Exploration for Mineral Deposits – Global Trends

news Exploration Geology

Exploration for mineral deposits – global trends

No. 47 SRK Consulting’s International Newsletter

Standing on an undeveloped iron ore deposit, Pilbara, WA, with the Brockman Formation forming the Hamersley Ranges in the background

Measuring the effectiveness of geological exploration and looking for trends that will lead to improved exploration success are key drivers for continued investment in the exploration industry.

Expenditure on exploration in Australia, for example, This decreasing discovery rate is reflected in reached a peak in 2008, which reflects a massive Australia strongly focused on brownfields drilling, increase in exploration for iron ore resources and, with 63% of expenditure on those targets. to a lesser extent, coal resources. The correction While the latest trends show a slight increase after the global financial crisis in late 2008 resulted in greenfields exploration, the overall trend in a significant drop in 2009 – up to 42% globally, shows a continuing focus on areas with a higher most of which was recovered in non-ferrous mineral probability of success. exploration expenditures in 2010. With respect to greenfield exploration, the The Australian Bureau of Statistics report on industry is moving from a phase of discovery of current trends shows continuing strength, but the near-surface deposits to generating methods for return on expenditure on new deposits has been discovery of deposits at depth, either below an disappointing. Geoscience Australia identifies only unconformity or within a basement terrane, but one gold discovery, three base metal discoveries with no exposure at surface. and one molybdenum discovery from 2008-2010. …continued 1 Exploration for mineral deposits (continued)

Both areas present significant SRK remains at the forefront of providing exploration challenges if the cost high-quality support to exploration of discovery is to remain within companies active in both brownfields economic bounds. and greenfields exploration. Search for deep or buried deposits relies on exploration targeting from geophysical Peter Williams datasets or specialised geochemical datasets by applying quality structural geology to geological interpretation of Peter has over them. Geological analysis remains a key 40 years experience component of greenfields exploration in the minerals support, and detailed mapping and industry, including advanced visualisation of structural 18 years as a data applied to brownfields or resource consultant on a expansion projects can add significantly range of projects to success. Particularly in brownfields, from project reviews advances in 3D modelling significantly and audits and enhance the probability of success and public reporting, to structural studies capability in designing drill programs on both a regional and orebody scale. based on geophysical and structural He has conducted major interpretation targets. Applying new modelling and projects from aeromagnetic data for visualisation techniques is at the core of exploration targeting, and has worked this competency. in a range of geological terranes in Australia, West Africa, East Africa, This newsletter provides case studies Zimbabwe, Zambia, Democratic Republic where SRK has contributed significantly, ining and exploration in Indonesia of Congo, Indonesia, Papua New Guinea, delivering discovery efficiently and M present challenges that are technical, Vanuatu, Solomon Islands and Europe. improving exploration success in an exploration environment that is legal and social in nature. The country Peter Williams: [email protected] increasingly technically challenging. is currently developing regulations for its new mining law, so there is some Peter Williams: [email protected] uncertainty, albeit within a well-defined legal framework.

Indonesia provides numerous opportunities for exploration, and SRK *Mineral Exploration *Metres Drilled is currently involved in several major Seasonally adjusted and trend series Original series projects there, mainly concerned with preparing JORC resource statements on coal, gold, laterite nickel and $m copper deposits. This active tectonic Seasonally Adjusted 1000 New deposits 2000 Trend Existing deposits environment with volcanic arcs from 800 1500 the Cretaceaous to Recent periods 600 overlying Late Paleozoic to Mesozoic 1000 400 basement rocks, contain some world

500 class orebodies. 200

0 0 Asia Minerals Corporation recently Jun Jun Jun Jun Jun Jun Jun Jun Jun Jun 2003 2005 2007 2009 2011 2003 2005 2007 2009 2011 engaged SRK Indonesia to assess the potential of small manganese deposits in Nusa Tengara Timor (NTT) in West * Source: Australian Bureau of Statistics, September 2011 Timor to feed a proposed new, local processing facility to comply with the new mining law. This will require a resource of about 2.5 million tonnes.

2 Indonesia – exploration on the cusp of development

Typical bedded manganese deposit and artisanal extraction techniques, West Timor (above); Massive chert manganese breccia deposits, unconformity related, with local owners, West Timor (left)

The opportunity is significant; Developing exploration skills employed and where geometry is there are more than 50 known either known or can be reasonably In collaboration with geologists from manganese sites in NTT, where the inferred. The results from testing Asia Minerals Corporation and other ore is currently extracted by artisanal these techniques will guide future advisors, SRK hosted a workshop in mining techniques and exported as program development. Jakarta to advance the understanding of unprocessed product. manganese deposits and generate an SRK will continue its involvement The individual deposits are small, exploration program that would address through field reviews, regular spread across extensive areas. Several the physical and climatic aspects of exploration program audits, and economically-viable, near-surface NTT in West Timor and provide the assessment of exploration results. deposits are commonly pursued highest probability of success in Over a 2-day workshop, Asia Minerals concurrently to provide sufficient defining manganese deposits to about Corporation learned about the key tonnes for processing. The advantage 50m depth along strike from known data collection required to assess is that deposits are generally high- occurrences. current exploration areas and generate grade with low impurities. The workshop identified and mapped exploration models, adopted a The key to discovering and those occurrences, and prioritised methodology to assess the entire exploiting such deposit fields is in them for field inspection. The mapping eastern NTT region for exploration understanding the deposit genesis for program outlined criteria and methods potential, and an immediate program targeting, and following a disciplined to determine the characteristics of to assess its current development exploration methodology. In Timor, the the deposits and to help develop a licence for preliminary resource deposits are located in sedimentary genetic model for NTT manganese. It estimation. In the process, it rock deposited on the seafloor, identified remote sensing requirements, gained a committed team aware of subsequently displaced across geophysical methods, including the different components that an the region, with numerous thrust potential field and active electrical exploration program needed and faults and remnant mud volcanoes. methods, and geochemical methods. the inter-relationships that deliver Currently, there is no model of The group defined a test area currently exploration success. seafloor manganese deposits that fits accessible under exploration licence, Peter Williams: [email protected] well with the Timor occurrences. where these techniques can be

3 Structural geology collaboration results in new find for Sumitomo

East Deep

Liese Zone

James Siddorn

James Siddorn, P.Geo., is a Practice Leader in Structural 4021 Geology, based in SRK’s Toronto office. He is a specialist in the structural In March 2010, Sumitomo Metal Gold mineralisation at Pogo is hosted analysis of ore Mining Pogo LLC (Sumitomo) within the structurally controlled Liese deposits, focused on commissioned SRK Consulting Canada vein system. Overall, the Liese vein deciphering the deposit-scale controls to undertake a structural geology system dips shallowly northwest and is a on ore plunge, geotechnical domains, interpretation of the Pogo district stacked system of three laminated veins and hydrogeological pathways. James in central Alaska, to assist ongoing (L1, L2, and L3). SRK and Sumitomo is an expert in the applied geological exploration targeting. The interpretation recognised that the lateral extent of interpretation of aeromagnetic data, was focused on compiling a structural the Liese vein system is large, with with extensive underground and geology interpretation of recently the L1 vein currently known to have a surface mapping experience, and broad acquired geophysical data, combined down-dip extent of greater than 1700 mining experience in conventional and with staged site visits, to examine the metres. The northeast margin of the mechanised underground mining. He structural geology of the Pogo deposit Liese vein system is truncated by a post- has spent 17 years in the structural and collaborate with the Sumitomo mineralisation diorite (about 95 million analysis and 3D geological modelling of exploration team. years old). The crosscutting nature of the gold, magmatic sulfide, silver, uranium, diorite, combined with the lateral extent The Pogo deposit is Alaska’s largest tantalum, and diamond deposits of the vein system, indicated to SRK and producing gold mine. It is underlain covering different geological terranes Sumitomo that the vein system may by high-grade gneisses of the Late worldwide. James has taught more than extend beyond the northeast margin of Proterozoic to mid-Paleozoic Yukon- 20 Applied Structural Geology courses the diorite, representing a significant Tanana terrane, which have been worldwide, to over 1000 geologists, exploration target in the shadow of the intruded by granitoid bodies, mostly geophysicists, and engineers. existing mill. belonging to a voluminous mid- James Siddorn: [email protected] Cretaceous suite. The Yukon-Tanana In 2011, Sumitomo began underground terrane and Cretaceous intrusions and surface drilling examining the extend from west of Fairbanks through potential for vein systems northeast of the central Yukon, for a distance of over the diorite and have since outlined a 700 kilometres. significant new gold zone, the East Deep zone. The East Deep zone represents

