reconnaissance geophysical surveys vincent township 2.9546 reconnaissance geophysical surveys
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RECONNAISSANCE GEOPHYSICAL SURVEYS VINCENT TOWNSHIP-CLAIMS #8^5986-84-5990 CAYUGA SYNDICATE
I INTRODUCTION; The following pages are a concise attempt to
present the results of Geophysical surveys completed on Claims
#845986 to #845990 inclusive,within Vincent Township. Included
here is the location and present holders of the property,instruments
used,with a brief explaination of field procedures,previous surveys
done on the property,and finally an interpretation of the results.
Also enclosed with this report are seperate profiles of each
line,as well as a complete map of each survey.
HOLDERS of CLAIMS; The, report presented here was written by
the technical personal of the Cayuga Syndicate,which is
headquartered at 360 Main St. ,V/innipeg,Manitoba. This organization
are the present holders of this property.
LOCATION: The claims surveyed are located in the north-east
sector of Vincent Township(NTS Map 42E12) and are registered as
#8/15986 to #845990 respectively,within the Thunder Bay Mining
District(Fig.l). The claims are accessible by way of Highway #11 and
various foot trails.
EQUIPMENT and PROCEDURE; The geophysical methods used on
these claims were of the reconnaissance type,that is ground based
magnetometer and VLF-EM. The surveys were conducted between June
and August 1986.
The instruments used were a Geometrics portable proton
magnetometer,model G-8l6 and a Geonics EM16 VLF-EM system.
Specifications for both instruments are given in figures 2 and 3.
A Geometrics G-856B portable magnetometer was used as a magnetic
As this report is concerned basically with recording data
for assessment purposes,no attempt will be made to probe the
theoretical aspects of the Magnetic or Electromagnetic methodology
or equipment design. A list of suitable references is supplied to
the reader wishing to pursue this line of thought.
A brief procedure used in these surveys is as follows.
For the magnetic survey,the first step is to get the base station
functioning. The base station is necessary to correct for diurnal
and micropulsation time variations. The base station is tuned in
order to acquire the best magnetic signal. This magnetic base was
found to be 60300 Gammas. The sychronization of the base clock
with the operators field clock and a time interval for readings
is then established. This interval was 60 seconds. Finally the
Auto switch is activated and the diurnal station monitor is
operational. The operator then proceeds down the line,takes and
records a reading at the station to the nearest minute. The
stations are at 25 meter intervals along north-south trending
lines,which are 100 meters apart. The total number of stations
for all five claims is 331.
The VLF-EM survey is performed by first orientating the
instrument perpendicular to the survey line in order to establish
a transmitting station for the best coupling effect. In this case
the transmitter is NAA originating from Cutler,Maine at a
frequency of 2^.0 kHz. The transmitter direction is determined
when the sound intensity is at a minimum. The next move is to
orientate the reference coil along magnetic lines,by slowly
moving the instrument back and forth until minimum sound intensity
and adjust the Out of Phase(Quadrature) component dial to further
minimize the sound. Read and record the number on the inclinometer
and the Out of Phase component dial. The operator must always face
north or in the case of north-south trending strike,one must face
west. This is necessary in order for the polarities to remain
constant through every line.
PREVIOUS WORK: As far as can be ascertained no published
evidence is available of prior work executed on these particular
claims. In the field however,there is evidence that some trenching
was done some time ago.
I INTERPRETATION; The magnetic profiles (Fig. 4-2?) indicate
in general,a low magnetic response. There are points which show
major peaks both high and low. The magnetic anomalies that are
present imply that the structure causing them,is narrow and steeply
dipping. The structure seems to trend along strike,that is in a
east-west direction and is located,in general between lines 0+00
and 18+00 West,covering a width of 100 meters,from stations 0+00
to 1+00 South. There is a southern magnetic anomaly located between
stations 4+00 and 5+00 South,along lines 18+00 to 23+00 West. The
magnetic anomalies do not correspond exactly to the VLF conductors
noted below,but they are adjacent and thus they are most likly the
result of the same geological structure.
