Global News Release
Global
Geoscience
NEWS RELEASE 22 July, 2015 ASX Code: GSC
LARGE, HIGH-GRADE COPPER-GOLD PORPHYRY TARGET DEFINED WITHIN GLOBAL'S MANCHA PAMPA DISCOVERY, PERU
Global Geoscience Ltd
ABN 76 098 564 606
ASX Code: GSC
Current share price: $0.006
52 week range: $0.03-0.004
Issued Shares: 272M Directors Holdings: 24% Top 20 Holdings: 50%
Key Projects
Mancha Pampa Cu-Au
(100%, Peru)
Excelsior Au
(earning 70%, Nevada)
Tokop Au
(100%, Nevada)
Towers Mt, Cu-Mo
(100%, Arizona)
Lone Mt Au, Ag-Pb-Zn
(option for 100%, Nevada)
Sara Sara Cu-Mo-Ag
(100%, Peru)
Board of Directors
Robert Reynolds
Non-Executive Chairman
Bernard Rowe
Managing Director
Peter Nicholson
Executive Director
Patrick Elliott
Non-Executive Director
Registered Office
Suite 203, 161 Walker Street
North Sydney NSW 2060
AUSTRALIA
T: +61 2 9922 5800
Contact
Bernard Rowe
T: +61 4 1944 7280 [email protected]
HIGHLIGHTS
• Mancha Pampa in central Peru is a porphyry copper-gold project discovered and 100% owned by Sydney-based Global Geoscience.
• The Quillcata prospect - within the Mancha Pampa project - is an
800x1000m zone centred on a porphyry intrusion with significant copper and gold mineralisation at surface. It has never been drilled.
• Rock chip samples contain up to 2.5% Cu, 4g/t Au and 67g/t Ag.
• Reprocessing of Induced Polarisation (IP) geophysical data has recently highlighted the potential for a large, high-grade Cu-Au system at Quillcata
• An IP chargeability high forms an annular zone around a porphyry intrusion. Outcrops of mineralisation over the same zone indicate that this probably represents the presence of copper sulphide minerals at relatively shallow depths (50-100m).
• Parts of the system appear to contain chalcopyrite and pyrite in roughly equal portions, making the IP highs very attractive targets for copper-sulphide mineralisation
• The eastern IP high coincides with a well-defined 600x200 zone of partially exposed mineralisation. Soil samples average 1380ppm Cu and 180ppb Au.
• The western IP high is larger and stronger and is hidden beneath transported material. A more subtle geochemical anomaly contains soil samples with up to 600ppm Cu and 77ppb Au.
• Primary sulphide (chalcopyrite) and secondary (cuprite and covellite) copper minerals have been identified in some rock samples, however, in the majority of samples the sulphide minerals are completely oxidised. Copper will have been leached from the oxidised rocks.
• The reprocessed IP data together with geochemical and geological data allow for definition of several high-priority drill targets
• Drill permitting is underway
Page 1 of 6
Australian exploration company, Global Geoscience Ltd ("Global") (ASX: GSC), today announced it has identified a very promising copper-gold target on the Quillcata prospect within the Company's 100%-owned Mancha Pampa discovery in Peru.
The upgrade of the Quillcata Cu-Au target follows reprocessing of Induced Polarisation (IP) geophysical data. An IP chargeability high forms a large annular zone around a porphyry intrusion and correlates well with surficial copper, gold and silver mineralisation (Figures 1 and 2).
Surface outcrops above the IP high are oxidised and contain high levels of copper and gold (up to
2.5% Cu and 4g/t Au) together with Ag-As-Bi-Mo. The surface mineralisation at Quillcata suggests that the IP high probably represents the presence of copper sulphide minerals at relatively shallow depths (50-100m).
The target can be tested with a program of up to eight 250m deep diamond drill holes for a total of
2000m. Permitting for these holes is underway.
Location
The wholly-owned Mancha Pampa copper-gold project is located 150 km southeast of Lima in the district of Yauyos, central Peru. Access to the area is via the Pan American Highway followed by an all-weather road and tracks via the village of Huantan.