4 Providing expert advice to the Canahuire project in southern Peru

In August 2010, Canteras Del Hallazgo interest, including the discovery of the S.A.C., (CDH) a joint venture between Canahuire deposit, in part related to Gold Fields Ltd. and Compania a regional prospectivity analysis that de Minas Buenaventura S.A.A., SRK previously conducted. commissioned SRK Consulting Canada SRK provided a definition of the to provide expert structural geology regional tectonic history, including advice into the exploration and the tectonic controls on the formation resource delineation programs at the of the Canahuire deposit and how Canahuire Project in southern Peru. these may be related to other This assignment included reviewing porphyry and epithermal districts in and providing recommendations for southern Peru. This regional analysis increasing the understanding of the outlined potential structural trends structural geology of the Canahuire and locations that are important for deposit through staged reviews and exploration in the Ichuna region on a input (two site visits and one data Diorite broader scale. review meeting) over the course of one year. SRK worked closely with The Canahuire deposit displays a the CDH and Gold Fields exploration strong structural and geometrical teams, in part providing on-the-job control to the distribution of diatreme training to key project personnel as facies and also gold-copper-silver the study progressed. mineralisation. A particular focus of SRK’s input and analysis was on the Location of the Pogo Liese, East Deep, and 4021 The Canahuire deposit is an controls on the distribution of higher gold zones relative to the post-mineralisation intermediate sulfidation epithermal diorite and late sinistral fault grade (>10 grams per tonne) gold. gold-copper-silver deposit hosted This included outlining the potential within breccias of a diatreme complex geometry of hydrothermal pathways that crosscuts deformed Yura Group and traps, and the influence of the lateral continuation of the Liese sedimentary rocks. The deposit is post-mineralisation faulting on the vein system beyond the diorite and will located 120km northeast of the city modification of grade distribution represent a significant contribution to the of Moquegua, in the Ichuna region within the deposit. resource inventory of the Pogo deposit. of the Andean fold and thrust belt of Sumitomo is currently planning a new southern Peru. This area of Peru has James Siddorn: [email protected] portal and decline ramp from the surface recently received renewed exploration that will link in with two exploration drifts that have been driven over to this zone.

In addition, a significant outcome for Sumitomo’s collaboration with SRK was the ability to start 4-dimensional reconstructions. A great example of this was the realisation that the Liese Creek diorite existed north of the 4021 prospect (figure above). In addition, when overlain with the interpreted structural events, this offset is seen to be from a northeast- trending sinistral fault. By reconstructing this movement, Sumitomo will have a better understanding of targeting gold mineralisation between the Liese and 4021 zones. This has led to the construction of an updated “Liese Zone” model of gold mineralisation. James Siddorn at 5000m elevation with the Canahuire deposit (orange-brown oxide weathering) in the distance James Siddorn: [email protected]

5 Ground based geophysics

More and more, geophysics is add limited geological value, given the becoming an important exploration time it would take to complete. tool as companies turn their efforts As an alternative, SRK ES conducted towards hidden and buried deposits. an IP and TEM survey over a three- However, it is vital to know the week period, which involved very limitations of both the techniques and challenging fieldwork in rough terrain. data when designing, implementing The process of data collection had to and interpreting the results of a be adapted to the ground conditions, geophysical program. One aspect of as they proved problematic when this fact was highlighted in a recent trying to obtain good electrical SRK ES project involving induced contacts for the IP survey. The TEM polarisation (IP) and time-domain survey progressed rapidly, producing electromagnetic (TEM) surveys in results that improved the definition of Oman, in search of copper-gold the conductive anomaly and coincided mineralisation for Gentor Resources. well with mineralised intersections Following a site visit to audit drilling in previous diamond core drill holes. protocols and logging procedures, Due to the speed at which SRK ES SRK ES was commissioned to completed these survey lines, two conduct followup ground geophysics further prospect areas were covered over a pre-defined airborne with TEM surveys. Example surfaces modelled in Leapfrog, electromagnetic anomaly in the The results left Gentor with a number representing fault surfaces as logged in Oman Mountains, west of Sohar. core at the Youga Gold Mine, Burkina Faso. of promising targets to follow up with While a gravity survey to assist in the The image reproduced with permission of further studies and scout drilling. In Endeavour Mining Corporation. exploration was initially requested, contracting SRK ES, Gentor gained having seen the very rugged terrain robust geophysical results in a in the prospect areas firsthand, SRK timely manner, despite the obstacles ES considered this impractical. It presented by steep scree slopes and would require a highly accurate digital exposed environments. elevation model to correct the data. An understanding of the structural controls on zones of mineralisation That work exceeded the needs of the Dan Marsh: [email protected] project at its current stage and would is of fundamental importance for brownfield exploration efforts. The combination of field geology observational skills with new, rapid, computerised modelling tools enhances SRK’s ability to provide rapid three-dimensional answers to clients. SRK’s Vancouver office has been fairly active in gold projects in Burkina Faso, including the Tanlouka project on the Markoye shear zone in the central-east of the country, the Youga deposits in the southeast and the Nami gold zone of the Karma deposit in the Goyen greenstone belt in the western part of the country.

In Burkina Faso, SRK is typically tasked to explain the timing of the possible gold mineralising events relative to the Paleoproterozoic Eburnean deformational history, and to define the controlling structural geometries on the mineralisation.

Time-domain electromagnetic (TEM) surveying for Au/Cu mineralisation in Oman

6 Rapid assessment of structural geometries for brownfield targeting, Burkina Faso

Wayne barnett

Wayne Barnett has 14 years’ experience in the mining and exploration industry. He is a specialist in structural geological analysis and 3D modelling for rock mass characterisation and geotechnical risk evaluation. Wayne consults in structural and geotechnical drill core logging and quality management, mapping data capture, in rock joint characterisation and the spatial domain-based analysis of structural and geotechnical data.

