicate that it should
be possible to locate most massive sulphide bodies at a greater depth
with induced polarization than with E. M.
Since there is no 1. P. effect from any conductor unless it
is metallic, the method is useful in checking E. M. anomalies that are
suspected of being due to water filled shear zones or other ionic
conductors. There is also no effect from conductive overburden, which
frequently confuses E. M. results. It would appear from scale model
experiments and calculations that the apparent metal factors measured
over a mineralized zone are larger if the material overlying the zone
is of low resistivity.
Apropos of this, it should be stated that the induced
polarisation measurements indicate the total amount of metallic
constituents in the rock. Thus all of the metallic minerals in the rock,,
such as pyrite, as well as the ore minerals chalcopyrite, chalcocite,
galena, etc. are responsible for the induced polarizatioreffect. Some
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” oxides such as magnetite, pyrolusite, chromite, and sdme forms of
hematite also conduct by electrons and are metallic. All of the metallic
minerals in the rock will contribute to the induced polarization effect
measured on the surface.
In the field procedure, measurements on the surface are
made in a way that allows the effects of lateral changes in the properties
of the ground to be separated from the effects of vertical changes in the
properties. Current is applied to the ground at two points a distance
(W apart. The potentials are measured at two other points (X) feet
apart, in line with the current electrodes. The distance between the
nearest current and potential electrodes is an integer number (N) times
the basic distance (X).
The measurements are made along a surveyed line, with
a constant distance (NX) between the nearest current and potential
electrodes. In most surveys, several traverses are made with various
values of (N); i. e. (N) = 1, 2, 3, 4, etc. The kind of survey required
(detailed or reconnaissance) decides the number of values of (N) used.
In plotting the results, the values of the apparent resistivity
and the apparent metal factor measured for each set of electrode
positions are plotted at the intersection of grid lines, one from the
center point of the current electrodes and the other from the center
point of the potential electrodes. The resistivity values are plotted
above the line and the metal factor values below. The lateral displace-
ment of a given value is determined by the location along ,the survey
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line of the center point between the current and potential electrodes.
The distance of the value from the line is determined by the distance
(NX) between the current and potential electrodes when the measure-
ment was made.
The separation between sender and receiver electrodes is
only one factor which determines the depth to which the ground is being
sampled in any particular measurement. These plots then, when
contoured, are not section maps of the electrical properties of the
ground under the survey line. The interpretation of the results from
any given survey must be carried out using the combined experience
gained from field, model and theoretical investigations. The position of
the electrodes when anomalous values are measured must be used in the
interpretation.
In the field procedure, the interval over which the potential
differences are measured is the same as the interval over which the
electrodes are moved after a series of potential readings has been made.
One of the advantages of the induced polarization method is that the
same equipment can be used for both detailed and reconnaissance surveys
merely by changing the distance (X) over which the electrodes are moved
each time. In the past, intervals have been used ranging from 100 feet
to 1000 feet for (X). In each case, the decision as to the distance (X)
and the values of (N) is largely determined by the expected size of the
mineral deposit being sought, the size of the expected anomaly and the
speed with which it is desired to progress.
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e The diagram in Figure 1 below demonstrates the method
used in plotting the results. Each value of the apparent resistivity
and the apparent “Metal factor” is plotted and identified by the position
of the four electrodes when the measurement was made. It can be seen
that the values measured for the larger values of (n) are plotted farther
from the line indicating that the thickness of the layer of the earth that
is being tested is greater than for the smaller values of (n); i. e. the
depth of the measurement is increased.
METHOD USED IN PLOTTING DIPOLE-DIPOLE
INDUCED POLARIZATION AND RESISTIVITY RESULTS
I 2 u 4 5 6 7 8 9
Stations on line x = Electrode spread length n: Electrode seporotion
n-2 MF M.S M.S MS MS 12-4.5 2.3-5.6 3.4-67 4,5-7x! 5$-8.9
111 n-3 MS M.S M.S M~S 1.25.6 2.3-67 3,4.7,8 4.5-8.9
dpp..*nl Melo, Fador
n-4- ME M.S M~F 1.2-67 2.3-7.6 3.4 E,9 .!yiJ
McPHAR GEOPHYSICS LIMITED
REPORTONTHE
INDUCED POLARIZATION
AND RESISTIVITY SURVEY
ON THE RICK CLAIM GROUP
HOLBERG, BRITISH COLUMBIA
FOR
HOLBERG MINES LTD.
