VTEM SURVEY IDENTIFIES 14 HIGH PRIORITY TARGETS AT MERLEAC
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ASX Announcement – 28 September 2015
VTEM SURVEY IDENTIFIES 14 NEW HIGH PRIORITY
MASSIVE SULPHIDE TARGETS AT MERLÉAC
Successful completion of VTEM survey and modeling work over southern
section of Merléac exploration licence
Numerous VTEM conductors identified within the same rock sequences that
host the high grade Porte-aux-Moines zinc-lead-copper-silver-gold VMS
deposit, confirming the high prospectivity of Merléac
Initial modelling work defined 14 ‘Tier 1’ high priority targets, a number of
which have similar geophysical characteristics to Porte-aux-Moines
Several targets lie adjacent or along strike from ferruginous outcrops
containing elevated base and precious metal values that may represent
other VMS deposits
VTEM anomaly extends for approximately 400 metres over Porte-aux-Moines
potentially adding significant strike length to currently defined high grade
mineralisation
Targets defined from the survey will be followed up with ground EM, soil
geochemistry and drilling
Variscan Mines Limited (ASX: VAR) is pleased to announce that it has completed modelling of a
large, heli-borne, Versatile Time Domain Electromagnetic survey (VTEM) survey recently carried
out by its wholly owned European subsidiary Variscan Mines SAS over the southern section of its
Merléac exploration licence in Brittany, France.
The VTEM survey was designed to test the key target areas in and around the high grade zinclead-copper-silver-gold Porte-aux-Moines VMS deposit that has been the focus of recent Variscan
work.
The survey covered approximately 60 strike kilometres of prospective volcanics and sediments
known to host VMS mineralisation to provide an initial geophysical test for the presence and
geometry of potential sulphide zones.
The VTEM survey successfully extended the potential strike length of high grade mineralisation at
Porte-aux-Moines and defined a number of new targets within three belts across the Merléac
licence, possibly representing base and precious metal bearing zones similar to those found at
Porte-aux-Moines.
ASX Code: VAR
Web - www.variscan.com.au
Previous work
Recent work by Variscan within the Merléac exploration licence has focussed on the high grade
Porte-aux-Moines zinc-lead-copper-silver-gold deposit where resampling of available old BRGM
(Bureau de Recherches Géologiques et Minières - the French geological survey) core recorded a
number of high grade, zinc-dominant, polymetallic intersections such as 31 metres @ 10.4% zinc,
2.1% lead, 1.2% copper, 105.5 g/t silver, 1.0 g/t gold from 236 metres (including 8 meters @
25.0% zinc, 5.4% lead 1.6% copper, 208.5 g/t silver, 1.39 g/t gold from 236 metres) in PAM5
(see ASX announcements 19 May, 20 and 29 July 2015).
Porte-aux-Moines exhibits many of the classic geological features found in other VMS deposits, in
particular the possibility for a cluster of sulphide lenses within the project area. Logging of the BRGM
holes has recorded multiple intersections of polymetallic mineralisation indicating perhaps three
mineralising events over a 50 meter interval within the mine sequence. This suggests the scope for
the discovery of a stacked massive sulphide system and provides encouragement that Porte-auxMoines could be significantly larger than currently defined.
In addition, the regional potential within the Merléac licence for additional VMS deposits is
considered excellent. Porte-aux-Moines is hosted within a sequence of vitric tuffs and pyritic black
shales (the mine sequence) located in a bimodal sequence of felsic and intermediate/mafic
volcanics. This sequence of rocks can be traced for approximately 80 kilometres along strike and
within structurally repeated blocks in the Merléac licence.
Within these rock units Variscan has defined outcropping gossanous zones containing highly
anomalous base and precious metal values interpreted to represent the oxidised expressions of
underlying sulphides (see ASX announcements from 8 December 2014 and 5 February 2015).
Some of these gossans were previously mined by shallow open pits for iron up until the 19th century
and generally have not been explored below the iron oxide cap aside from shallow BRGM drilling in
some locations.