Wayne Barnett: [email protected] Mineralisation often occurs early core measurements of structural relative to deformation, and gold geometries are used to test and may be deposited or mobilised more continue the interpretation of the Dan Marsh than once. Fundamental structural mineralisation timing and geometry. observations of deformation timing The observations are immediately Dan Marsh is an is key to determining the possible integrated back into 3D to Exploration large- and small-scale geometries of continuously develop and test the Geologist with SRK mineralisation. Available data varies 3D models. Leapfrog’s AranzTM ES specialising between projects, but may be derived (ARANZ Geo Limited) accelerated in exploration from mapping and/or drill core. Rapid wireframing capability allows geophysics. Dan visualisation of zones of mineralisation geologists to demonstrate to the holds a Master’s and rapid modelling is very valuable client a 3D structural interpretation degree in Geophysics before, during and after the site visit, and a tangible product even before from the University during the post-visit interpretation the site visit ends. Preliminary of Southampton and has three years’ (see figure above). ideas on further drill targeting can experience in exploration geophysics, be presented and debated with the We typically use software to evaluate first with Rio Tinto and now with SRK project geologists. the distribution of mineralisation ES. Dan is part of a geophysical team that designs and reviews investigations, intersected in existing drill holes The integration of structural including ground magnetic, induced before the site visit, in order to observational skills and new advanced polarisation (IP), time domain select the key drill holes that require 3D modelling tools is a successful electromagnetic (TEM) and radiometric observation, based on preliminary combination that improves SRK’s surveys for a range of commodities with a interpretation. During the site visit, ability to add value to our clients in global reach. drill core observations of structural brownfields exploration. deformation textures, cross-cutting Dan Marsh: [email protected] relationships, as well as orientated Wayne Barnett: [email protected]

7 Target generation and grassroots exploration in Mauritania

Niall Tomlinson

Niall Tomlinson (MSc CGeol), is an Exploration Geologist and now an Associate with SRK ES. He has extensive field experience in South America, West Africa and Central Asia. His expertise covers the management and implementation of integrated exploration programs at various stages, from grassroots to feasibility, and in a variety of commodities.

Exploration camp in southern Mauritanides, Mauritania Gareth O’Donovan In 2010/11 SRK Exploration Services the reconnaissance phase. SRK ES Gareth O’Donovan was commissioned by Alecto Energy mobilised an experienced team to is a Corporate plc to conduct its grassroots copper/ a remote location on the fringe of Consultant gold exploration program in Southern the Sahara to manage the significant (Exploration) with over Mauritania. From the outset, SRK’s logistical requirement, and conduct the 26 years experience involvement started with visits and sampling program and other activities, in mining and meetings with the Mauritanian such as detailed geological mapping. exploration projects Ministry of Mines on Alecto’s behalf. SRK ES used a mobile XRF analyser in Africa, South This culminated in selecting three to test samples in the field, thereby America, the Russian licences in the Mauritanian Mobile allowing for rapid identification of Federation and Asia. He specialises in the Belt, followed by reconnaissance visits any significant mineralisation and the design, implementation and management to the licence locations in August immediate design of any required of exploration projects from grassroots 2010, during which we observed areas infill sampling. This process resulted to pre-feasibility in all terrains and of copper oxide mineralisation at the in a cost saving to the client from environments, mobilising multi-disciplinary surface. A rock chip sampling program reduced laboratory costs and increased field teams. More recently, Gareth has returned anomalous copper values, efficiency of sampling. All samples concentrated on reviews, competent generating a number of targets for generated with anomalous copper person’s reports, audits and valuations follow-up exploration. values and/or gold pathfinder elements of exploration and mining properties Following fund raising based on were also submitted for laboratory worldwide and in a variety of commodities. these results, SRK ES designed a testing to confirm their content. For the past 9 years he has been Managing multi-phase exploration program to Director of SRK Exploration Services Ltd We are now planning the next phase generate exploration targets and make based in Cardiff. for these prospects by assisting a decision on the merit of each licence. Alecto in rapidly advancing their Gareth O’Donovan: Work began with a soil sampling exploration assets towards a drilling [email protected] program over targets generated in

8 Evolution of SRK ES

SRK Exploration Services Ltd in-house training program designed (SRK ES) was established in Cardiff to share experiences and establish a in 2003 as a small group of like- base level of skills that normally require minded exploration geologists with a decades to gain. view to filling a perceived gap in the SRK ES continues to provide traditional consultancy market. Initially formed as a consultancy services, technical reviews, subsidiary company of SRK Consulting valuations, and competent person’s UK, SRK ES achieved full SRK reports as well as hands-on exploration Consulting Practice status in 2008. management, offering a wide range of Headed by the Managing Director Gareth exploration skills in various commodities O’Donovan, the initial staff comprised of and terrains. Our newest branch office, a small number of permanent associates, SRK ES Denmark, headed by Casper all of whom believed in the SRK ES Mejer Petersen, was opened in 2012 to philosophy that everything is possible. support the growing exploration industry Over the years the team has expanded in Greenland. to more than 20 permanent staff We particularly endeavor to provide plus a large team of associates and assistance to early stage exploration contractors worldwide. Our philosophy entrepreneurs and junior exploration remains “yes, we can do that”. companies who have ideas but In an increasingly competitive market insufficient technical skills to execute SRK ES has built a strong team of the exploration work required. SRK ES exploration-focused geologists who provides a package to these companies are young and enthusiastic, individually that includes access to a large team of skilled but also backed by a wide range skilled individuals for a limited period of experienced experts in their field. of time, sufficient to execute a field Our Principal Group includes James program without having to search for stage. This phase involves ground Gilbertson, Bill Kellaway, Alexandra and hire its own staff. geophysics and trenching of the Akyurek, Tracey Laight and Mikhail targets previously identified; both will Our services range across target Tsypukov. Their experience base is be managed by the SRK ES in-house generation, licence acquisition, extensive, covering exploration, program geophysical and geological teams. program design and execution, and design, management and review, project SRK ES aims to help Alecto establish we provide an important interface with valuation, geological modelling, and input effective field teams and camps and the upstream departments of the SRK to corporate mergers and acquisitions. manage the project’s development Consulting Group and their resource through office-based consulting To ensure that the younger exploration and mining expertise. services, as well as ground teams and geologists joining the team benefit Gareth O’Donovan: geological supervision. from the broad experience of their [email protected] colleagues, SRK ES has developed an By contracting SRK ES to manage their exploration portfolio, Alecto was able to engage an experienced and integrated multi-disciplinary exploration team on the ground, developing targets in a time and cost effective manner, while giving potential investors confidence in the management of the program.

Niall Tomlinson

Gareth O’Donovan: [email protected]

Part of the Gardar Province, South Greenland. Home to some of the world’s largest REE and Ta-Nb deposits

9 Applying conceptual geometrical models in evaluating mineral prospects

Continuity of geology and grade are the geometry or controls on mineral key traits that must be demonstrable deposits and a case book of real-world during the process of estimating a examples. This breadth of experience Juno1 (left): Geological block model showing fold axis, faults, assays and ore shoot. Juno2 (right): Sections reportable Mineral Resource. Too is particularly useful in the exploration and plan showing different prospectivity within the often, however, assay grade takes stage, where geometrical information geological block model. precedence in interpreting the so- is scarce. called geological model, while the Knowledge and project experience geology – lithology, structure and bring a sound footing for the accurate alteration – are vastly underused or interpretation of geological data and even ignored during the modelling the means to interpret the continuity process. This can lead to a follow-the- of mineralised veins and dykes, folded dots (grade) geological model in which geological bodies and stratiform little or no thought has been devoted deposits with increased confidence, to the actual likelihood of the grades lowering the overall project risk. being linked according to the model. Recent examples have included: Over the years, SRK has encountered numerous projects where seemingly • the interpretation of complex vein- simple geological models, based on fault relationships in an epithermal grade alone, have become unstuck at Au-Ag deposit to explain the variable a later phase of exploration, evaluation exploration intercepts, and to assist or production. By paying careful in defining geological domains for the attention to the geological structures Mineral Resource Estimate. in drillholes and by applying a relevant • using conceptual models of vein empirical geometrical relationship or geometry and growth to assist in the conceptual geometrical model to the characterisation and likely impacts geology of the deposit, the geologist Brownfield exploration poses many on mining of a significant gemstone can produce a more accurate reflection challenges to the geologist: large deposit. of the geology in the 3D models used amounts of data are usually available in Mineral Resource Estimates. • identifying pre-lithification but often difficult to integrate and deformation in sediments from use effectively; at the same time old Because SRK’s Structural Geologists drillholes and reinterpreting drill ideas and exploration models often are highly qualified and have conducted sections in a large, early-stage bulk hamper new interpretations and technical evaluations on many deposit commodity exploration. the development of new targets. types, their experience allows them Chris Bonson: [email protected] Traditional interpretation involves a time- to draw on conceptual models of consuming and subjective 2D section analysis. In contrast, 3D targeting adds a new approach to the brownfield exploration rebus.

