VTEM Suvey Underway at Merleac to Indentify New Deposits
Released
Released
Announcement PDF
ASX Announcement – 6 July 2015
VTEM SURVEY UNDERWAY AT MERLÉAC
TO IDENTIFY NEW DEPOSITS
Commencement of Versatile Time Domain Electromagnetic survey (VTEM) to
identify new volcanogenic massive sulphide (VMS) deposits within the
Merléac exploration licence.
VTEM survey will test the southern section of the licence over the high grade
Porte-aux-Moines VMS deposit and the highly prospective host rock
sequences along strike.
Previous work by Variscan has identified good exploration potential at
Porte-aux-Moines and defined a number of outcropping gossans that may
represent other VMS centres elsewhere within the survey area.
Gossans contain highly anomalous levels of zinc, lead, copper and gold.
Survey will help provide target outlines of VMS sulphide zones to be
followed up by further exploration including drilling.
Variscan Mines Limited (ASX: VAR) is pleased to announce that its wholly owned European
subsidiary Variscan Mines SAS has commenced a large heli-borne VTEM survey over the
southern section of its Merléac exploration licence in Brittany, France.
The VTEM survey has been designed to test the key target areas in and around the high grade
zinc-lead-copper-silver-gold Porte-aux-Moines VMS deposit that has been the focus of recent
Variscan work.
The survey will cover approximately 50 strike kilometres of prospective volcanics and sediments
known to host VMS mineralisation and will provide an initial geophysical test for the presence and
geometry of sulphide zones below both known outcropping gossans and those concealed under
shallow cover.
The survey is expected to be completed within two weeks with final models available in early
August.
The survey will be the first of its type flown in France for mineral deposits and will introduce stateof-art technology into the Variscan exploration programme.
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 VMS deposit where resampling of available old
BRGM (Bureau de Recherches Géologiques et Minières - the French geological survey) core in hole
PAM5 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) (see ASX announcement 19 May 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 70 kilometres along strike and
within structurally(?) repeated blocks in the Merléac licence.
Within these rock units Variscan has defined outcropping gossans containing highly anomalous
base and precious metal values interpreted to represent the oxidised expressions of underlying
massive sulphides/stockwork zones (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. They represent immediate exploration targets.
VTEM Programme
To help target potential VMS mineralisation in and around Porte-aux-Moines and the region a large
heli-borne electromagnetic (VTEM) survey has commenced. The survey will cover up to
approximately 180 square kilometres of the southern prospective section of the Merléac licence
(Figure 1). The VTEM will test approximately 50 strike kilometres of the VMS host stratigraphy for
the presence and geometry of sulphide zones below both known outcropping gossans (including
Porte-aux-Moines) and those concealed under shallow cover.
VTEM is widely considered one of the best helicopter-borne TEM geophysical systems for detecting
and imaging massive sulphide deposits in the industry. Notable recent successes in Australia
include the discovery of the Mallee Bull deposit in the Cobar Basin (see reports by Peel Mining,
ASX: PEX), and the recent Artemis discovery in Queensland by Minotaur Exploration (ASX: MEP).
The VTEM system is flown using a helicopter that tows a powerful electromagnetic transmitter and
receiver which can detect massive sulphide mineralisation to considerable depths below the surface.
The base and precious metal VMS deposits of the Merléac region such as Porte-aux-Moines are
pyrite rich and considered likely generate conductive responses to electromagnetic input as
delivered by the VTEM system. Data produced from the survey will be modelled by Resource
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ASX Announcement - 6 July 2015
Potentials Pty Ltd from Perth to generate plate simulations of the interpreted geometry of any
sulphide zones detected which may then be followed up with detailed surface EM and/or drilling.
It is expected that the VTEM survey will be completed within the next two weeks, with final modelling
and exploration target generation within the following month.
Figure 1: Key VMS prospects and outline of the VTEM survey at Merléac
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 - 6 July 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
NA
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
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 oriented perpendicular across dominant strike direction of rock units and
structures.
NA
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 for the region have been taken from published BRGM reports.
All significant information for the survey has been published within the report.
NA
Modelling of the VTEM survey data and generation of 3D shapes to describe potential
conductive sulphide sources.
Possible follow-up surface EM surveys to more accurately pinpoint sulphide zones.
Drill testing.
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 - 6 July 2015
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