1
1. INTRODUCTION
At the request of Chapman. Wood and Griswold Limited,
Conoultants for the Company, an induced polarisation eurvey he8
been carried out near H~olberg, B.C. on behalf of Ho&erg Mine8 Ltd.
The survey covered part of a grid on the Rick Claim Group; the work
was planned to locate any u&now-n zonee of mineralisation in the area
of l tveral narrow, high-grade copper vein*. It wan hoped that a
larger volume of mineralisation might be preeent at depth.
The survey was carried out uring 200’ electrode intervale.
With this separation only w44k anomalier would be expected from the
indhMuaLnarrow v4in4;howev4r. a Isrgsr volume 0fmetaIlic min4rrltaa-
tion would be detected to depths of 200-300 fed.
1
2. PRESENTATION OF RESULTS
The induced polarisation and reristivity rewlts are ehown
on the following enclosed data plots. The remlta are plotted in the
manner dencribed in the notee preceding thin report.
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Line 25+00 Ea6t
Line 2OlOO E66t
Line lSiO0 Eant
Line 10*00 Ea6t
Line 5+00 E66t
LinQ O-100
Line 5400 Wed
Line lO+ 00 We6t
Line 15too west
Line 20100 W66t
Line 25too West
Lina 30100 Weat
Litlo 35r,oo Wsrt
Line BE2
Line A
Line B
Line c
200’ Spread8
200’ Spread8
200’ Spra8d6
200’ SpP66d6
200’ Spr68d6
200’ Spreads
200’ Spr*ad6
200’ Spr6rd6
200’ gproad6
200’ spread8
200’ Spread6
200’ Spread6
100’ Spread6
50’ Spreads
200' Spr66d6
100’ Spreada
50’ Spreada
200’ Sprsadr
200’ spread6
200’ Spread6
200’ gprard6
Dwg. I.P. 2040-I
Dwg. 1-P. tQ40-2
Dwg. I.P. 2040-3
Dwg. I.P. 2040-4
Dwg. 1-P. 2040-5
Jhg. I.P. 2040-b
Dwg. I.P. 2040-7
Dng. I.P. 2040-g
Dwg. I.P. 2040-9
Dwg. I.P. 2040-10
Dwg. I.F. 2040-11
Dwg. I.P. 2040-12
Drsg. I.P. 2040-13
Dwg. I.F. 2040-14
Dwg. I.P. 2040-15
Dwg. I.F. 2040-16
Lhvg. I.P. 2040-17
Dwg. I.P. 2040-18
Dap. I.P. 2040-19
Dwg. I.P. 2040-20
Dwg. I.P. 2040-21
AI60 sntilosed with tbi6 report i6 I.hvg. Mi6c. 4015, a pIan
map of tbc grid at 6 6caIe of 1” = 200’. The liner covered by the rurvay
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are shown on thie map. Line 9E2, Line A. Line B. and Line C were
eurvoyed to cover other areas of interest, and their poeitione are not
ehown on thie mop. The definite end poeeibla induced polarisation
anomeliee are indicated by eolid and broken bare reepectiveiy on tkie
plan map a8 well a8 the data plate. Theee bare rapreeent the ourSace
projection of the anomaloue eonee as interpreted from the location of
the transmitter end recsivar electrodee when the anomalous value8
were measured.
Since the Induced palarization meaeuroment ie eeeentially
an averaging proceee, ae are aA1 potential methode, it ie frequently
difficult to exactly pinpoint the l ouree of an anomaly. Certainly, no
anomaly can be located with more accuracy than the eproad length; i. a.
when ueing 200’ epreade the poeition of a narrow sulphide body can only
be determined to lie between two etatioae 200’ apart. In order to locate
eourcee at rome depth, larger l preade muet be ueed, with a correepond-
ing increase in the uncertaintise of location. Therefore, while the centar
of the indicated anomaly probably correeponde fairly well with source,
the length of the indtcatad anomaly along the line ehould not be teken to
repreeent the exact edgee of the anomaloue material.
