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ASSESSMENT REPORT
on
GEOCHEMICAL WORK ON THE FOLLOWING CLAINS
HANNA 1 HANNA 2
Located
27 AIR-KILOMETERS NORTH-NORTHWEST OF r!.:~.
ALICE ARM, BRITISH COLUMBIA j
LATITUDE 55"42' - LONGITUDE 129"38' :
N.T.S. 103P/12E
SKEENA MINING DIVISION
NORTHWESTERN BRITISH COLUMBIA
FIELD WORK BETWEEN OCTOBER 27 AND OCTOBER 31, 1981
on behalf of
HANS FOERSTER
Vancouver, 8. C.
April 6, 1982
REPORT BY: W.D. Groves, P.Eng. 15.2 - 890 West Pender Vancouver, B. C.
TABLE OF CONTENTS
INTRODUCTION
A. Property - Location, Access and Physiography
B. Status of Property
C. History
D. References
E. Summary of Work Done
TECHNICAL DATA AND INTERPRETATION
A. Field Procedure and Laboratory Analysis '
B. Stream Sediment Survey
C. Conanents on Geology, Geochemistry
CONCLUSIONS
APPENDICES
I Work Cost Statement
II Certificate
III Assay Certificates
ILLUSTRATIONS
Fig. 1 -
Fig. 2 -
Fig. 3 -
Fig. 4 -
Fig. 5 -
Fig. 6 -
Fig. 7 -
Fig. 8 -
Location Map
Claims Map
Stream Sediment Survey - Sample Locations
Stream Sediment Survey - MO and Cu (ppm)
Stream Sediment Survey - Pb and Zn (ppm)
Stream Sediment Survey - Mn and Ba (ppm)
Stream Sediment Survey - Co, As and W (ppm)
Stream Sediment Survey - Ag and Au (ppm)
3
4
6
a
Report Body
Report Body
Map Pocket
Map Pocket
Map Pocket
Map Pocket
Map Pocket
Map Pocket
-l-
INTRODUCTION
A. Property - Location, Access and Physiography
The property is situated at the headwaters of O'Neill River
approximately 27 air-kilometers north-northwest of Alice Arm.
Access is by helicopter from Kitsault (six kilometers south of
Alice Arm) or, alternatively, from Stewart, sane 30 kilometers to
the northwest. A road is presently under construction which will
link Kitsault to the B.C. highways system.
Location is shown on Fig. 1.
Elevations range from 700 meters to 1100 meters over the
Hanna 1 and Hanna 2 claim area. Topography is sub-alpine/glacial
with recent cross-cutting stream courses cutting small slot-canyons.
Vegetation consists of alpine type meadows and patches of balsam
and spruce forest.
B. Status of Property
The Hanna 1 and 2 mineral claims are presently owned by
H. Foerster of 4301 - 2390 West 1st Avenue, Vancouver. Relevant
claim information is summarized below:
Claim Name Record No.
Hanna 1 2841 (2)
Hanna 2 2842 (2)
No. of Units
20
20
The claims are situated in the Skeena Mining Division. They
are pictorially represented in Fig. 2.
-2-
C. History
This area received attention in the 1920's in the aftermath of
discoveries in the Kitsault River Valley to the east (e.g., Dolly
Varden and Torbrit silver mines). However, remote location and
snow cover hampered prospecting efforts. Two area properties, the
Vimy Ridge Group and Carpenter's claims, were actively explored
during this period. The latter, Carpenter's claims, should be some-
where in the northwetsern portion of the Hanna 2 claim, according
to an old report (Ref. 1). Free gold in quartz-sulfide cross veins
was reported as occurring on this old property.
Apparently the area underwent further exploration in the 1960's
with limited results (Ref. 3). Current interest in the area was
sparked by high geochemical stream sediment values obtained during
a B.C. Government survey (Ref. 4).
