Pyrite Zone - Coastal Gold

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Transcript Pyrite Zone - Coastal Gold

Growing
Projects
in Canada
Enhanced Exploration Targeting at
Hope Brook, Newfoundland:
November 21, 2013
Application of Multi-Disciplinary Industry
Academic Investigations
Forward Looking Statements
and Technical Disclosures
The information presented contains “forward-looking statements”, within the meaning of the United States Private Securities Litigation Reform Act of
1995, and “forward-looking information” under similar Canadian legislation, concerning the business, operations and financial performance and condition
of the Company. Forward-looking statements and forward-looking information include, but are not limited to, statements with respect to the estimation of
mineral reserves and mineral resources; the realization of mineral reserve estimates; the timing and amount of estimated future production; costs of
production; capital expenditures; success of exploration activities; permitting time lines and permitting, mining or processing issues; government
regulation of mining operations; environmental risks; unanticipated reclamation expenses; title disputes or claims; litigation liabilities; and limitations on
insurance coverage.
Generally, forward-looking statements and forward-looking information can be identified by the use of forward-looking terminology such as “plans”,
“expects” or “does not expect”, “is expected”, “budget”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates” or “does not anticipate”, or believes”,
or variations of such words and phrases or state that certain actions, events or results “may”, “could”, “would”, “might” or “will be taken”, “occur” or “be
achieved”. Forward-looking statements and forward-looking information are based on the opinions and estimates of management as of the date such
statements are made, and they are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of
activity, performance or achievements of the Company to be materially different from those expressed or implied by such forward-looking statements or
forward-looking information. Although management of the Company has attempted to identify important factors that could cause actual results to differ
materially from those contained in forward-looking statements or forward-looking information, there may be other factors that cause results not to be as
anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could
differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements and
forward-looking information. The Company does not undertake to update any forward-looking statements or forward-looking information that are
incorporated by reference herein, except in accordance with applicable securities laws.
Dr. Bill Pearson, P.Geo. who is a Qualified Person as defined by NI 43-101 and reviewed and approved the scientific and technical information contained
in this presentation.
Cautionary Note to U.S. Investors Concerning Estimates of Measured, Indicated or Inferred Resources.
The information presented uses the terms “measured”, “indicated” and “inferred” mineral resources. United States investors are advised that while such
terms are recognized and required by Canadian regulations, the United States Securities and Exchange Commission does not recognize these terms.
“Inferred mineral resources” have a great amount of uncertainty as to their existence, and as to their economic and legal feasibility. It cannot be assumed
that all or any part of an inferred mineral resource will ever be upgraded to a higher category. Under Canadian rules, estimates of inferred mineral
resources may not form the basis of feasibility or other economic studies. United States investors are cautioned not to assume that all or any part of
measured or indicated mineral resources will ever be converted into mineral reserves. United States investors are also cautioned not to assume that all
or any part of an inferred mineral resource exists, or is economically or legally mineable.
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Using Science to Advance Exploration
COASTAL GOLD
EXPLORATION TEAM
UNIVERSITY RESEARCH
PARTNERS
Bill Pearson, Ph.D., P.Geo.,
President & CEO
Western University
Dave Copeland, M.Sc., P. Geo.,
Chief Geologist
Blake Hylands,
Staff Geologist
Jeff Burke,
Staff Geologist
Dr. Neil Banerjee,
Assistant Professor
Erika Cayer,
Geology Student
Memorial University
Dr. Steve Piercey,
Associate Professor
Noah Rowsell,
Project Manager
Chris Hale, Ph.D., P.Geo.,
Chief Geophysicist
John Gilliatt, P.Geo.,
Consulting Geophysicist
3
GROUND GEOPHYSICS
QUANTEC TITAN 24
COD IP TEAM
Overview of Presentation

Geological Setting of Hope Brook

Use of Geophysics to outline Mineralized Zones

Application of 3-D Inversion Models

Nature & Distribution of Mineralization

Isotopic Composition of Mineralization; what it tells
us about fluid source and origin

