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Providing expert advice to theCanahuire project in southern PeruIDioriteLocation of the Pogo Liese, East Deep, and 4021gold zones relative to the post-mineralisationdiorite and late sinistral faultthe lateral continuation of the Liesevein system beyond the diorite and willrepresent a significant contribution to theresource inventory of the Pogo deposit.Sumitomo is currently planning a newportal and decline ramp from the surfacethat will link in with two exploration driftsthat have been driven over to this zone.In addition, a significant outcome forSumitomo’s collaboration with SRKwas the ability to start 4-dimensionalreconstructions. A great exampleof this was the realisation that theLiese Creek diorite existed north ofthe 4021 prospect (figure above).In addition, when overlain with theinterpreted structural events, thisoffset is seen to be from a northeasttrending sinistral fault. By reconstructingthis movement, Sumitomo will havea better understanding of targetinggold mineralisation between the Lieseand 4021 zones. This has led to theconstruction of an updated “Liese Zone”model of gold mineralisation.n August 2010, Canteras Del HallazgoS.A.C., (CDH) a joint venture betweenGold Fields Ltd. and Companiade Minas Buenaventura S.A.A.,commissioned SRK Consulting Canadato provide expert structural geologyadvice into the exploration andresource delineation programs at theCanahuire Project in southern Peru.This assignment included reviewingand providing recommendations forincreasing the understanding of thestructural geology of the Canahuiredeposit through staged reviews andinput (two site visits and one datareview meeting) over the course ofone year. SRK worked closely withthe CDH and Gold Fields explorationteams, in part providing on-the-jobtraining to key project personnel asthe study progressed.The Canahuire deposit is anintermediate sulfidation epithermalgold-copper-silver deposit hostedwithin breccias of a diatreme complexthat crosscuts deformed Yura Groupsedimentary rocks. The deposit islocated 120 km northeast of the cityof Moquegua, in the Ichuna regionof the Andean fold and thrust belt ofsouthern Peru. This area of Peru hasrecently received renewed explorationinterest, including the discovery of theCanahuire deposit, in part related toa regional prospectivity analysis thatSRK previously conducted.SRK provided a definition of theregional tectonic history, includingthe tectonic controls on the formationof the Canahuire deposit and howthese may be related to otherporphyry and epithermal districts insouthern Peru. This regional analysisoutlined potential structural trendsand locations that are important forexploration in the Ichuna region on abroader scale.The Canahuire deposit displays astrong structural and geometricalcontrol to the distribution of diatremefacies and also gold-copper-silvermineralisation. A particular focus ofSRK’s input and analysis was on thecontrols on the distribution of highergrade ( 10 grams per tonne) gold.This included outlining the potentialgeometry of hydrothermal pathwaysand traps, and the influence ofpost-mineralisation faulting on themodification of grade distributionwithin the deposit.James Siddorn: jsiddorn@srk.comJames Siddorn at 5000m elevation with the Canahuire deposit (orange-brown oxide weathering) in the distanceJames Siddorn: jsiddorn@srk.com5