Mancha Pampa is located in the Andean belt of porphyry copper deposits extending from Chile, through Peru and into Ecuador. This region is responsible for a major portion of worldwide annual copper production.
Ownership
Global Geoscience owns 100% of the project through its subsidiary company, Paradigm Peru SAC. Granted mining permits cover an area of 14 sq km. The project is subject to a 2.5% NSR royalty payable to the founding shareholders of Global Geoscience.
Nearby Deposits
Sierra Metal's Yauricocha Ag-Pb-Zn-Cu mine is located approximately 30km to the north. Yauricocha is a carbonate replacement style deposit related to the nearby Yauricocha stock. Yauricocha has been in production since 1948 and since 1973 has produced 13.6Mt of ore at an average grade of 144g/t Ag, 2.8% Pb, 4.5% Zn and 0.8% Cu. Current Resources (Measured and Indicated) are 11.4Mt at 57g/t Ag, 0.85% Pb, 1.73% Zn, 0.83% Cu and 0.76g/t Au (Sierra Metals Inc, 2015).
Minera Chinalco's Toromocho porphyry Cu-Mo mine is located 110km to the northwest. The deposit has quoted Reserves (Proven and Probable) of 1.5Bt at 0.47% Cu, 190ppm Mo and 6.86g/t Ag (Chinalco Mining Corporation International, 2015). Global Geoscience has no economic interest in Yauricocha or Toromocho.
Geology
The oldest rocks in the Mancha Pampa project consist of moderately folded Mesozoic sediments. These are overlain by the relatively flat lying Tantara Formation of Paleocene age. This formation is in turn overlain by andesite flows, rhyolite and volcanoclastic rocks of the Sacsaquero Group. A number of igneous bodies intrude these rocks, including porphyry, rhyolite dykes and tonalite and granodiorite of the coastal batholith.
Page 2 of 6
The Quillcata prospect is hosted by andesite flows and rhyolitic volcanoclastic rocks of the Sacsaquero Group. A central porphyry intrusion is intensely altered and stockwork veined but largely devoid of sulphide minerals and anomalous metal concentrations. Alteration within the intrusion is primarily intense and of the Sodic-Calcic type (albite-quartz-diopside-actinolite).
Copper-gold mineralisation mainly occurs within the Potassic (K-feldspar-biotite-sulphides) alteration which forms an annular zone around the intrusive and Sodic-Calcic alteration. Phyllic (quartz-sericite) and Propylitic (albite-chlorite-sericite-calcite) alteration are sequentially developed peripheral to Potassic alteration.
The zone of strongest Cu-Au mineralisation is highly fractured and oxidised. Based on limited, discontinuous exposure, original sulphide contents are estimated at between 2 to 15% total sulphide minerals in veinlets and disseminations. Pyrite and chalcopyrite appear to occur in roughly equal proportions.
Geochemistry
Soil and rock chip geochemical samples are anomalous in copper, molybdenum, gold, silver, bismuth and arsenic. They define an 800m x 1000m discontinuous zone of anomalous metal concentration (Figure 2).
Within this broader zone and on the eastern margin of the intrusion, a 600m x 200m continuous zone is strongly anomalous in Cu-Au-Ag-As-Bi-Mo. Soils average 1380ppm Cu, 180ppb Au,
6ppm Ag, 73ppm Bi, 11ppm Mo and rocks contain up to 2.5% Cu, 4ppm Au, 67g/t Ag, 303ppm Bi,
157ppm Mo. This zone corresponds to an area of potassic alteration and to the eastern IP chargeability high (Figure 2b, 2d). The strongest gold-soil values (>80ppb) correlate with a NNW trending zone of magnetic low (Figure 2c).
Elsewhere within the broad zone of anomalous geochemistry values are more varied. This is probably a function of the distribution and thickness of cover. On the western margin of the intrusion and coincidental with the western IP chargeability high, soil samples contain up to
600ppm Cu, 77ppb Au, 2.4ppm Ag, 73ppm Bi, 24ppm Mo and rock samples up to 2.9ppm Au,
70ppm Bi, 19ppm Mo. This area is almost entirely hidden under a thin layer of transported cover.
The composition, geometry and zoning of mineralisation and accompanying style of alteration are consistent with the deeper parts of a copper-gold porphyry system.