Lithogeochemistry and Alteration; tie-in to
Geophysics and how to vector to higher grade areas

Working Exploration Model for Hope Brook
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Hope Brook Gold: The Flagship Project
 100% ownership in 1,005
claims covering 25,125 ha
 Historical production (1987 –
1997) of 752,163 ounces gold
plus copper concentrate from
1993-1997
 Current Mineral Resource
– Indicated: 12.3 million tonnes
@ 1.48 g Au/t for 590,000 oz
– Inferred: 8.3 million tonnes @
2.07 g Au/t for 548,000 oz
 Deposit hosted in SW part of
Late Proterozoic Avalon Zone
5
Geology of Avalon Zone
 Late Neo-Proterozoic (760-540Ma) assemblage of active plate
margin sequences (O’Brien et al. 1998)
 Sequences accumulated prior to development and closure of the
Lower Proterozoic Iapetas Ocean
 Most significant magmatic activity from 640-560Ma
 Volcanic and plutonic rocks in this period evolved in back-arc or
continental arc settings
 Broad association with terrestrial or marine siliciclastic sequences
 Related in time to develop of Gold mineralized systems in Avalon
Zone of which Hope Brook is a major example
 Intense post mineral deformation
6
Published Models for Hope Brook
 1985 to 1990 – BP-Selco (Colin McKenzie, Alan Yule) – Identification of
Pre-shearing, synvolcanic/intrusive Acid Sulphate Hydrothermal Alteration
Developed atop the Roti Intrusive Suite.
 1992 – Peter Stewart Ph.D. Thesis – Major Descriptive Study of the Hope
Brook Deposit and Characterization of Alteration - Postulated Importance of
Chetwynd Granite.
 1996 to 1998 – Dr. Benoit Dube (GSC) and Dr. Sean O’Brien (NLGS) –
Description of Deposit as a High-Sulphidation Epithermal System within the
Neoproterozoic Avalon Zone.
 2010 – present – Coastal Gold - Further Identification as High-Sulphidation
Mesothermal to Epithermal Deposit Developed within a Neoproterozoic Arc
System – de-mystification of the Chetwynd Granite. Commonalities with
younger world class high sulphidation systems globally.
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Hope Brook Stratigraphy and Age
After Dube et al., 1998
8
Major Gold Mineralized Structure
more than 8 km in Length
This is an
extensive
mineralized
system that is
very underexplored
9
Airborne Magnetics
Strongly silicified gold mineralized zone in late Proterozoic rocks
are marked by a prominent magnetic low (in blue)
10
Property Geology
11
Large Scale Mineralized System
 High sulphidation gold
deposit formed from a
long lived magmatichydrothermal system
 Mineralized zone open
along strike and at
depth
 Alteration pattern
similar to large scale
epithermal systems
 Considerable upside
for outlining additional
higher grade
mineralization within
extensive lower grade
mineralization
12
Helicopter
for scale
Open Pit
(behind hill)
Altered &
Mineralized
Shear Zone
500+m wide
Exploration Drill Targets at Hope Brook
13
General Lithostratigraphy
Pyrite Zone – Felsic
Fragmental, highly siliceous
with 2-15% stringer Pyrite.
30-80 metres thick
Silicified Mineralized Zone