Excalibur Mining Ltd is currently exploring for gold in the Tennant Creek region of Australia’s Northern Territory. The company’s main focus is the redevelopment of the Juno and Nobles Nob gold deposit (2Moz of mined ore) and the discovery of new deposits Dot-to-dot Reality! in the vicinity of the historical mines. The area has more than 80 years of prospecting and exploration history and a very large quantity of data is available Schematic diagram of how a dot-to-dot approach can get it wrong, with grave consequences. to guide exploration. SRK has applied Recognition at the early stages can mitigate the risk to the project even in highly complex deposits. state-of-the-art 3D targeting to identify new exploration targets in the area.

10 Excalibur 3D targeting Fabio Vergara

Fabio Vergara, MSc, Structural Geology, is a Geology Consultant with SRK’s Perth office. He specialises in 3D modelling and geological mapping and has worked on projects in Australia and West Africa. His expertise includes developing 3D models using Leapfrog™, GOCAD™ and Geomodeller™, geological mapping of structurally complex terrain and GIS targeting studies. He has worked on gold, VMS, iron ore and IOCG deposits from early exploration to the brownfield stage.

Fabio Vergara: [email protected]

3D targeting is a new technique that • A rigorous review of the mineralisation Chris Bonson uses all available geological information model improved the geological to build a 3D block model of the site of understanding of the deposits Chris Bonson, interest. The model is interrogated and Principal Consultant • A step-by-step analysis allowed a the most prospective volumes identified. (Structural Geology) critical assessment of the quality To minimise modelling times rapid 3D with SRK Cardiff. of the information available and the modelling software such as GOCAD™, His principal area identification of areas of improvement, Leapfrog™ and Geomodeller™ are used. of expertise is where additional or better data could characterising The Excalibur study started with a be collected. This new information and evaluating the brain-storming session to identify could possibly be integrated in a structural geology the characterising features of the revised 3D targeting model allowing of mineral deposits. Juno and Nobles Nob deposits and the definition of better targets In practice, Chris’ work involves the define a Mineral System model to be analysis of geological structures from used as the geological framework. SRK believes 3D targeting can be outcrop and exploration data to help All available geological information successfully applied as an advanced in targeting and delineating mineral was then integrated in the model, exploration tool when sufficient data are deposits; along with 3D modelling of including lithologies, assays, structures, available. The flexibility of this approach geological structures and evaluation of geophysics (magnetic, EM), mineralised allows its application to all deposit their geotechnical and hydrogeological trends, etc. The final 3D model included styles and geological contexts with a risk to various mining scenarios. Chris several million cells, each containing high potential for structurally complex has contributed to technical evaluations information for the nine geological areas. The geological understanding of mineral projects around the world at properties considered. required to perform the analysis helps improve the geological model itself and the grassroots to advanced exploration Three main results were achieved: ensure that all targets identified have stage, through scoping and feasibility strong geological support. studies, to producing mines. • Nine exploration targets were identified, ready to be assessed and Fabio Vergara: [email protected] Chris Bonson: [email protected] potentially drilled by Excalibur

11 Howard Baker

Howard Baker, Maximising drilling to define the mineral MSc, Principal Consultant resource at the Nkout Iron Ore project (Mining Geology), has 15 years of broad geological experience in mineral resource estimation, mine geology and exploration planning. He worked as a senior mine geologist in the iron ore and mineral sands industries in Western Australia before joining SRK in 2007, where he has focused on resource block modelling of iron ore deposits in West Africa, Sweden and Finland. Howard’s SRK responsibilities include generating geological models using specialised mining software, producing resource estimates, auditing mining operations as part of Competent Person’s Reports and Stock Exchange Listings and technical due diligence reviews. Resource definition drilling at the Nkout Iron Ore project, Cameroon Howard Baker: [email protected] In September 2010, Afferro Mining mineralisation from 10 drillholes, Colin Rawbone Inc. commissioned SRK to conduct and the specific drill targeting of the maiden Mineral Resource the potential oxidised sequence Estimation (MRE) on their 100% overlying the BIF with 21 shallow, Colin Rawbone, owned greenfield Nkout Iron Ore vertical drillholes. The results of the MSc, Consultant project in Cameroon. The project is exploration drill program showed (Resource Geologist), being managed by an SRK Qualified that a high-grade iron concentrate has over six years’ Person for iron ore projects. could be generated from the primary field experience in BIF after 94 representative samples Through regional geophysical surveys, mineral exploration were selected by SRK for Davis Tube Afferro had identified a 20km strike in west and central analysis. They showed that Nkout had length magnetic anomaly within African gold and an oxidised cap with the potential to the Djoum exploration licence and iron ore deposits. generate early cash flow from high- had confirmed the existence of His professional career includes project grade direct shipping ore (DSO) and a an iron bearing sequence through evaluation and assessment, planning softer, friable BIF that could generate surface grab samples. SRK assisted and supervision of drilling activities, 3D a high-grade sinter fines product in the drillhole planning, assaying, geological interpretation and modelling, through a simple gravity circuit. The preliminary metallurgical testwork and resource estimation, and preparation maiden MRE covered the Nkout quality assurance and quality control of compliant NI 43-101 documents. He centre target, comprising 3.5km of protocols for the drilling program has managed the technical aspects of the 20km magnetic anomaly. projects from discovery to resource that enabled Afferro to estimate a development and bankable feasibility 1- billion tonne (Bt) maiden MRE in After the success of the maiden MRE, studies. Since joining SRK in early 2011 the Inferred Resource category from Afferro retained SRK to manage the Colin has focused on mineral resource 4,359m of drilled meters. Critical ongoing exploration drilling with a estimation, including 3D geological to their success was targeting the qualified SRK Exploration/Resource models and geostatistical analysis. primary banded iron formation (BIF) Geologist based on site throughout

Colin Rawbone: [email protected]