Geophysics
Induced polarisation (IP), magnetic and radiometric surveys were completed by Global Geoscience in 2010 (Figure 2). The IP survey identified a zone of high chargeability coincidental with the strongest geochemistry; however, the absolute values were, at the time, considered relatively low for a porphyry system. It was recognized that a possible explanation for this is the abundance of
chalcopyrite relative to pyrite - something that had been observed in oxidized rocks at Quillcata and a common characteristic of the deeper parts of porphyry systems. Chalcopyrite is less chargeable than pyrite and will give rise to a weaker chargeability high.
Recent reprocessing of the geophysical data determined that previous processing underestimated the amplitude of the IP chargeability highs. Two chargeability highs of interest have now been
identified (Figure 1). A smaller eastern IP high that coincides with the strongest Cu-Au mineralisation and potassic alteration and a larger, stronger western IP high that is largely covered by transported material. Chargeability values are up to 20mv/volt and may be reflecting
Page 3 of 6
chalcopyrite-rich mineralization as has been observed at surface in oxidized outcrops. The western
IP high coincides with a resistivity low which may indicate alteration.
The central intrusion is a very distinct zone of radiometric potassium low (K-low) explained by the strong quartz-albite alteration and lack of potassic alteration minerals such as K-feldspar and biotite (Figure 2d). An arcuate zone of radiometric potassium high (K-high) occurs to the east of the intrusion and is coincidental with the IP chargeability high and Cu-Au mineralisation. The K-high
is explained by secondary K-feldspar and biotite (part of the potassic alteration zone) that have been identified and mapped in outcrop.
About Global Geoscience
Global Geoscience is a Sydney-based mineral exploration company specialising in greenfield
exploration and mineral discovery. The Company's main focus is for copper, gold and silver on its mostly 100%-owned projects in Nevada and Arizona in the United States, and Peru in South America.
References
Global Geoscience Ltd company announcements:
|
Date
|
Title
|
|
21/06/2010
|
Geophysical survey underway at Mancha Pampa project in Peru
|
Sierra Metals Incorporated, 2015. Yauricocha Mine, company website.
Chinalco Mining Corporation International, 2015. Project Toromocho, company website.
MEDIA CONTACT:
Bernard Rowe John Field
Managing Director Field Public Relations
Global Geoscience Ltd (08) 8234 9555 (02) 9922 5800 0418 819 527
04 1944 7280
The information in this report that relates to Exploration Results is based on information compiled by Peter Nicholson, a Competent Person who is a Fellow of The Australasian Institute of Mining and Metallurgy. Peter Nicholson is employed by Nicholson Geologist Pty Ltd and acts as a consultant to the company. Peter Nicholson is Technical Director of Global Geoscience Ltd and owns shares and options in the company.
Peter Nicholson has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken 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'. Peter Nicholson consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.
Page 4 of 6
Western chargeability high Hidden under thin cover Subtle Cu-Au-As-Bi-Mo
Eastern chargeability high
Cu-Au mineralisation at surface
Strong Cu-Au-Ag-As-Bi Mo
Rocks to 2.5% Cu, 4g/t Au, 67g/t Ag
Potassic alteration
Proposed drill traverse
Porphyry
UTM Zone 18S PSAD56
Figure 1. Quillacata Prospect at Mancha Pampa. IP chargeability colour grid (50m depth) showing lines of proposed drilling. IP chargeability highs coincide with copper mineralisation at surface and are probably caused by chalcopyrite and pyrite at depth. The larger, western IP high is hidden under thin cover.
Page 5 of 6
2a. Google Image
2b. IP Chargeability
2c. Magnetics -TMI RTP
2d. K-Radiometrics
Figure 2. Quillacata Prospect at Mancha Pampa. Geophysical images showing copper, gold and bismuth soil geochemistry. Copper coincides with IP chargeability (2b) and potassic (K) highs (2d), gold coincides with a NNW-trending magnetic low (2c) and the central porphyry intrusion is a strong and distinct potassium low (2d).