3. DISCUSSION OF RESULTS-
The known minerelisation on the Rick Claim Croup coneiete
of eeveral emall aonee of high-grade copper mineralisation. Three
some are shown on Dwg. Misc. 4015. The liner l hewn on Dwg. Misc.
-4-
1 4015 were rurveyed in an attempt to locate other mineralised xonee that
might be larger md therefore of more commercial interoet.
To the we&. the northern parta of the Unoe extoaded into
the low, ewampy ground north of the fault. The surface rosietivitiea
were low in this area and the voltages to be measured in the I.P. survey
were much reduced in magnitude. These lines ore also the cloweet to
the Nolberg RCAF Base. and the electrical noiee created by the inrtella-
tion at the Baee warn large. Due to the low voltagee on there linem.
meaeuremente were difficult, or impoeaiblt; on many of the liner only
the mearurameate for n=l and a=2 could be made. Others of the meaaure-
merits are doubtful due to the aoiea.
I Line 2si-OOE
This is the taeternmort line surveyed. Two moderate magni-
tude, but definite, I.P. anomaliae art indicatsd by thaws rewlte. One
anomaly ia centsred at 16N at the fault, but the other ie at 22N ta 24N,
where swamp covers the surface.
Line 20+00E
Only a l hort part of We line was eorveyed. Although the
background I.P. effecta are somewhat larger then ueual, they are not
really anomalous .
Line 15tOOE
Tbie line is aleo abort. The I. P. beokground 10 high, and
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there ie a poorly defined anomaly at 16N.
There am no d4fiaitely ammalous I. P. 4ffeetm on this
line.
Line 5?OOE
There ir a shallav, narrcm anomaly that should be checkad
with shorter spreads between 1 ON and 12N.
Thin line passee near the known copper ahowbga. Thera
arc mvaral weak 1.F. anomalie* just north of the baeoline, over tha
showing@. The44 affects would probably increase in magnitude if the
mearurementr w4fe repeated using shorter elactrede intorvale. There
ir also a deflnlte increare in the effects at depth at 6N to SN.
Line 5toow
Ths reeult8 on thie line indicate an anomaly that 18 @hallow
at 4N to 6N. This is somewhet north of the knewa mineralisation. Thsro
ir some indication that the son4 increosem in width at depth.
Lb%4 1o+oow
The shallow, narrow anomaly at 0.4 00 to 2N on thim line cot-
rolatee with known miaerelieation. There lr alro the anomaly at depth
at 4N to 6N, that is at the fault, and correlates with the anomalies to the
ea6t.
-6-
Line 15+OOW
The anomaly on tbie liae ie very similar to that on Liae 5+OOW.
The enomely correlates with the fault, cad the effects increase slightly
with depth.
Liue ZO+OOW
There is no defiaite eaomely at the fault on tbie line. H~w4ver.
there ir a feult at depth at 1tN to IQN in the area coverod by the l wemp.
The reeietivitiae at depth in thb area arc) low, md th4 1-P. effect8 are
moderetely high.
Line 25+00W
0
There ie a narrow aaomaiy at 0 to ZS on thir line that eorrefrtcs
apprcudmately with the fault. However, it would have to be detailed with
shorter electrode intervale before it caa be fully evaluated.
Ta the north, the rerlrtivities are low rr oa Lhs 2O+OOW, but
the I. P. effects are not as large. Ssv4ral of tb.e measurements could not
be made because of the noise, but th4 I.P. values seem to indicate a high
background rather tbaa an eaomaly.
The reeulte uoiag 200’ electrode intervals oa tbie liae suggeet
a broad aoae of slightly anmtaaloue 1.X’. effocto north of 6N. H4w4ver,
the meaeuromeats with 100’ interval. and 50’ iatsrvele indicate two narrow
anomali48 within this moae .
-7 -
‘I
The narrow anomaly at 4N to SN IS definite with 100’
spreads, but only the top iii evident with 50’ epreode. Therefore the
top of the mouree ie probably 50’ or more deep.
The anomaly at 12N to 13N appeare to be eomewhat broader,
and the 50’ spread raoultr do not indicate the enomaly 81 clearly.