0. References
1. Minister of Mines, B.C., Annual Rep't 1923, p. N52-53.
2. Preliminary Map No. 8, Geological Compilation of the
Stewart, Anyox, Alice Arm and Terrance Areas, B.C. Dep't.
of Mines & Petroleum Resources.
3. E.W. Grove, Ph.D., P.Eng., 1981. Private Report on Hanna
Property.
4. Regional Stream Sediment Survey, B.C. 1978: N.T.S. 103P
and Part of 1030, RGS - 2 - 1978.
-3-
E. Summary of Work Done
The author and Mr. Bill Banerd (assistant) flew into the
property by helicopter from the construction camp at the terminus
of the new Kitsault access road on October 27, 1981. Thereafter
stream sediment samples representative of most of the drainage
area in the Hanna 1 and 2 claim blocks were collected, 33 altogether.
This work was hampered by severe weather conditions on the third and
fourth day in the form of an unexpected snowstorm. The author and
Mr. Banerd were flown out on October 31, 1981.
TECHNICAL DATA AND INTERPRETATION
A. Field Procedure and Laboratory Analysis
Stream sediment samples were taken by screening fine silt fmm
the middle of the stream or creek through a fine nylon mesh into a
plastic bowl. Contents of the bowl were then washed into a marked
standard kraft bag.
Acme Analytical Laboratories Ltd., 852 East Hastings Street,
Vancouver, carried out all of the test work. Standard sample
preparation consisted of drying to 6O'C and then sieving to -80 mesh.
Parts per million content of all elements (except for gold and
barium) was determined by I.C.P. (Inductively Coupled Argon Plasma).
Prior to the I.C.P. analysis, each sample (500 grams) was digested
with 3 ml. of 3:1:3 nitric acid to hydrochloric acid to water at
90°C for one hour, then diluted to 10 mls. with water.
-4-
Gold content in parts per million was determined by subjecting
ten gram samples to Fire Assay preconcentration techniques to
produce silver beads: the silver beads were then dissolved and gold
content of the resulting solution measured by atomic absorption.
This method is apparently sensitive to 0.005 ppm.
Geochemical analysis for barium consisted of digesting 0.1 gram
samples with hot NaOH and EDTA solution followed by atomic abosorp-
tion to determine ppm content.
B. Stream Sediment Survey
Results of assays on the 33 "KSH" series stream sediment
samples are plotted on Figs. 4 - 8. Stream sample locations are
presented on Fig. 3. Individual values for the eleven elements
tested are tabulated in Appendix 4 (the Geochemical Assay Certificate).
Elements analysed for are: molybdenum and copper (Fig. 4); lead and
zinc (Fig. 5); manganese and barium (Fig. 6); cobalt, arsenic and
tungsten (Fig. 7); and, gold and silver (Fig. 8).
Samples from Bonanza and Hidden Creeks (these creek names were
arbitrarily assigned by the author for ease in reference) form the
high end of the sample set (in terms of multi-element ppm readings).
Determination of anomalous levels for the elements measured is best
accomplished by incorporation of the results of the comprehensive
1978 Government Stream Sediment Survey over map sheet #103P
(Ref. 4). Computations performed on the large data set obtained
during the 1978 Government survey show the following 99th percentile
limits for samples taken in areas where the host rocks were
predominantly siltstones (oasis the case with the Hanna 1 and 2
claims).
-5-
1978 Gov't Survey 99th No. of Anomalous KSH Element Percentile Level (ppm) Samples (on this basis1
Moly ;;vyr
Zinc Silver Cobalt Manganese Arsenic Tungsten
1:: i 3:: 9
1.2 11 52
14,000 125 i
14
Since it is normal to define the top 2.5% of a population as
anomalous, reference to the 1978 99th percentile data can be consi-
dered a very conservative approach to estimating the threshhold level.