Page 6 of 6
Appendix 1 - Mancha Pampa Cu-Au Project, Peru
JORC Code, 2012 Edition - Table 1
Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
Criteria JORC Code explanation Commentary
Sampling techniques
Drilling techniques
Drill sample recovery
• Nature and quality of sampling (eg cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling.
• Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used.
• Aspects of the determination of mineralisation that are Material to the
Public Report.
• In cases where 'industry standard' work has been done this would be relatively simple (eg 'reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay'). In other cases more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (eg submarine nodules) may warrant disclosure of detailed information.
• Drill type (eg core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or standard tube, depth of diamond tails, face-sampling bit or other type, whether core is oriented and if so, by what method, etc).
• Method of recording and assessing core and chip sample recoveries and results assessed.
• Measures taken to maximise sample recovery and ensure representative nature of the samples.
• Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material.
• Soil and rock chip sampling has been undertaken in several phases
• Some of these results were prepared and first disclosed under the JORC Code 2004 and are being updated herein to comply with JORC Code 2012
• Soil samples of approximately 1kg were collected from accumulations of fine material at surface. Due to the steep topography some of the material sampled will have moved down slope to varying degrees.
• Rock chip samples of approximately 2-5kg were collected from outcrop as random grab samples and semi-continuous channel samples.
• Samples were collected, bagged and given a unique number on site.
• Entire samples were submitted to ALS Chemex in Lima or Arequipa, Peru for preparation and analysis.
• Industry standard methods were used for the collection, preparation and analysis of the samples.
• Not applicable as no drill results are being reported.
• Not applicable as no drill results are being reported.
Logging • Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate
• Not applicable as no drill results are being reported.
1
Criteria JORC Code explanation Commentary
Mineral Resource estimation, mining studies and metallurgical studies.
• Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc) photography.
• The total length and percentage of the relevant intersections logged.
Sub-sampling techniques and sample preparation
Quality of assay data and laboratory tests
Verification of sampling and assaying
Location of data points
• If core, whether cut or sawn and whether quarter, half or all core taken.
• If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry.
• For all sample types, the nature, quality and appropriateness of the sample preparation technique.
• Quality control procedures adopted for all sub-sampling stages to maximise representivity of samples.
• Measures taken to ensure that the sampling is representative of the in situ material collected, including for instance results for field duplicate/second-half sampling.
• Whether sample sizes are appropriate to the grain size of the material being sampled.
• The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total.
• For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc.
• Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established.
• The verification of significant intersections by either independent or alternative company personnel.
• The use of twinned holes.
• Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols.
• Discuss any adjustment to assay data.
• Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation.
• No sub-sampling was undertaken.
• No duplicate or splitting of samples was deemed necessary for the type of samples collected.
• Rock grab samples were collected from outcrop over an area of ten square metres where possible.
• Based on previous exploration in the region for this style of mineralization, the sample size is appropriate.
• Samples were submitted to ALS Chemex in Lima and Arequipa, Peru
• Soil samples were dried and pulverized (entire sample).
• Rock samples were dried, crushed, split (riffle) and a 1kg sub-sample was then pulverized.
• Soil samples were analyzed for gold by fire assay and ICP-AES (50g)
• Soil samples were analyzed for other elements by 4-acid ICPAES
• Rock samples were analyzed for gold by fire assay and AAS (50g)
• Rock samples were analyzed for other elements by four-acid ICPAES
• The methods are considered to give a total content reading.
• Standard, blank and duplicate samples were randomly inserted into the sample stream. Acceptable levels of accuracy were achieved.
• Not applicable as no drill intersections are being reported.
• Electronic data was obtained directly from ALS and entered into MS Access database. Lab data was matched to field data (including location) by the unique sample number.
• No adjustments were made to the assay data.
• The sample sites were located using a hand-held GPS unit with an accuracy of +/- 5 metres.
2
Criteria JORC Code explanation Commentary
Data spacing and distribution
Orientation of data in relation to geological structure
• Specification of the grid system used.
• Quality and adequacy of topographic control.
• Data spacing for reporting of Exploration Results.
• Whether the data spacing and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied.
• Whether sample compositing has been applied.
• Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type.
• If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material.
• All coordinates are shown in UTM Zone 18S (PSAD56).