Massive v. fine grained silica,
vuggy, microbrecciated with 24% Py and up to 4% Cp, Bn.
Cut by unaltered mafic dykes.
15-80 metres thick
Advanced Argillic Zone
Variably textured, white to grey,
pyrophyllite, alunite, kaolinite;
2-5% diss. Py. Blue Qtz
crystals, occasional preserved
felsic fragments and quartz
porphyry.
Up to 300 m thick
14
Gold Mineralization at Hope Brook
 Gold mineralization hosted in silicified zones within Late
Proterozoic Whittle Hill Sandstone – Third Pond Tuff
succession
 Two major gold-bearing stages:
– Earlier pervasive buff coloured silicification with lower grade
mineralization (~0.5 – 1.0 g Au/t) 15-80m thick
– Later vuggy grey silicification with local siliceous breccia
(>2.0 – 5.0+ g Au/t and significant Cu) 5-25m thick
15
Mine Zone Geological Section 11400E
Extensive mineralized
system that is very
underexplored
16
New Structural Model with Major Folds
240 - Connector Zone Target extends for
1,200m along strike
Drilling and geophysics have
identified a major fold
structure that closes below
surface in the Connector
Zone. This explains why the
silicified horizon doesn’t
come to surface southwest
of the existing mine where
historical drilling failed to
intersect the mineralized
silicified zone.
Section 10500 E
17
Hope Brook Gold Resource Model (Being Updated)
 590,000 Indicated and 548,000 Inferred ounces of gold are located within this model*
Newly Identified Major Near
Surface Target Zone
Mine Zone
open
open
open
open
*For full Mineral Resource Estimate, please refer to the
table and technical disclosures found on slide 11
240 Zone
Developing Improved Vectors for Exploration
Key Questions:
How to efficiently trace mineralized zones and outline
areas with strongest and most extensive silicification.
Are two stages of mineralization the result of different
events or evolution of the same hydrothermic system?
How to better target areas of higher grade
mineralization within the mineralized structure.
What is the potential size and scale of the Hope Brook
gold mineralized system?
How to best integrate new information into an enhanced
model to direct further exploration efficiently.
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Section
How to Efficiently Trace Mineralized Zones and Outline
Areas with Strongest and Most Extensive Silicification
Titan 24 Survey at Hope Brook
Former HB Mine
Major
Target
Zone
20
Extensive Resistivity Low Marks
Footwall Conductor (Blue)
How to Efficiently Trace Mineralized Zones and Outline
Areas with Strongest and Most Extensive Silicification (Cont’d)
Resistivity
21
How to Efficiently Trace Mineralized Zones and Outline
Areas with Strongest and Most Extensive Silicification (Cont’d)
3D Inversion Model: UBC DCIP3D
Conductivity
22
How to Efficiently Trace Mineralized Zones and Outline
Areas with Strongest and Most Extensive Silicification (Cont’d)
Footwall Pyrite Conductor
Geosoft 3D Voxel Model
DC Conductivity
Resistive Silicified Mineralized Zone
23
Fall 2012 Drill Program Confirmed Major Strike Extent