Even on this strict basis, a third of the KSH samples taken, eleven to
be exact, show anomalous levels in silver. As the chart shows, several
copper and zinc anomalies were also detected, as were a lesser number
of moly and arsenic anomalies. Dropping the 'threshhold' level limit
to coincide with the 1978 Goverment Survey 99th percentile limits
would expand the anomalous moly and arsenic class to roughly the same
size as that for silver, copper and zinc.
Reference values for barium and gold are not available because
they were not analysed for in the 1978 Government Survey. However,
values in excess of 0.020 ppm are generally considered anomalous
for gold: on this basis, 8 of the KSH samples are anomalous, with
values ranging between .020 and .060 ppm. As for barium, a quick
glance at the data is enough to indicate two definite anomalies:
KSH - 22 (at 3,000 ppm) and KSH - 27 (3,500 ppm) - both of these samples are significantly higher than any other measurement obtained
for barium over the surveyed area.
Spatially, the anomalous population divides into two groups:
KSH 8 - 12 along Bonanza Creek and KSH 28 - 31 along upper Hidden
Creek. The Bonanza Creek group shows progressively higher values,
-6-
C. Comments on Geology, Geochemistry
The highest (most anomalous) sample being the one taken furthest
upstream (KSH - 12). The Hidden Creek group's most anomalous sample
(KSH - 29) is bracketed both upstream and downstream by values which
are a little lower. Both groups show anomalous values more or less
in the same range except that zinc values are appreciably higher
in the Hidden Creek group. Most significant difference is that the
Bonanza Creek copper, zinc, gold and silver anomalies are also
accompanied by high (and also anomalous) values in arsenic.
The two barium highs (which are also associated with anomalous
silver) are unusual in that they occur at different points along
"N30OW" creek, yet the intervening sample, KSH - 24, carries a
barium content of only l/6 of the two highs it separates. Also,
there does not seem to be any correlation between barium levels and
the two major anomalous groups on Bonanza and Hidden Creeks.
Cobalt, manganese, and tungsten values over the surveyed area
are relatively uninteresting.
The Hanna claims sit astride the eastern contact of a coast-
range age stock (or batholith prominence) with the relatively
flat-lying Bowser argillites. The stock is a grey granodiorite.
The eastern margin of the stock is a contact facies, greenish-grey
in colour, due to epidote and chloritic alteration with porphyro-
blastic feldspar development.. Grain size decreases gradually over
a hundred meters to very fine-grained at the stock-sediment contact.
A 100 meter thick band of rusty-weathering hornfels marks the
sediment side of the contact. It is suspected that the contact
angle is not steep but rather moderate. East of the homfels band,
an N30°W flowing creek in a straight canyon shows more of the contact
relations: the stock margin is wedging and finger stoping into
bedding and cleavage fractures in the sediments. A "front" of quartz
-7-
veins, wedge and ribbon quartz carbonate veins and fine, light
green margin-phase diorite dykes and sills criss-cross the creek
bed. The quartz veining seems to be the forerunner of the diorite
front. The geometry of the dyke-quartz vein system penetrates and
outreaches the more coherent thermal (hornfels) front wedging along
a net of minor faults in the sediments near the contact.
It is hypothesized that the geochemical stream sediment
results indicate three distinct but somewhat spatially superimposed
sets of mineralization: a "front" of copper, gold, moly, etc. (plus
silicification) associated with the hornfels front, and a lower
temperature lead, zinc, iron, silver (some gold) sulphite front
migrating along minor faults in the sediments, and a barite-
carbonate-silver quartz vein network also near the contact. The
intrusive side of the contact shows only erratic, weak tungsten
and moly geochemistry, so the situation is not a copper porphyry
type of situation where mineralization is "ponded back" within the
margin of the intrusive (as is the case with the small Tertiary
stocks in the Kitsault area).
The mineralization of interest to the author are the low
temperature ones. Float with lead/zinc visible in a quartz-carbonate
gangue was seen In the Rich Forks Creek lower course. Some of the
wedge-ended quartz veins contain up to 25% brecciated slate.