The VLF survey shows two conductive bodies trending
roughly in a east-west direction. The northern response is found
from line 0+00 and trends north-westerly to line 18+00 West and
probably continues further beyond the boundary of these claims in
the same general direction. This conductor seems to weaken toward
the eastern portion of the property.
The southern conductor is found between lines 14+00
and 23+00 West (Fig.28-43). It trends in a east-west direction and
most likly continues further east. The two conductors are
approximately 200 meters apart. These conductors are very similar
in response,in that both the Inphase and Out Phase components show
in general,a complementary repetative pattern through all lines. The
profiles also suggest that the dip of the southern conducting
structure is relatively steep and to the north. The response
signal is in general of moderate strength and sharp,hinting at a
shallow structure in depth. The northern conductor has relatively
physical characteristics as the southern response,implying
that both conductors are the result of parallel geologic features.
From the geological evidence,there seems to be,contained
within the volcanic flows a thin belt of Iron Formation. This zone
is observable at random locations on surface between line 10+00 and
17+00 West and approximatly between stations 50 to 100 South. This
formation contains some sulphides but its magnetic susceptibility
is low. A few meters south of these exposures is found,again at
random shear zones containing up to 53d pyrite. These shear zones
are in line with an apparent topographic lineament. Both of these
structures may account for the geophysical responses encountered
on the northern portion of these claims. Therefore a possible fault
structure trending in general in a east-west direction maybe
contained within this property.
The southern conductor is not quite as obvious. Some
Carbonized Iron rich rock was observed near station J++00 South on
line 16+00 West. This may have some strike length to it. There are
also many intrusive rocks within this southern region,and the
anomaly may be a result of a lithological change.
CONCLUSIONS; The anomalous zones within these claims
will be explored in more detail in up coming field seasons. This
v/ill involve trenching and X-ray drilling. It seems however that
a major concentration of economic minerals is not likly in this
type of environment,as the large discoveries seem to occur in
general near volcanic-sedimentary contacts. This property is near
some major showings and it is for this reason that it v/ill also be
examined in future exploration programs.
4w4^^^^ * G^V^VmS' i
Scale: l cm. s 7.84 M.(A) .s 13.7 km.,___________ ^"'^ J1 fX * j.......*""* \ J-^J1 ri r ___ __ __ JBJ.
showing position of Vincent Township J ~ Mining district and location of claims
[within, township. ^^^^
Sensitivity: 1 gamma throughout range
Range: 20,000 to 90,000 gammas (worldwide)
Tuning: Multi-position switch with signal amplitude indi cator light on display
Gradient Exceeds 300 gammas/ft (increased gradient to!- Tolerance: erance to 800 gammas/ft upon request)
Sampling Rate: Manual push-button, one reading each 6 seconds
Output: 5 digit numeric display with readout directly in gammas
Accuracy (Total Field):
Twelve self-contained 1.5 volt "O" cell, univer sally available flashlight-type batteries. Charge state or replacement signified by flashing indi cator light on display.
Battery TypeAlkalinePremium Carbon ZincStandard Flashlight
Number of Readings over 10,000 over 4,000 over 1,500
NOTE: Battery life decreases with low temper ature operation.
Console and sensor: -40" to *850 C
Battery Pack: O" to *50"C (limited use to -15 0 C; lower tempera ture battery belt opera tion optional)
l gamma through O0 to *50"C temperature range
Sensor: High signal, noise cancelling, interchangeably mounted on separate staff or attached to carry ing harness
Size: Console: 3.5 x 7 x 10.5 inches (9 x 18 x 27 cm) Sensor: 4.5 x 6 inches (11 x 15 cm) Staff: l inch diameter x 8 tt lenght
(3 cm x 2.44 m)
Weight:Console (w/barteries): Sensor A signal cable: Aluminum staff:.
Lbs. 5,5 4