Line 35+OOW
The 200’ l prerd remlta on thio line show an anomaly at
depth at 2N, and a elngle high value at depth at SN to 10N. The 100’
spread rem&s ehow two definite anomalieai they are cantered at 9N to
10N end 13N to 14N. Both anomrlfefi suggeet rome depth to the top of
the source .
When the rerultr were repeated ueing SO’ electrode intervals,
the anomaliee can &ill be eeen. but the pattern0 are not ae definite, eug-
getting that there ia mome depth to the eource of moat of the aaomaly.
Line 9EZ
There arc no I.P. effecte on this line.
Line A
There are no definite anomaliee on thie line.
Line B
Several weak anomeliee are indicated on thie line, but further
meaouremento would be required to completely evaluate their importance.
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”
I
Line c
The anomaly at depth at 0 to 4s on this line correlates with
a hnilar anody OA Line B.
4. CONCLUSIONS AND RECOMMENDATIONS
The induced polarieetion meaeuremento on the recoanaiseancs
grid on the Rick Claim Group gave only week anomalies over tbe known
mineralizatloa. The known veine are quite aarmw, and the electrode
l eparatione ueed are much greater then the width of mineralisation.
However, other aaomalie8 were lo-ted by the eurvey and \
theee & be due to larger volumse of mineralisation. The follotig
drill programme, consisting of 3,000 to 4,000 feet of drilling hae been
planned to teet the meet important of theee anomalies.
D. D. H. I1 - Line 5W, 715ON, drill -45’ couth for 550 feet
Tbie anomaly lice immediately north of the known mineralised
wine. The anomaly ie not rtrong, but it ie definite and the hole hae
been #potted to te8t the upper portion of the eource. However, the 1-P.
effect* do increase with depth and if the source in of economic interest.
a hole to teat the source at greater depth ehould be drilied.
D.D.H. 112 - Line lOW, 8tOON. drill -45O south for 600 feet
The eouree of thie anomaly doee AOt come ae close to the
surface am the source on Line 5W end consequently a deeper hole has
bean #potted.
- 9 -
D.D.H. 13 - Line 35W, 10+50N, drill -45* 6outh for 220 feet
Thim strong, relatively narrow anomaly ir well out in
the volley and therefore there ir no geologic information,
D. D.H. #4 - Line 3OW, S+5ON, drill -45’ 6outh for 250 feet
This anomaly ia similar but ir not aa strong. Tba
r86utt6 with 50 foot spread6 BUg@Bt that the 6ource in romewhat
deeper and therefore a 1onSer hole i6 required.
D. D.H. #5 - Line 35W, 14tOON. drill -45’ 6outh for 250 feet
Thi6 hole ha6 been 6potted to determine the eau6e of the
high background I.P. effects mea6ured north of tke narrow sources
on Lines SOW and 35W.
D. D. H. #6 - Line 25E, 1&50N, drill -45. south for 500 feet
This anomaly ir er6t of the known mlnerali6ation. The
az10mabu6 pattern is not definite, but the vahe8 are of moderate
magnitude. Therefore a 6ingle long hole ha6 heen Bpotbd to t86t the
6ource of the anomaly at depth.
D, D.H. 17 - Line C, 1~50s. drill vertical for 400 feet
Thl6 weak anomaly occurs north of the knwns mineraba-
tiou in an area where the ba6ie rock6 are believed to underlie an up-
certain thiekne66 of lime6tone. TbS 6OUfC8 Of thfr Wd UtOXll~y i6
indicated to be at depth and the vertical hole ha6 been Ipotted to determine
- 10 *
‘I
I
its source and pommibly the thickneaa of the limeatone.
The drill holes dewribed above have been apotted to teat
the mont important anomalier. If any ancourrgemcant is obtained then
the following drill holea should alro be considered.
D. D.H. #S - Line ISE, 18t5ON. drill -45’ couth for 500 feet
Thim anomaly is similar to the anomaly on Line 25E and
only the eaetern edge of the anomaly is indicated.
D.D.H. 19 - Line lSW, 7+5ON, drill -45’ @out& for 450 feet --
This anomaly ie very similar to that on Line 5W but is of
lower magnitude.