VTEM programme
To help target VMS mineralisation around Porte-aux-Moines and within the region, Variscan recently
completed a large heli-borne electromagnetic (VTEM) survey covering approximately 160 square
kilometres of the southern section of the Merléac licence (Figure 1), testing about 60 strike
kilometres of the Porte-aux-Moines host stratigraphy.
Data produced from the survey has been now been modelled by Resource Potentials Pty Ltd, an
independent geophysical group specialising in the processing of VTEM. This work has generated a
large number of conductive anomalies within the survey area (Figure 1), many of which are due to
subsurface electromagnetic (EM) responses.
The survey A. Detected the Porte-aux-Moines deposit which clearly stands out as a bulls-eye anomaly with
a modelled strike length of about 400 metres at the projected position of mineralisation as
defined in the old BRGM drilling and development (Figures 1 and 2). Previous work by
Variscan indicated that high grade mineralisation at the deposit extended for at least 250
metres at the -150 metre level with excellent potential to expand. This potential has been
confirmed by the results from the VTEM survey.
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ASX Announcement - 28 September 2015
B. Successfully identified 14 other 'Tier 1' targets with moderate to strong, early to late time EM
responses, in many cases similar to those generated at the Porte-aux-Moines deposit and
which are possibly caused by sulphide-rich bedrock sources.
These are as follows Target
East
(NUTM30)
North
VTEM Decay
(NUTM30) Channels (msec)
Amplitude
(pV/Am4)
PAM
VTEM-1
VTEM-2
VTEM-3
VTEM-4
VTEM-5
VTEM-6
VTEM-7
VTEM-8
VTEM-9
VTEM-10
VTEM-11
VTEM-12
VTEM-13
VTEM-14
504,979
500,128
500,139
501,088
502,227
502,724
503,734
505,487
503,973
504,862
506,783
501,869
508,245
515,515
518,630
5,348,733
5,345,487
5,345,233
5,345,830
5,345,914
5,346,031
5,344,557
5,344,579
5,347,240
5,346,673
5,347,114
5,349,275
5,346,639
5,350,366
5,351,321
Moderate
Moderate
Low
Moderate
High
Moderate
Low
Low
Low
High
Moderate
Low
Moderate
Moderate
Moderate
Mid-late time
Mid-late time
Late time
Mid-late time
Early-late time
Mid-late time
Mid-late time
Mid-late time
Early-mid time
Mid-late time
Mid time
Mid time
Mid time
Early-late time
Mid time
Strike
Estimated
length (m) Depth (m)
400
520
200
270
220
300
380
800
170
750
250
340
700
800
300
80
120
80
80
80
100
150
100
80
220
80
100
150
120
100
C. Identified approximately 50 other conductors that may be due to sulphide zones but are close
to buildings, power lines or other 'conductive' infrastructure which requires field checks to
confirm the source of the anomalism.
Figure 1: ‘Tier 1’ VMS targets over Channel 40 response plot at Merléac
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ASX Announcement - 28 September 2015
The Tier 1 conductors are located in three principal areas. These are 1. Within the main Porte-aux-Moines block, to the west and east of the deposit (targets 11, 13,
14). At the La Forges prospect (Figure 1), EM anomalism has been detected over a length of
about 800 metres immediately along strike from an area where previous float sampling by
Variscan over old iron workings had generated strongly anomalous zinc-lead-copper-gold
assays (including up to 3.7g/t gold).
2. A west-north-west oriented belt located approximately two kilometres south of Port-auxMoines (Figures 1 and 2). Eight moderate to intense anomalies (1 to 5 and 8 to10) have
been detected over a strike length of about seven kilometres. No significant previous
exploration is believed to have been conducted in much of this area.
3. A third volcano-sedimentary belt located approximately four kilometres south of the Port-AuxMoines where previous work by Variscan had identified geochemically anomalous
gossanous and stockwork material in the west of the Merléac licence. The VTEM survey
defined an intense region of conductive bedrock to the east of these prospects containing
three targets (6, 7 and 12) with strike lengths up to 800 metres.