12 Deciphering structural controls in a greenstone belt in Ghana

In March 2010, Xtra-Gold Resources acquired drill core, SRK identified several Corp. commissioned SRK to conduct a northeast-trending shear zones that structural geology analysis of their Kibi bound auriferous stockworks in the diorite Project that aimed to provide insights intrusions. In addition to controlling the to the geological and structural controls development of stockwork veins in diorite, on the distribution of gold mineralisation these shear zones host auriferous fault-fill and guide further exploration. Xtra-Gold and extensional veins. Structural analysis also commissioned SRK to conduct of shear zone and vein elements indicated a structural interpretation of regional that these developed during protracted airborne geophysical data, with the aim SE over NW compression. Moreover, of developing a litho-tectonic framework identification of the auriferous shear zones for the region that could be used for allows Xtra-Gold to better focus regional defining conceptual structural targets. exploration drilling along this newly-defined prospective structural corridor. Xtra-Gold’s Kibi Project is located in the underexplored Kibi-Winneba Ivo Vos: [email protected] greenstone belt in Southeast Ghana. Although SRK has previously conducted numerous geological studies in other Ivo Vos belts in Ghana, little is known about the tectono-metallogenic evolution of this belt. SRK investigated Xtra-Gold’s Ivo Vos, PhD, drill core and exploration trenches to P Geo, is a Senior Resource definition drilling at the Nkout Iron Ore project, Cameroon unravel the geology and controls on Consultant in gold mineralisation and developed a Structural Geology the 2011 program. This allowed a structural framework that is the first of with SRK Toronto. dynamic approach to the drilling and its kind in this belt. He has over 8 years of experience in the allowed the MRE to proceed with the SRK was able to determine that gold regional and local geological modelling completed as mineralisation at the Kibi Project structural analysis new drillholes are logged and the drill occurred in quartz-albite-ankerite of mineral deposits and has successfully program adapted accordingly. Afferro stockwork veins within quartz diorite applied his knowledge to the discovery of could now maximise the drilling intrusions, and quartz-carbonate new gold deposits in East Africa. Ivo is an budget, getting absolute value from veins in narrow northeast-trending expert in deciphering structural controls every meter drilled and ensuring that graphitic shear zones that occur in on the distribution of mineralisation with international standards are followed. tightly folded metasedimentary rocks. experience in a variety of commodities, Gold mineralisation in the quartz After the maiden MRE and an including Gold, Ni-Cu-PGE and Uranium. diorite intrusions appears to be more additional 5,505m of drilling were His other specialties include deposit-scale widespread and forms the focus of Xtra- completed, Afferro announced an 3D modelling, structural and geological Gold’s ongoing exploration campaign. increase in the resource base to 1.4Bt interpretation of geophysical data, (multi- with 700 million tonnes now upgraded The recognition that gold mineralisation commodity) regional exploration targeting to the Indicated category and tonnage was primarily hosted in quartz diorite studies, and GIS integration of geological, to the DSO material increased. allowed Xtra-Gold to focus its exploration geophysical and lithogeochemical data. Exploration continues and future drilling, and better define the 3D geometry Ivo Vos: [email protected] resource updates are pending as over of these intrusions and the extent of 9km of the 20km defined magnetic auriferous zones within them. Following anomaly have now been tested. further structural analysis of subsequently Howard Baker: [email protected] Colin Rawbone: [email protected]

Nugget containing >30 oz gold discovered at Xtra-Gold’s Kibi Project in April 2011

13 Project diversity and foreign interest spur SRK India’s growth and success

SRK established its Kolkata, India, The first step to any geological study presence in 2006. Since then, the is geological mapping. Successful office has expanded in response to geological mapping includes geospatial client needs and an ever-growing client documentation, subsurface projection of base. SRK India provides a range of geological surface features, and accurate services from auditing and competent- identification of geological features and person reporting to exploration project rock types. SRK India has undertaken advisory, drill program design, and multiple mapping programs. Some sampling protocol implementation. of these have revealed unidentified mineralised bodies, including an iron While domestic Indian companies ore mine in India and a 1000-square are now investing in various mining kilometer coal project in Zambia. geographies across the globe, private investments within the Indian mining In 2010, SRK India consulted on an sector have also gradually increased. Indian gold project, which involved a These companies and investors look to data review and field visit, as well as SRK India to evaluate and audit early- resource potential assessments and to-advanced stage exploration projects, exploration planning. As a result of develop and manage exploration that work, the client further retained programs, and prepare independent SRK India for a scoping study, in which technical reports for potential funding. additional field and laboratory test work was recommended so the client could undertake a feasibility study.

Souvik Banerjee SRK India has also provided client training, developed field protocols based on international best practices, and Souvik Banerjee, a helped design exploration databases. For Geologist at SRK’s example, Aryan commissioned SRK India Kolkata office, to assist with its exploration program for has nine years their Narayanposhi iron ore project and of experience. Trimex for their Beach Sand project. In SRK structural and resource His skills include both cases, SRK India provided support geologists work closely with clients structural mapping to ensure the integrity and reliability to deliver resource estimates that and interpretation, of the exploration databases were incorporate sophisticated geological 3D modelling, achieved. Eventually, both companies and structural models. Since 2007, exploration planning and managing produced mineral resource reports SRK has assisted Rainy River greenfield to brownfield projects, following JORC code. Resources Ltd. to develop detailed sampling and assay quality control and resource evaluations for the Rainy mineral resource evaluation. Since joining Another project also highlights SRK River deposit based on evolving, SRK in 2008, Souvik has worked on base India’s growth and success since 2006. constrained structural models. The metal, gold, manganese, iron ore and coal When Coal India Limited launched its Rainy River deposit is a strongly projects in India, Indonesia and Southern IPO in 2010, the company appointed deformed, gold-rich volcanic massive and Western Africa. Souvik has been SRK India to benchmark its exploration sulfide-associated gold deposit involved with projects requiring early protocols and resource estimation located in northwestern Ontario, appraisal, reviews and audits, exploration practices according to international best Canada. The deposit consists of a development and independent technical practices. Coal India used this work to number of distinct resource zones, reporting following JORC and NI 43-101. report its resources and reserves, which the largest being the ODM17 zone. were compliant with the JORC code. Souvik Banerjee: [email protected] In 2008, SRK was commissioned to Souvik Banerjee: [email protected] undertake a revised resource estimate Shameek Chattopadhyay: for the Rainy River deposit. As an [email protected] integral component of this process, SRK geologists visited the project site and

14 Blair Hrabi

Integrating structural geology for Blair Hrabi, M.Sc., P.Geo., is a Senior improved resource modelling Consultant with SRK, based in the Toronto office. He is a Structural Geologist with 18 years’ experience with the exploration industry, government geological surveys and in academic settings mapping and modelling the lithology, structure and mineral deposits in deformed Archean and Proterozoic terranes. Blair applies his expertise to evaluating the structural controls on lode gold deposits, to 3D Inclined view to southwest computer modelling of gold, magmatic of LeapfrogTM model shows nickel and VMS deposits for resource detailed resource domains evaluation and drill targeting, and to in the ODM17 zone, Optical GIS-based structural interpretations TeleviewerTM derived foliation disks, foliation of aeromagnetic data for exploration trends (red) and high strain targeting. zone trends (yellow). Blair Hrabi: [email protected]

Shameek Chattopadhyay conducted a structural interpretation and oriented core programs into the Shameek based on unoriented drill core. Evidence geological interpretation. SRK and Chattopadhyay, a for a penetrative south-dipping foliation, Rainy River personnel confirmed the Senior Consultant accompanied by a strong southwest- strong southwest-plunging lineation and (Geology) based at plunging stretching lineation that delineated distinct domains, consisting SRK’s Kolkata office, overprinted the gold mineralisation, of slightly different foliation orientations has over 8 years were critical observations. Most styles within the ODM17 zone. High strain of experience. His of gold mineralisation in the ODM17 zones at the structural base of the broad background zone are clearly deformed by this strong ODM17 zone and bounding internal includes exploration ductile deformation, and both sericite zones of increased gold mineralisation management, alteration halos and gold mineralisation were traced through the deposit. analysing assay quality control data, envelopes plunge approximately parallel These observations were used as the 3D geological modelling and mineral to the stretching lineation. The initial geological rationale for constructing resource estimation. Since joining resource modelling incorporated these better constrained resource domains SRK in 2007, Shameek has worked on structural observations to define a (Figure 1). The practical implementation multiple resource estimation projects series of geodomains consistent with of detailed structural analysis resulted and technical due diligence studies the foliation and stretching lineation in a resource model with increased associated with Stock Exchange Listing. orientations. geological confidence that reduced His major commodity specific experience the level of risk associated with the covers base metals, gold, iron and In 2010, SRK was commissioned to resource estimate. manganese. undertake a further structural study. At this time, SRK was able to integrate Blair Hrabi: [email protected] Shameek Chattopadhyay: recently acquired Optical TeleviewerTM [email protected]