McPHAR GEOFHYSICS LIMITED
Philip G. Hallof, Geophyaiciat .
D. B. Sutherland, Geophysiciet.
Dated: April 4, 1963.
- 11 -
ASSESSMENT DETAILS
PROPERTY: Rick Claim Group
SPONSOR: Holbcrg Minea Ltd.
LOCATION: Holberg. Vancouver L~lawl
TYPE OF SURVEY: Induced Polarisation
OPERATING MAN DAYS: 42.50
EQUIVALENT 8 HR. MAN DAYS: 73.75
CONSULTING MAN DAYS: 4.0
DRAUGHTING MAN DAYS: 5.0
TOTAL MAN DAYS: 82.75
CONSULTANTS:
MINING DIVISION: Nanaimo
PROVINCE: Britieh Columbia
DATE STARTED: February 1, 1963
DATE FINISHED: March 10. 1963
NUMBER OF STATIONS OCCUPIED: 250
NUMBER OF READINGS TAKEN: 1,752
MILES OF LINE SURVEYED: 7.24
P. G. Hallof, 5 Minorca Plree, Don Mill*, Ontario D. B. Sutherland, 412 Eglinton Avenue, Eart. Toronto 12, Ontario
FIELD TECHNICIANS: P. Bauden, c/o Forest Raaprr’a School. Dorset, Ontrrio Five helwrr supplied by client
DRAUGHTSMEN: F. R. Peer, 38 Torreno Avenue. Toronto 6, Ontario R. MacKsnsis, 55 Shannon Drive, Scarborough, Ontario
McPHAR GEOI?WYSICS LIMITED
D. B. Sutbwland, Goophysicimt.
Dated: April 4, 1963.
- 12 -
CERTIFICATE
I. Philip George Hallof, of the City of Toronto, Pwvince Of
Ontario, do hereby eartify that:
1. I am a geophyaiciat residing at 5 Minorca Place, Don Mills
(Toronto). Ontario.
2. I am a graduate of the M,assachusetts Institute of Technology
with a B.S. Degree (19S2) in Geology and Gaophyrics. and a Ph.D. Degree
(1957) in Geophyoico.
3. I am a member of the Society of Exploration Gsophysicimtr
and the European Aooociation of Exploration Gaophyricists.
4. I bave beon pr8ctiaing my prof*snlon for ten years.
9. I have no direct or tndiract inters& nor do I expect to receive
any iat4reet. direct or indir4ct. in the property or aocuritiem of Holbrg
Mines Ltd.
6. The statements made in this report are bared On a rtudy Of
publirhed literature and unpublished private report6 and geopbysieti data.
Dated at Toronto
This 4th day Of April 1963 Philip G. Hallof, Ph. D.
- 13 -
CERTIFXCATE
I, Don Benjamin Sutherland of the City of Tom&a, Province
of Ontario, do hereby certify that :
1. I am a geophymicirt residing at 412 Eglinton Avenue, Eset,
Toronto 12, Ontario.
2. I am a graduate of the University of Toronto in Phyaice
and Geology with the degree of Bachelor of Arte (1954)l end 8 graduate
of the University af Toronto in Phyrice with the degree of Master of
Arta (1985).
3, I am a member of the Society of Exploration Geophysicists
and a member of the European Association of Exploration Geophyeiciete.
4. I have be- practistng my profe*doa for over swen year@.
5. I have no direct or indirect interelt, nor do I exprot to
receive any iatereet dimctly or indirectly, in the property or eecuritiee
of Holberg Mines Ltd.
6. The statements mad8 in thin report are based on a etudy of
published geological literature and uapubliahod private report&
Dated at Toronto
Thie 4th day of April 1963
- 14 -
SUMtvfARY OF COST
27-l/2 dsyr 0perating @ $165.OO/day lo-112 day8 Trawl. Bad Weather
b Standby @ $ 60. OOlday
Airfme Airf might Telephone and Telegraph Meals md Accommodation Supplies
$218.00 205.19
57.80 74.50 74.02
$4‘537.50
630.00
629.51
$2,
McPHAR GEOPHYSICS LIMITED
D. B. Satherland. Gaophykist.
Dated: April 4, 1963.