Each of the three target regions is located within or adjacent to strongly magnetic bedrock sources
interpreted to represent either basaltic/andesitic/dacitic volcanic rocks closely related to
mineralisation at Porte-aux-Moines or intrusives that may have been the heat engines that assisted
VMS deposit formation.
Figure 2: ‘Tier 1’ VMS targets over Channel 40 response plot in the centre of Merléac licence around
the Porte-aux-Moines VMS deposit (PAM). Targets defined principally by anomalous early to midtime responses (e.g. target 8) will appear subdued on this late-time image.
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ASX Announcement - 28 September 2015
The Company is highly encouraged by the results of the survey and will commence immediate follow
up work including
Detailed modelling of the key targets by Resource Potentials to define the depth, geometry
and significance of the conductive zones,
Where required, follow up ground EM surveys to more accurately pinpoint potential sulphide
zones,
Soil or possible shallow RAB drill traverses over selected conductors, and
Drilling (possibly to be done in conjunction with drilling to extend mineralisation at Porte-auxMoines).
Yours faithfully
................................
Greg Jones
Managing Director
The information in this report that relates to Exploration Results is based on information compiled by Greg Jones, BSc
(Hons), who is a member of the Australasian Institute of Mining and Metallurgy. Mr Jones is a Director of Variscan Mines
Limited and has sufficient experience which is relevant to the style of mineralisation and type of deposit under
consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of
the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves”. Mr Jones consents to
the inclusion in the report of the matters based on his information in the form and context in which it appears.
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ASX Announcement - 28 September 2015
JORC Code – Table 1
Section 1 Sampling Techniques and Data
Criteria
Commentary
Sampling techniques
Geotech helicopter-borne VTEM system with flying height of 75-85 m and sensor height of 3545 metre. Configuration included: 26 metre diameter transmitter loop, high peak dipole
moment, 25 or 30 Hz Component BField & dB/dt
Drilling techniques
Drill sample recovery
Logging
Sub-sampling techniques
and sample preparation
Quality of assay data and
laboratory tests
Verification of sampling and
assaying
Location of data points
NA
NA
NA
NA
NA
NA
On board differential GPS with accuracy of 3m.
Data spacing and
distribution
Orientation of data in
relation to geological
structure
Sample security
Audits or reviews
Readings taken at 2-3m intervals along flight lines nominally 200m apart.
Flight lines generally oriented perpendicular across dominant strike direction of rock units and
structures where possible.
NA
Data produced from the survey was modelled by Resource Potentials Pty Ltd, an independent
geophysical group specialising in the processing of VTEM.
There has been no external audit or review of the Company’s techniques or data.
Section 2 Reporting of Exploration Results
Criteria
Mineral tenement and land
tenure status
Exploration done by other
parties
Commentary
Merléac PERM (Permis Exclusif de Recherche de Mine, a French exploration licence)
No known impediments for future exploration and development
Last significant exploration in area is believed to have been conducted by BRGM in the 1980s.
VMS potential of the region was recognised by the BRGM who conducted regional stream
sediment programmes during the mid-1970s. The Porte-aux-Moines deposit was discovered in
1975 when follow-up soil sampling and shallow drilling intersected massive sulphides.
Subsequently the BRGM conducted substantial core drilling (+9km) and underground
development on Porte-aux-Moines.
In addition, the BRGM conducted significant mapping, geochemical and geophysical
programmes around Porte-aux-Moines and regionally.
Volcanogenic Massive Sulphide (VMS) deposits
NA
NA
NA
Diagrams have been generated from Resource Potentials modelling of VTEM data.
All significant available information for the survey has been published within the report.
NA
Detailed modelling of the key targets by Resource Potentials to define the depth, geometry and
significance of the conductive zones,
Where required, follow up ground EM surveys to more accurately pinpoint potential sulphide
zones,
Soil or possible shallow RAB drill traverses over selected conductors, and
Drilling (possibly to be done in conjunction with drilling to extend defined mineralisation at
Porte-aux-Moines).
Geology
Drill hole Information
Data aggregation methods
Relationship between
mineralisation widths and
intercept lengths
Diagrams
Balanced reporting
Other substantive
exploration data
Further work
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ASX Announcement - 28 September 2015
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