15 Effective geological training and data management

Bill Kellaway

Bill Kellaway is a Principal Exploration Geologist with SRK Exploration Services. He has 29 years’ experience in the oil, mining and educational sectors. Bill previously worked in exploration and mine production on a number of tin and gold deposits in South America and South Africa for Gold Fields Ltd before joining SRK Exploration in 2009. Since then, he has managed a number of successful exploration programs coupled with training in West and Southern Africa, Basic geological training of field geologists, Botswana Europe and North America. Bill Kellaway: In recent years SRK Exploration SRK ES has developed structured [email protected] Services noticed that the fast pace of geological tuition programs revolving modern exploration often occurs at the around a Training Checklist designed expense of quality data management to assess current competency and James Gilbertson and geological training. identify training needs. These programs are run as informal workshops for The current demand for experienced individuals or groups and ideally form ames Gilbertson geologists shows little sign of abating J part of annual assessments of an has over 12 years and the need for training has never individual’s continuing professional of experience in been greater. University curricula are development. A Training Manual mineral exploration stretched and training in the field is accompanies the workshops, outlining and resource often left to industry, where in-house standardised procedures for all aspects modelling, training programs are now a thing of of exploration activities ensuring including 7 years the past. industry best practices. as a consultant At SRK ES, we recognise that many of with SRK. James Recent training programs were run our clients rely heavily on under-trained has performed many geological and on three levels: basic geological staff, supplemented only periodically exploration program audits, due diligence techniques, design and implementation by expatriate technical managers, and reviews, and competent person reports. of standard protocols, and exploration training now forms an intrinsic part He now specialises in exploration management and logistical support. in many of our commissions. While program design and implementation, This approach is most effective when geological training is most apt for new technical reviews and data management pitched at the right level, where there and young recruits, SRK ES recognises as a Principal Exploration Geologist with is continual feedback and a proper the need for continual training at every SRK Exploration Services. mechanism for ongoing assistance and level to ensure competency in all support. James Gilbertson: aspects of project work. [email protected] In many current exploration projects,

16 Exploring for specialty metals in Greenland

In 2010, Ram Resources Ltd. Working alongside SRK ES, SRK commissioned SRK Exploration Services Consulting (UK) will soon start work to assist with the review and acquisition on the first Inferred Resource for the of the Motzfeldt tantalum-niobium project. Further drilling is planned for (Ta-Nb) project in South Greenland. 2012 to expand this resource and to SRK ES undertook an in-depth further investigate the new regional assessment and due diligence on the exploration targets identified in 2011. data available for this project, which was thought to be one of the world’s largest Ram Resources is a small company occurrences of Ta-Nb hosted in altered with limited in-house geological syenites. Motzfeldt forms part of the expertise. By working with SRK ES, Gardar Alkaline Province, located in a they have benefitted from the remote and mountainous sub-Arctic area services of an experienced and multi- with access possible only by helicopter. disciplinary team that has enhanced their understanding of this unique but In 2010, SRK ES mobilised an Arctic- challenging geological region. experienced team to carry out a drilling, trenching and sampling program that Jon Russill: [email protected] highlighted the limited nature of earlier exploration, as well as considerably expanding known mineralisation, and Jon Russill identifying significant rare earth element (REE) mineralisation that had previously Basic geological training of field geologists, Botswana been overlooked. Further exploration Jon Russill has 11 programs were completed in 2011, along years’ experience in with intensive, helicopter-based, regional mineral exploration SRK ES has identified another area that and geophysics would benefit from training: effective geological and geophysical exploration. 2 and is a Senior data management and interpretation. The The area was covered by a new 568km licence that was applied for following Exploration Geologist adage “data rich, but information poor”’ is with SRK Exploration particularly true for early stage exploration review of historical data. This project guided the identification of four new Services Ltd. He projects where true geological complexity specialises in the is yet to be understood. areas of Ta-Nb-REE mineralisation in a range of geological settings. design, management and technical To address this need, SRK ES has review of exploration programs and developed specific capabilities for client In cooperation with a range of has worked on a variety of commodities data storage, management, interpretation laboratories, SRK ES also designed around the world. Recently, Greenland and visualisation, along with assistance in specific sampling, assaying and quality has been a major area of focus, selecting and developing tailored in-house control procedures to best assess what especially in generating targets for rare programs for effective data utilisation. are very complex elements and matrix earth mineralisation. Jon has also been styles, in a most time-effective manner. extensively involved with exploration for As exploration projects are fast-tracked gold in West Africa, and he is actively towards resource projects, exploration building the exploration geophysics teams with robust systems and protocols capabilities of SRK ES. in place, and effective tools to deal with their data, are best positioned to benefit Jon Russill: [email protected] from any corresponding addition in value.

James Gilbertson: [email protected]

Bill Kellaway: [email protected]

Reconnaissance exploration in remote areas of the Igaliko Alkaline Complex, Greenland

17 Advanced exploration targeting: SRK’s approach

SRK has a great deal of experience concept of geological processes, in in assisting companies to implement which mineralisation, moving from a minerals exploration programs from source along a pathway, is focused greenfields to advanced projects. The and becomes localised in a trap. Each initial stage of any exploration program element is ranked, based on the is targeting. At this stage, exploration geologist’s judgment, and the features are activities are focused onto specific combined in a 2D or 3D GIS package. The areas with the highest potential for cumulative effect of intersecting features discovery, and on developing strategies of interest highlights target areas. to systematically explore them. Data-driven targeting methods provide Unfortunately, dedicated exploration a robust and repeatable technique for targeting is often overlooked. investigating regions with large amounts Ideally, targeting shouldn’t create too of data, particularly in brownfield many false leads, but equally shouldn’t exploration. The data-driven approaches be so simplistic that it misses the next require little understanding of the big one. When assessing the exploration actual mechanism of mineralisation, potential of large areas, decisions should but use empirical evidence to rank each be based on a combination of available element. The most common approach data and expert knowledge. Predictive is the Weights of Evidence technique, tools use the characteristics of known where a spatial feature (e.g. fault, mineral deposits to identify similar geochemical anomaly, specific rock Intelligent 3D drill planning based on a combination features in exploration datasets such as type) is assigned a statistical weighting of structural mapping and magnetic inversion results geochemistry, geology, structure and based on its statistical relationship (iron ore project in Guinea, West Africa) geophysics. Expert-driven and data- with identified mineralisation. This driven are the two different approaches approach allows even very large and Having worked for SRK on a wide used in predictive targeting. complex datasets to be integrated in variety of exploration projects, I’m an unbiased manner. In many cases, The expert-driven approach to exploration sad to report that geological and features related to mineralisation can be targeting relies on understanding the structural mapping continues to be a identified, allowing exploration to focus mineralising system or potential for a largely undervalued exploration tool on prospective regions, independent of minerals system to occur. It is useful in the industry. Finding a geological past interpretations. in greenfield areas where information map in the display booths at explorer’s regarding mineralisation is limited. The targeting processes SRK has conferences is a bit like the industry The areas can be compared with developed provide a robust geological itself: high risk – low gain! similar geological settings with known framework and mineralisation models This lack of interest in mapping in mineralisation, where an exploration on which companies can base part reflects the fact that market model or rationale for future exploration exploration programs. appetite is focused on vague can be developed on sound geological Matt Greentree: [email protected] declarations of “mineralised corridors” reasoning. This approach uses the and “prospective structures”. And the fast pace at which exploration projects operate allows little time for mapping, which is perceived to be slow work. As a consequence, mapping skills are dying out, and many younger geologists lack the mapping skills needed to make sensible interpretations.