Ground based geophysicsMore and more, geophysics isbecoming an important explorationtool as companies turn their effortstowards hidden and buried deposits.However, it is vital to know thelimitations of both the techniques anddata when designing, implementingand interpreting the results of ageophysical program. One aspect ofthis fact was highlighted in a recentSRK ES project involving inducedpolarisation (IP) and time-domainelectromagnetic (TEM) surveys inOman, in search of copper-goldmineralisation for Gentor Resources.Following a site visit to audit drillingprotocols and logging procedures,SRK ES was commissioned toconduct followup ground geophysicsover a pre-defined airborneelectromagnetic anomaly in theOman Mountains, west of Sohar.While a gravity survey to assist in theexploration was initially requested,having seen the very rugged terrainin the prospect areas firsthand, SRKES considered this impractical. Itwould require a highly accurate digitalelevation model to correct the data.That work exceeded the needs of theproject at its current stage and wouldadd limited geological value, given thetime it would take to complete.As an alternative, SRK ES conductedan IP and TEM survey over a threeweek period, which involved verychallenging fieldwork in rough terrain.The process of data collection had tobe adapted to the ground conditions,as they proved problematic whentrying to obtain good electricalcontacts for the IP survey. The TEMsurvey progressed rapidly, producingresults that improved the definition ofthe conductive anomaly and coincidedwell with mineralised intersectionsin previous diamond core drill holes.Due to the speed at which SRK EScompleted these survey lines, twofurther prospect areas were coveredwith TEM surveys.The results left Gentor with a numberof promising targets to follow up withfurther studies and scout drilling. Incontracting SRK ES, Gentor gainedrobust geophysical results in atimely manner, despite the obstaclespresented by steep scree slopes andexposed environments.Dan Marsh: dmarsh@srkexploration.comExample surfaces modelled in Leapfrog,representing fault surfaces as logged incore at the Youga Gold Mine, Burkina Faso.The image reproduced with permission ofEndeavour Mining Corporation.An understanding of the structuralcontrols on zones of mineralisationis of fundamental importance forbrownfield exploration efforts.The combination of field geologyobservational skills with new, rapid,computerised modelling toolsenhances SRK’s ability to providerapid three-dimensional answers toclients. SRK’s Vancouver office hasbeen fairly active in gold projects inBurkina Faso, including the Tanloukaproject on the Markoye shear zonein the central-east of the country,the Youga deposits in the southeastand the Nami gold zone of the Karmadeposit in the Goyen greenstone beltin the western part of the country.In Burkina Faso, SRK is typicallytasked to explain the timing of thepossible gold mineralising eventsrelative to the PaleoproterozoicEburnean deformational history, andto define the controlling structuralgeometries on the mineralisation.Time-domain electromagnetic (TEM) surveying for Au/Cu mineralisation in Oman6

Rapid assessment of structural geometriesfor brownfield targeting, Burkina FasoWay n e bar n e t tWayne Barnett has14 years’ experiencein the mining andexploration industry.He is a specialistin structuralgeological analysisand 3D modellingfor rock masscharacterisation and geotechnical riskevaluation. Wayne consults in structuraland geotechnical drill core logging andquality management, mapping datacapture, in rock joint characterisationand the spatial domain-based analysis ofstructural and geotechnical data.Wayne Barnett: wbarnett@srk.comMineralisation often occurs earlyrelative to deformation, and goldmay be deposited or mobilised morethan once. Fundamental structuralobservations of deformation timingis key to determining the possiblelarge- and small-scale geometries ofmineralisation. Available data variesbetween projects, but may be derivedfrom mapping and/or drill core. Rapidvisualisation of zones of mineralisationand rapid modelling is very valuablebefore, during and after the site visit,during the post-visit interpretation(see figure above).We typically use software to evaluatethe distribution of mineralisationintersected in existing drill holesbefore the site visit, in order toselect the key drill holes that requireobservation, based on preliminaryinterpretation. During the site visit,drill core observations of structuraldeformation textures, cross-cuttingrelationships, as well as orientatedcore measurements of structuralgeometries are used to test andcontinue the interpretation of themineralisation timing and geometry.The observations are immediatelyintegrated back into 3D tocontinuously develop and test the3D models. Leapfrog’s AranzTM(ARANZ Geo Limited) acceleratedwireframing capability allowsgeologists to demonstrate to theclient a 3D structural interpretationand a tangible product even beforethe site visit ends. Preliminaryideas on further drill targeting canbe presented and debated with theproject geologists.The integration of structuralobservational skills and new advanced3D modelling tools is a successfulcombination that improves SRK’sability to add value to our clients inbrownfields exploration.Wayne Barnett: wbarnett@srk.com7Dan MarshDan Marsh is anExplorationGeologist with SRKES specialisingin explorationgeophysics. Danholds a Master’sdegree in Geophysicsfrom the Universityof Southampton and has three years’experience in exploration geophysics,first with Rio Tinto and now with SRKES. Dan is part of a geophysical teamthat designs and reviews investigations,including ground magnetic, inducedpolarisation (IP), time domainelectromagnetic (TEM) and radiometricsurveys for a range of commodities with aglobal reach.Dan Marsh: dmarsh@srkexploration.com