Silver geochemistry values increased as successive samples
were taken (going upstream) on Bonanza Creek. The last sample taken
was the highest. This creek is on an N30°W lineation with the
contact creek. It is slightly inside the hornfelsed front area and
does not exhibit any quartz veining. Creek-placer concentration
of sulphides may be one factor in explaining the high sediment
anomalies.
-a-
Exploration targets for further work include the area of the
vein network on the slightly faulted contact of the diorite and/or
the late or rather flat-lying minor thrusts and cross-faults in or
near the contact area in the Bowser. Such structures might host
"Dolly Varden" type mineralization (of the same metal suite as the
low temperature mineralization). The N3O"W lineation is parallel
to the Kitsault River fault. No signs of the bricky red volcanic
unit were encountered in the area traversed.
CONCLUSIONS
The 1987 field program has successfully confirmed and extended
anomalous geochemical highs in zinc , copper and silver reported in
the 1979 B.C. Government Stream Sediment Survey. Two creeks,
"Bonanza" and "Hidden", show highly anomalous levels in zinc,
copper, and silver accompanied by lesser, threshhold to anomalous
amounts in moly, arsenic and gold. Detailed follow-up stream
sediment geochemistry is required to trace the source of these
anomalies. Thereafter a program of soil or rock geochemistry with
some geological mapping would be necessary in order to further
delineate target areas.
The two barium highs recorded along "N3O"W" creek deserve
follow-up in the same manner, particularly since they are both
associated with anomalous silver values.
APPENDIX I
WORK COST STATEMENT
FIELD PERSONNEL
W.D. Groves, P.Eng., Geological Engineer Oct. 27, 28, 29, 30 and 31, 1981 5 days @ 63OOlday
8. Banerd, Assistant Oct. 27, 28, 29, 30 and 31, 1981 5 days @ $75O/day
CAMP SUPPORT (Food, Supplies, etc.)
10 man-days @ $35/man-day
TRUCK RENTAL
7 days @ $35/day (All-found)
HELICOPTER
50% of $1228.50
GEOCHEMICAL ANALYSIS (Acme Analytical Labs.)
33 L.C.P. (multi-element); 33 Barium by AA, and 33 Gold by AA
$1500.00
750.00
350.00
245.00
614.25
327.70
REPORT COSTS
W.D. Groves, P.Eng. - Report Preparation 2 days 8 $350/day 700.00
George Toop - Drafting 18 hours @ $12/hour 216.00
Blow-ups, figure reproductions, materials, etc. 114.00
Typing - Rough and final 85.00
TOTAL COST $4901.95
Re~~~,~~-~
W.D. Groves, P.Eng. April 6, 1982
APPENCIX II
CERTIFICATE
I, WILLIAM 0. GRCVES, of # 425 - 1915 Hare Street,
Vancouver, Grit&h Columbia, do hereby certify:
1. THAT I am a consulting engineer (geological and chemical) with
an office at + 152 - 890 W. Perder, Vancouver, B.C.
2. THAT I am a graduate of the University of British CoIumbia witi
a B.A.Sc. in Geological Engineering, 1960, and a Ph.D. in Chemical
Engineering, 197l.
3. THAT I am a registered Professional Engineer in the Province
of British Columbia.
RespectfUlly submitted,
W.D. Groves, P. Eng.
DATED: Apt+ 6, 1982.
ACME ANALYTICAL LABORATORIES LTD.
TV: Archsean ReS. 152 - 890 H. Pender St., Vancouver, B.C. V66 lJ9
Assaying & T~ca Advsis 852 E. Hartings St.. “enmw3r. B.C. “6A lR6
~hone:253 - 3158
81-1769 PiI* Na _-------------- lYPC OISmlPlU 2o!!i----
GEOCHEMICAL ASSAY CERTIFICATE __ DWOUbm--------------