SRK believes that geological and structural mapping should be conducted early in any project, to form a solid basis for a cost-effective Weights of Evidence prospectivity map for greenstone hosted orogenic gold targets in the Yilgarn Craton, Western exploration campaign. The cost of Australia

18 Cheap and dirty, but essential: geological/structural mapping

Bert De Waele

Bert has over 20 years of structural mapping experience, mostly in African Precambrian terranes. He has consulted on base metal and gold prospects, setting up and running exploration programs or interpreting regional geochemical data. Bert has conducted Independent Technical Assessments on various mineral assets including gold, porphyry copper, iron ore, manganese, diamond, mineral sands, phosphate, evaporite and uranium. He has developed both expert and data-driven exploration targeting systems for gold exploration projects. initial geological mapping fades into for petrographic, chemical and even insignificance when compared with geochronological analyses, which may Bert De Waele: [email protected] drilling or regional geochemical or assist in geological interpretations. geophysical surveys. What’s more, the understanding gained by geological Recent mapping work conducted by Matt Greentree mapping allows a better definition SRK Perth include iron, base metal and of meaningful and cost-effective drill gold projects in Australia, West Africa, atthew has hole planning, defining target areas Southeast Asia and North America. M some 15 years for geochemical or geophysical work The mapping has ranged from regional of experience in and establishing a testable geological/ (1:50,000) to prospect scale (1:5,000) mineral exploration structural model. projects, sometimes incorporating 3D drilling data to aid interpretations. geology, and In recent years, the SRK Geology Team has international has developed advanced mapping SRK mapping has assisted clients to experience working capabilities using GPS-enabled tablet identify target areas, by recognising on numerous deposit PC’s and mapping protocols that allow outcropping mineralisation, or styles, including lode the digital capture of mapping data in structural interpretations, and where gold, IOCG, sediment-hosted Cu–Co and the field, producing maps more quickly data are sufficient, has provided a base metal deposits, magmatic nickel, than ever before. A geological map in testable geological model, in some and BIF-hosted iron ores. He has worked digital form and all attached databases cases, with exploration target sizes. on various grassroots and advanced are usually finalised within a week of Often, SRK is able to incorporate nickel exploration projects in China and finishing field work. The mapping data the surface mapping data into 3D Central Australia and regularly consults is integrated into a 3D environment geological models once drill data in the management and interpretation of (LeapFrogTM) to assist in cross-section become available. This in turn leads to geological and exploration data within generation and drill planning, and is better constrained geological domains, geological and GIS computer packages. presented to the client in GIS and and a more reliable resource estimate Matt Greentree: [email protected] LeapFrog format. SRK also works further down the line. with a set of reputable laboratories Bert De Waele: [email protected] to allow for quick sample returns

19 Overview of uranium exploration and the nuclear industry in Argentina Pablo Navarra

Pablo Navarra, Principal Geologist in SRK’s office in Mendoza, Argentina, has had a long career with the National Atomic Energy Commission of Argentina, specialising in the fields of uranium mining feasibility and operations, related environmental studies and exploration. Milestones included the Cerro Solo prefeasibility project, and the re-engineering of the Sa. Pintada Mine. He completed and published studies about gamma logging for uranium deposits evaluation, and took part in International Atomic Energy General view of the uranium mine-mill located in the Sa. Pintada Range, Mendoza Province, Argentina Agency activities related to world uranium resources. He was designated rgentina’s long experience in the 20 years, until 1997, when the Sierra Mining Director of the Province of A nuclear industry is evident not only Pintada Mine-Mill Complex, Mendoza Mendoza (October 2008 - May 2010). in continuously generating electricity, Province, was put on stand-by for Pablo Navarra: [email protected] 10% on average of Argentina’s national economic reasons. Then, five years ago, consumption since 1974, but also for the government launched a reactivation the companies associated with the program, by completing the construction Ernesto Jaramillo government-owned National Atomic of a third nuclear power plant and, Energy Commission (CNEA) that effectively reinitiating development of a Ernesto is a supply nuclear reactors for research national, low-power technology reactor. Principal Geologist and radioisotope manufacture for the These measures conform with proposals in the Santiago international market. CNEA’s technical of energy experts directed at increasing office with more teams began exploring and mining- nuclear participation in the energy than 20 years milling uranium in the 1950’s, but only a sector, reducing dependency on oil and of professional few geologically appropriate areas have gas imports. At the same time, CNEA’s experience. He been explored since then. teams, along with junior and senior has spent 14 years Now, based on results from exploring private companies, are taking new in lithological, sedimentary basins and granitic initiatives in uranium exploration, spurred alteration, mineral zone and and volcanic related areas, further on by rising international uranium metallurgical modeling, specifically in developing uranium resources beyond prices. Reactivating uranium production resource modeling and estimation. He national requirements seems feasible. and increasing resource exploration also has a background in underground Meanwhile, investigating areas are relevant activities for minimising and open pit production geology. As that could be mined using in-situ dependence on foreign uranium supply head of the resources/reserves group leaching, are just beginning, and some for fuel in the long term. in Santiago, Ernesto’s projects have interesting surficial deposits were taken him to locations throughout the At present, CNEA has plans for re- discovered in recent years. Americas as well as to Turkey. starting production in Sierra Pintada, Indigenous uranium production fueled and reaching the production stage in the Ernesto Jaramillo: [email protected] the operating nuclear power plants for Cerro Solo Project in Patagonia, although

20 New life for an old mine – Carmen, Chile

The Carmen iron mine is located in the workings. The workings consist of three northern Chilean Province of Chañaral levels that are located behind the south and lies approximately 50km east wall of the open pit. The levels extend of the coastal port city of Chañaral. for about 50m vertically and the lowest Since May, 2010, Minera Santa Fe has level, number 3, is about 10m below been producing a dry magnetite iron the lowest point of the pit bottom at concentrate from old stockpiles originally 800masl. A I-Site scanner survey was derived from the open pit, idle for 40 conducted in the open pit and all the years. SRK recognised the possibility of underground workings. adding resources at the Carmen project SRK’s Santiago geologists are able to by exploring the iron potential of the design and run exploration programs, alluvial gravels east of the old pit, as construct geologic models and perform well as the potential of the mineralised resource-reserve estimations, as well as material in the pit, either by extending the integrate their services with the mining depth of the high grade zone in the old department. This has allowed SRK to underground workings or by expanding continue working on this project through the pit itself. Drilling has been conducted the early engineering phases. on these targets and considerable new resources have been added to the project. George Even: [email protected] Ernesto Jaramillo: [email protected] Minera Santa Fe (MSF) has used SRK in Santiago as a consultant to do the geological exploration on most of their projects and they contacted SRK to George Even work at Carmen on this brownfield exploration program. SRK is constructing a new geological model based on George Even is a both projects face difficulties related to additional infill drilling and will produce Principal Geologist obtaining permits. Waste remediation a new resource estimate. Once this is and Partner in is being carried out or is under study completed, a mining scoping study will SRK’s Chile office. at former mining-milling sites. The be performed. SRK has already done His 39 years of efficient completion of remediation will a preliminary economic study of the experience range be very important for obtaining social project for MSF. The results are very from grassroots licenses for new production, as the positive and MSF plans to move the exploration programs social perspective on nuclear and mining project ahead as quickly as possible. to open pit stability activities is as controversial here as in design. After spending 10 years in MSF is currently producing from a new other countries. exploration and mining in North America, plant, which will treat all the ore types at he has based his operations over the Carmen. The plant will process 500,000 SRK may play a role in future nuclear last 29 years in Santiago. His project tonnes of material per month. activities in Argentina by supporting experience includes designing and uranium exploration and production, Carmen is one of the few iron mines in implementing exploration programs and both private and government-run. Chile where a massive magnetite ore developing structural and geotechnical SRK’s experts have experience in zone is well exposed in the underground models. He has conducted numerous all stages of uranium production, technical and due diligence reviews in environmental studies, and mine throughout South and Central America. closure and remediation. SRK is currently involved in selecting consulting George Even: [email protected] companies for remediation of a closed uranium production center. In furthering exploration activities performed by private companies, SRK’s Santiago, Chile office carried out some advisory studies, and maintains contacts for continuing services involving the Mendoza Office.