• The samples were plotted on a topographic base with 10m elevation accuracy.
• Soil samples were collected along lines at 10m to 50m spacing.
• Soil lines were spaced 100m to 200m apart.
• Rock chip samples were collected from in-situ outcrop as either random grab samples or channel samples.
• Rock chip channel samples were collected as a continuous, 4m long sub-horizontal channel wherever possible.
• These data cannot be used for estimation procedures.
• Soil and rock samples were collected along lines oriented to achieve unbiased coverage based on outcrop mapping.
• Due to steep topography, some of material sampled will have moved down slope to varying degrees. This does not affect the overall interpretation of the results.
Sample security
Audits or reviews
• The measures taken to ensure sample security. • Samples were collected, bagged and numbered on site by experienced company personnel and promptly submitted to ALS Chemex. Security measures were appropriate for the type of samples.
• The results of any audits or reviews of sampling techniques and data. • No audits or reviews were undertaken and are not deemed necessary for the type of sampling being reported and the early-stage nature of the exploration work being undertaken.
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Criteria JORC Code explanation Commentary
Mineral tenement and land tenure status
• Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings.
• The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area.
• 100% ownership of two mining concessions (Quillcata 1 and Quillcata
2) covering an area of 14 square kilometers.
• The concessions are located on land owned by the local community with whom Global Geoscience has an access agreement.
• The project is subject to a 2.5% NSR royalty payable to the founding shareholders of Global Geoscience.
• There are no known impediments to exploration or mining in the area.
3
Criteria JORC Code explanation Commentary
Exploration done by other parties
• Acknowledgment and appraisal of exploration by other parties. • There is no known previous exploration or any evidence thereof.
Geology • Deposit type, geological setting and style of mineralisation. • Porphyry copper-gold deposit type.
• Located in the porphyry copper belt of Peru.
• Copper and gold mineralization related to a porphyry intrusion.
Drill hole
Information
Data aggregation methods
Relationship between mineralisation widths and intercept lengths
• A summary of all information material to the understanding of the exploration results including a tabulation of the following information for all Material drill holes:
o easting and northing of the drill hole collar
o elevation or RL (Reduced Level - elevation above sea level in
metres) of the drill hole collar
o dip and azimuth of the hole
o down hole length and interception depth
o hole length.
• If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from
the understanding of the report, the Competent Person should clearly
explain why this is the case.
• In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (eg cutting of high grades) and cut-off grades are usually Material and should be stated.
• Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail.
• The assumptions used for any reporting of metal equivalent values should be clearly stated.
• These relationships are particularly important in the reporting of
Exploration Results.
• If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported.
• If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (eg 'down hole length, true width not known').
• Not applicable as no drill results are being reported.
• Not applicable as no data aggregation methods have been used.
• Not applicable as the results being reported do not relate to widths or intercept lengths of mineralisation.
Diagrams • Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported These should include, but not be limited to a plan view of
• A summary map is included in the report showing the location of the surface copper anomaly relative to the porphyry intrusion and IP chargeability highs.
4
Criteria JORC Code explanation Commentary
drill hole collar locations and appropriate sectional views. • The map includes a scale and location information.
Balanced reporting
Other substantive exploration data
• Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced to avoid misleading reporting of Exploration Results.
• Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples - size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances.
• The results reported are considered representative.
• Soil and rock geochemical results are not indicative of grade but do provide an indication of the presence of mineralisation.
• Ground geophysical surveys were conducted in 2010 and the data reprocessed in June 2015.
• Surveys were conducted by Arce Geofisicos of Lima, Peru and comprised pole-pole induced polarisation, magnetic, radiometric and self-potential.
• Survey lines were oriented east-west and spaced at 200m
• Readings were collected at 10m (magnetic and radiometric) and 50m
(induced polarisation) intervals along the lines
• Location was by DGPS with sub-metre accuracy
Further work • The nature and scale of planned further work (eg tests for lateral extensions or depth extensions or large-scale step-out drilling).
• Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive.
• Further work is likely to include core drilling to test the Cu-Au geochemical anomalies and the IP chargeability highs.
• Proposed drill traverses are shown on Figure 1.
• A drilling permit is required before drilling can commence
5