Completed 5,951 meters of reconnaissance diamond drilling in 21
holes

Drill program identified a major new near surface target zone in the
“Connector Zone” just 900m southwest of the former mine

Mineralized silicified zones were intersected over a strike length of
3.4km demonstrating continuity of the system and effectiveness of
targeting using geophysics

Thickness of the Connector Zone alteration is interpreted to be
similar to that of the former mine and 240 Zone

Drill Results included:
– Hole HB12-100: 1.51 Au g/t over 14m, 2.03 Au g/t over 8m, and 1.07 g
Au/t over 18.1m
– Hole HB12-101: 1.04 g Au/t over 8.5m, 1.44 g Au/t over 2.9m, and 1.35 g
Au/t over 5.6m
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Collaborative Research Project
Are two stages of mineralization the result of different events
or evolution of the same hydrothermal system?
How to better target areas of higher grade mineralization within
the mineralized structure
 Collaborative research project in progress with
University of Western Ontario and Memorial University
 Focus is to better understand nature, distribution and
origin of higher grade mineralization to aid further
exploration
 Samples selected from a fence of holes covering range
of lithologies and mineralization
 Initial results are very encouraging
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Hope Brook: Mineralogy of High Grade Au
1
Scanning Electron Microscope
•
1
Indicates elements present
include Sn, Hg, As, Pb, Fe, Si,
Cu, Au
2
Au
cp
mw
Mineral Liberation Analysis:
2
50 m
Epithermal Mineral Assemblage
•
3
Mawsonite, Cassiterite
(Both Sn minerals)
3
Au
Gold Grain Mapping
•
•
26
mw
Fine grained 2-3 microns
within sulphide grains
Typically on margins of
chalcopyrite (cp), mawsonite
(mw) and bornite (bn)
50000 m
0 m
bn
Au
cp
0 m
200 m
Hope Brook: Mineralizing Fluids
Hole HB11-023 included the highest grade returned at Hope Brook 204g/t Au and 7.98% Cu over 1.5m Core Length
 Analysis of samples from
major silicified zones across
deposit; grades from 0.5 g
Au/t to 204 g Au/t
 ALL the samples with
elevated gold are restricted
to a very narrow d18O range
 Gold mineralization at Hope
Brook was likely deposited
from a single fluid source
27
Au Grade (ppm) for HB 11-023 Outlier
0
50
100
150
200
250
13
12
Hole HB 10-003
11
Hole HB 11-013
10
δ18O (‰ VSMOW)
 Wallrock has wide range of
O isotopic values typical of
volcanic-sedimentaryintrusive rocks
Au Grade (ppm) Vs. δ18O (‰ VSMOW)
Hole HB 11-023
Hole HB 11-029
9
Hole HB 11-031
Hole HB 11-033
8
Hole HB 11-034
7
Hole HB 11-060
Hole HB 11-061
6
Hole HB 11-023 Au Outlier
5
4
0
1
2
3
4
5
Au Grade (ppm)
6
7
8
9
10
Primary Lithogeochemistry
Tectonic Discrimination Diagrams
Barrett and MacLean 1999
 Hope Brook Deposit hosted
within calc-alkaline to
transitional arc volcanic and
intrusive suite; Change in
tectonism/magmatic chemistry
key to mineralization?
400
350
Calc-Alkaline
300
Transitional
250
Calc-alkaline
to Transitional
Zr 200
Tholeiitic
150
100
 All rocks (Siliceous, Pyrite and
Argillic Alteration Zones, Roti
Intrusive Suite) lie along the
same fractional crystallization
trend and have a common
magmatic source => unified
stratigraphy
 Immobile trace element
geochemistry similar to worldclass high sulphidation and
porphyry Au-Cu deposits (e.g.
Yanacocha, Peru and Lepanto,
Phillippines)
50
0
0
10
20
30
40
50
Y
60
70
80
90
100
Pearce et al. 1984
1000
Volcanic Arc
(I-type setting)
within plate (A-type)
100
syn-collisional (S-type)
volcanic arc (I-type)
Nb
Yanacocha data from Longo et al.
(2010)
Lepanto data from Hedenquist et
al. (1997)
10
ocean ridge (OR-type)
1
1
10
100
1000
Y
Legend
Yanacocha
Lepanto
Hope Brook
Pyrite Zone
Argillic
Siliceous
Roti
Primary Lithogeochemistry
Primitive Mantle Normalized Trace Element Plots
 Expanded trace element
geochemistry very similar to
other world-class highsulphidation and porphyry Au-Cu
deposits (e.g. Yanacocha, Peru;
Lepanto, Phillippines)
 Flat HREE (right side of plot)
indicative of melting at shallow