Target generation and grassrootsexploration in MauritaniaNiall TomlinsonNiall Tomlinson(MSc CGeol), isan ExplorationGeologist andnow an Associatewith SRK ES. Hehas extensivefield experiencein South America,West Africa and Central Asia. Hisexpertise covers the managementand implementation of integratedexploration programs at variousstages, from grassroots to feasibility,and in a variety of commodities.Exploration camp in southern Mauritanides, MauritaniaGareth O’DonovanGareth O’Donovanis a CorporateConsultant(Exploration) with over26 years experiencein mining andexploration projectsin Africa, SouthAmerica, the RussianFederation and Asia. He specialises in thedesign, implementation and managementof exploration projects from grassrootsto pre-feasibility in all terrains andenvironments, mobilising multi-disciplinaryfield teams. More recently, Gareth hasconcentrated on reviews, competentperson’s reports, audits and valuationsof exploration and mining propertiesworldwide and in a variety of commodities.For the past 9 years he has been ManagingDirector of SRK Exploration Services Ltdbased in Cardiff.Gareth O’Donovan:godonovan@srkexploration.comIn 2010/11 SRK Exploration Serviceswas commissioned by Alecto Energyplc to conduct its grassroots copper/gold exploration program in SouthernMauritania. From the outset, SRK’sinvolvement started with visits andmeetings with the MauritanianMinistry of Mines on Alecto’s behalf.This culminated in selecting threelicences in the Mauritanian MobileBelt, followed by reconnaissance visitsto the licence locations in August2010, during which we observed areasof copper oxide mineralisation at thesurface. A rock chip sampling programreturned anomalous copper values,generating a number of targets forfollow-up exploration.Following fund raising based onthese results, SRK ES designed amulti-phase exploration program togenerate exploration targets and makea decision on the merit of each licence.Work began with a soil samplingprogram over targets generated in8the reconnaissance phase. SRK ESmobilised an experienced team toa remote location on the fringe ofthe Sahara to manage the significantlogistical requirement, and conduct thesampling program and other activities,such as detailed geological mapping.SRK ES used a mobile XRF analyserto test samples in the field, therebyallowing for rapid identification ofany significant mineralisation and theimmediate design of any requiredinfill sampling. This process resultedin a cost saving to the client fromreduced laboratory costs and increasedefficiency of sampling. All samplesgenerated with anomalous coppervalues and/or gold pathfinder elementswere also submitted for laboratorytesting to confirm their content.We are now planning the next phasefor these prospects by assistingAlecto in rapidly advancing theirexploration assets towards a drilling

Evolution of SRK ESSRKExploration Services Ltd(SRK ES) was established in Cardiffin 2003 as a small group of likeminded exploration geologists with aview to filling a perceived gap in theconsultancy market. Initially formed as asubsidiary company of SRK ConsultingUK, SRK ES achieved full SRKConsulting Practice status in 2008.Headed by the Managing Director GarethO’Donovan, the initial staff comprised ofa small number of permanent associates,all of whom believed in the SRK ESphilosophy that everything is possible.Over the years the team has expandedto more than 20 permanent staffplus a large team of associates andcontractors worldwide. Our philosophyremains “yes, we can do that”.stage. This phase involves groundgeophysics and trenching of thetargets previously identified; both willbe managed by the SRK ES in-housegeophysical and geological teams.SRK ES aims to help Alecto establisheffective field teams and camps andmanage the project’s developmentthrough office-based consultingservices, as well as ground teams andgeological supervision.By contracting SRK ES to managetheir exploration portfolio, Alectowas able to engage an experiencedand integrated multi-disciplinaryexploration team on the ground,developing targets in a time andcost effective manner, while givingpotential investors confidence in themanagement of the program.In an increasingly competitive marketSRK ES has built a strong team ofexploration-focused geologists whoare young and enthusiastic, individuallyskilled but also backed by a wide rangeof experienced experts in their field.Our Principal Group includes JamesGilbertson, Bill Kellaway, AlexandraAkyurek, Tracey Laight and MikhailTsypukov. Their experience base isextensive, covering exploration, programdesign, management and review, projectvaluation, geological modelling, and inputto corporate mergers and acquisitions.To ensure that the younger explorationgeologists joining the team benefitfrom the broad experience of theircolleagues, SRK ES has developed anin-house training program designedto share experiences and establish abase level of skills that normally requiredecades to gain.SRK ES continues to provide traditionalconsultancy services, technical reviews,valuations, and competent person’sreports as well as hands-on explorationmanagement, offering a wide range ofexploration skills in various commoditiesand terrains. Our newest branch office,SRK ES Denmark, headed by CasperMejer Petersen, was opened in 2012 tosupport the growing exploration industryin Greenland.We particularly endeavor to provideassistance to early stage explorationentrepreneurs and junior explorationcompanies who have ideas butinsufficient technical skills to executethe exploration work required. SRK ESprovides a package to these companiesthat includes access to a large team ofskilled individuals for a limited periodof time, sufficient to execute a fieldprogram without having to search forand hire its own staff.Our services range across targetgeneration, licence acquisition,program design and execution, andwe provide an important interface withthe upstream departments of the SRKConsulting Group and their resourceand mining expertise.Gareth O’Donovan:godonovan@srkexploration.comNiall TomlinsonGareth O’Donovan:godonovan@srk.exploration.comPart of the Gardar Province, South Greenland. Home to some of the world’s largest REE and Ta-Nb deposits9