Pablo Navarra: [email protected] Carmen Pit looking north

21 Applying the box plot method The future of 3D modelling in consulting Since footwall alteration zones are the deformation and metamorphism, related to volcanic-hosted massive may be recognised in exploration by sulfide (VMS) deposits, their unique studying the geological and chemical features provide likely targets for composition of their rock formations. exploration. Of these, the chloritic The massive sulfide deposit in the footwall alteration pipe is the most eastern part of South Africa’s Namaqua characteristic of VMS deposits. This Province, at Areachap, Kantienpan and feature is identified geochemically the defunct Prieska Cu-Zn Mine are by a strong relative enrichment in hosted in the Areachap Group, formed aluminium and magnesium, coupled by volcano sedimentary layers of the with depletion in calcium and sodium, mid-Proterozoic era. These deposits giving rise to chloritic rocks. During were affected by a complex deformation metamorphism such rocktypes and metamorphic history. are replaced by rocks containing magnesium-rich cordierite, phlogopite, Applying known lithogeochemical orthoamphiboles or orthopyroxenes methods is especially complicated and aluminium-rich minerals, such as where the geology is not well sillimanite and corundum. As such, understood, due to the poor rock the unusual geochemical features of exposure, as in the eastern part of the the alteration zone, retained during Namaqua Province.

The box plot presents a method that can readily be used to identify the Hennie Theart alteration process, but it was designed for relatively un-metamorphosed Hennie Theart, a environments. This study demonstrates Principal Geologist that the box plot may also be applied with SRK Consulting to high-grade metamorphic terrains, Historically, SRK has been at the (SA), has over 30 replacing the low-grade metamorphic forefront of developing advanced years experience mineral assemblage with its high- geological and mine modelling methods in exploration grade equivalent. The trends in mineral from the early Gemcom days until the geology, economic composition themselves may be used in development of Leapfrog Mining with geology, mineral defining the box plot. These include, for ARANZ. SRK consultants saw the need valuation, exploration example, the transition from annite to for a rapid grade modelling tool to replace methodology and mining geology. phlogopite and hornblende to gedrite or CAD early, and our strong relationship cummingtonite. with software developers continues. His expertise includes the genesis of volcanic base metal sulfide deposits, Conclusions based on using the graphic The ability to generate logic-based exploring for, and the mining of various solution known as the isocon method geological 3D models for exploration with base, rare, and precious metals, demonstrated that primary footwall speed and accuracy, seems not that far industrial minerals and gemstones. alteration zones in the Areachap Group’s away. There is healthy competition from Hennie specialised in geochemistry VMS deposits are characterised by the GoCad, Leapfrog and Geomodeller for including both soil and lithogeochemical predicted depletion and enrichment of this type of solution. exploration. As a Professor he taught elements, as expected. The whole rock SRK’s business unit in Perth – our Economic Geology and Mineral compositions that were independently Advanced Modelling Laboratory – uses Evaluation for eight years at under-, and identified as the equivalents of altered the latest rapid modelling techniques to post-graduate levels and supervised rocks plot in the correct place in the solve geological, hydrogeological and various post-graduate studies on base box plot for high-grade regionally geotechnical problems from early stage metals, nickel sulphides, gold, diamonds, metamorphosed terrains, establishing exploration to resource estimation and coal, and platinum group elements. the box plot as an effective and practical exploration tool for VMS deposits. advanced mine design. Hennie Theart: [email protected] Dr Hennie Theart: [email protected] Quo Vadis? Leapfrog recently developed general geological modelling that responds

22 The future of 3D modelling in consulting

Peter Gleeson

Peter has over 29 years of experience in both consulting and production roles. He has worked on resource estimation projects, project evaluations and 3D modelling studies for a variety of different geological environments and commodities, ranging from precious, base metals, and uranium through to iron ore. Peter has implemented several innovative geological modelling technologies which have helped to improve their Three dimensional geological model of the subsurface with surficial (2D) mapping overlaid effectiveness and the way in which companies produce 3D geological models and interpretations to facilitate to industry needs and can produce SRK Advanced Modelling Laboratory the exploration and evaluation of effective solid and surface models mineral deposits. He is an expert of faults, intrusions and geological The SRK Advanced Modelling Laboratory focuses on providing solutions that move user of several mining and geological formations, using the same intuitive modelling software packages such as interface and work flows that made away from 2D to 3D geological models to explore at ever-increasing depth. Vulcan, GOCAD, Geomodeller, FracSIS, previous Leapfrog capabilities Leapfrog and Datamine. so powerful. Where Leapfrog’s Currently, 3D GIS2 is in its infancy; 3D model was difficult to validate, new map products that drive research and data Peter Gleeson: [email protected] software tackles this problem with collection are costly and lack specialised relatively simple geological models expertise. And scale depends on explicit quite successfully. However, these modelling techniques, complicated by the packages are either expensive or still in inability to validate models in 3D against development and have not gained wide multiple datasets. • Provide workflows for domain definition acceptance. Applying more general geological from regional to resource scale and modelling has a low cost-to-benefit ratio, geological control for resource domains ARANZ has developed geological and regional/tenement maps modelling for less complex with potential to generate rapid 3D maps, requirements (Leapfrog Hydro and ease of validation against 3D data, and • Incorporate 3D GIS to search for buried Leapfrog Geothermal). These more scale independence of the modelling deposits simplistic, stratigraphically-controlled process. The ability to model numerous • Build complex geological models for geological models do not compare geological domains rapidly and effectively clients quickly at significantly lower cost with sophisticated models for multiple- will allow clients to generate regional- and tenement-scale exploration models, deformed gold deposits. They work, • Use model simulation to reduce risks, reducing risks inherent in resource however, for many minerals modelling providing many scenarios instead of a estimation on poorly domained deposits. problems, such as iron ore, bauxite, and single model coal. The Quo Vadis question, then, is The SRK Advanced Modelling Peter Gleeson: [email protected] how to build on this capacity to solve Laboratory intends to use new software Peter Williams: [email protected] more generalised modelling problems. technologies to:

23 Specialist advice for mining projects in all global environments.

To learn more about SRK and how we can help you with your next challenge, visit our website: srk .com