crustal levels = HIGH HEAT
FLOW
 The right tectonic environment,
same chemistry and formation
conditions for causative
intrusions = LARGE SYSTEM!!
Rock/Extended PM 2
1000
Extended-PM-2-Sun and McD 89
100
Roti Intrusive
Suite,
Hope Brook
10
1
.1
Nb Ce Nd Zr Eu Gd Dy Er Lu
V
T h La
Pr Sm Hf T i T b
Y
Yb Al
Sc
Rock/Extended PM 2
1000
100
Intrusive Rocks
Yanacocha, Peru
Extended-PM-2-Sun and McD 89
Data from Longo et al. (2010)
10
1
.1
Nb Ce Nd Zr Eu Gd Dy Er Lu V
Th La Pr Sm Hf Ti Tb Y Yb Al Sc
Primary Lithogeochemistry
Primitive Mantle Normalized Trace Element Plots
 Pyrite Zone and Siliceous
Mineralized Zone show
alteration but same REE plot
as Roti Intrusive.
 Shows that the Silicified and
Pyrite Zones Developed from
a similar parent magma to
the Roti Intrusive Suite.
 Provides a linkage between
conductive Pyrite Zone and
Mineralized Silicified Zone.
i.e. conductors act as a good
proxy for mineralized zones.
Rock/Extended PM 2
1000
Extended-PM-2-Sun and McD 89
100
Pyrite Zone,
Hope Brook
10
1
.1
Nb Ce Nd Zr Eu Gd Dy Er Lu
V
T h La Pr Sm Hf T i T b Y Yb Al Sc
Rock/Extended PM 2
1000
Extended-PM-2-Sun and McD 89
100
Silicified Zone,
Hope Brook
10
1
.1
Nb Ce Nd Zr Eu Gd Dy Er Lu V
T h La Pr Sm Hf T i T b Y Yb Al Sc
Lithogeochemistry and Alteration
 Intense alteration zone
outlined between the Main
Zone and 240 Zone.
Near-surface
Target Zone
 Alteration typified by Nadepletion and elevated
major element alteration
indices (e.g. CCPI –
Chlorite-Carbonate-Pyrite
Index).
Gold Resource
<0.5% Na surface
marking zone of Nadepletion
0.5 g Au/t cut-off
 Alteration zone tracks SW
towards the 240 Zone and
its up dip extension.
Near-surface
Target Zone
 Large untested, nearsurface Exploration Target.
Gold Resource
Models in Target-ARCGIS
0.5 g Au/t cut-off
CCPI>80 marking zone
of Au proximal
Alteration
Key Points
 Lithogeochemistry and alteration support and enhance the
geophysical interpretation
 Lithogeochemistry confirms linkage between mineralized silicified
zone and conductive pyrite zone  Validates use as geophysical
marker
 REE patterns, clay mineralogy and isotopic data indicate a dynamic
mesothermal to epithermal environment
 Comparable REE and alteration patterns to world class high
sulphidation systems in similar tectonic environments
 Potential size and scale of the Hope Brook
mineralized system is much greater than
previously recognized
32
Hope Brook Deposit Model
After Dube et al., 1998
High-Sulphidation Mesothermal to Epithermal
33
Hope Brook Origin – Working Hypothesis

Fluids responsible for all gold mineralization had a
similar geochemical composition and are likely the
result of a single large system

Overall low d18O values suggests the possibility of
hotter fluids than might be expected at the top of the
system i.e. mesothermal – epithermal level

Mineralogy is epithermal in character but textures and
isotopes indicate deeper level in system
34
Implications for Hope Brook Exploration

Mineralization likely formed by major magmatichydrothermal system

Mineralizing system likely initially mesothermal then
became emergent to more epithermal but not shallow

Age of mineralization possibly correlative with Roti
Intrusion – 563+/-4 Ma (Dunning et al., 1988)

Pyrite zone confirmed as effective geophysical marker

Lithogeochemistry appears to provide best vector to
areas of potential higher grade mineralization
35
Conclusions





Geological, geophysical, geochemical and isotopic data
have better characterized overall mineralizing system
Collaborative research project enhanced knowledge of
mineralogy, alteration and likely fluid source
Hope Brook is a far bigger system than previously
believed
Exploration has just scratched the surface – vectors have
been developed for more efficient targeting
3-D technology for geophysics, geology and alteration are
valuable tools to aid interpretation and develop predictive
models for exploration
Use of Science and 3D Technology has
Greatly Enhanced Exploration Efficiency
36