Applying conceptual geometricalmodels in evaluating mineral prospectsContinuity of geology and grade arekey traits that must be demonstrableduring the process of estimating areportable Mineral Resource. Toooften, however, assay grade takesprecedence in interpreting the socalled geological model, while thegeology – lithology, structure andalteration – are vastly underused oreven ignored during the modellingprocess. This can lead to a follow-thedots (grade) geological model in whichlittle or no thought has been devotedto the actual likelihood of the gradesbeing linked according to the model.Over the years, SRK has encounterednumerous projects where seeminglysimple geological models, based ongrade alone, have become unstuck ata later phase of exploration, evaluationor production. By paying carefulattention to the geological structuresin drillholes and by applying a relevantempirical geometrical relationship orconceptual geometrical model to thegeology of the deposit, the geologistcan produce a more accurate reflectionof the geology in the 3D models usedin Mineral Resource Estimates.Because SRK’s Structural Geologistsare highly qualified and have conductedtechnical evaluations on many deposittypes, their experience allows themto draw on conceptual models ofDot-to-dotthe geometry or controls on mineraldeposits and a case book of real-worldexamples. This breadth of experienceis particularly useful in the explorationstage, where geometrical informationis scarce.Juno1 (left): Geological block model showing fold axis,faults, assays and ore shoot. Juno2 (right): Sectionsand plan showing different prospectivity within thegeological block model.Knowledge and project experiencebring a sound footing for the accurateinterpretation of geological data andthe means to interpret the continuityof mineralised veins and dykes, foldedgeological bodies and stratiformdeposits with increased confidence,lowering the overall project risk.Recent examples have included: the interpretation of complex veinfault relationships in an epithermalAu-Ag deposit to explain the variableexploration intercepts, and to assistin defining geological domains for theMineral Resource Estimate. using conceptual models of veingeometry and growth to assist in thecharacterisation and likely impactson mining of a significant gemstonedeposit. identifying pre-lithificationdeformation in sediments fromdrillholes and reinterpreting drillsections in a large, early-stage bulkcommodity exploration.Chris Bonson: cbonson@srk.co.ukReality!Schematic diagram of how a dot-to-dot approach can get it wrong, with grave consequences.Recognition at the early stages can mitigate the risk to the project even in highly complex deposits.10Brownfield exploration poses manychallenges to the geologist: largeamounts of data are usually availablebut often difficult to integrate anduse effectively; at the same time oldideas and exploration models oftenhamper new interpretations andthe development of new targets.Traditional interpretation involves a timeconsuming and subjective 2D sectionanalysis. In contrast, 3D targeting addsa new approach to the brownfieldexploration rebus.Excalibur Mining Ltd is currentlyexploring for gold in the Tennant Creekregion of Australia’s Northern Territory.The company’s main focus is theredevelopment of the Juno and NoblesNob gold deposit (2Moz of mined ore)and the discovery of new depositsin the vicinity of the historical mines.The area has more than 80 years ofprospecting and exploration history anda very large quantity of data is availableto guide exploration. SRK has appliedstate-of-the-art 3D targeting to identifynew exploration targets in the area.

Excalibur 3D targetingFa b i o Ve r g a r aFabio Vergara, MSc,Structural Geology,is a GeologyConsultant withSRK’s Perth office.He specialises in3D modelling andgeological mappingand has worked onprojects in Australia and West Africa.His expertise includes developing 3Dmodels using Leapfrog , GOCAD andGeomodeller , geological mapping ofstructurally complex terrain and GIStargeting studies. He has worked on gold,VMS

exploration success are key drivers for continued investment in the exploration industry. Exploration for mineral deposits - global trends No. 47 . advisors, SRK hosted a workshop in Jakarta to advance the understanding of . located 120km northeast of the city of Moquegua, in the Ichuna region of the Andean fold and thrust belt of