Lake Superior-Type Iron Formations in the Labrador Trough An Overview

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1 Lake Superior-Type Iron Formations in the Labrador Trough An Overview James Conliffe Mineral Deposits Division Geological Survey of Newfoundland and Labrador Mineral Resources Review 2012 CIM-PEGNL Short Course

2 Iron Ore in the Labrador Trough World class iron ore district, having produced in excess of 2 billion tonnes of iron ore since 1954 Six active mines in the Labrador Trough (four located in Labrador)

3,500,000 3,000,000 2,500,000 2,000,000 1,500,000 1,000,000 Iron Ore Copper Nickel Other-Metals Non-Metals 500,000 0 2012f 2011e

3 Iron Ore in the Labrador Trough Gross value of iron ore shipments in 2012 forecast to be >$3.8 billion, second only to oil industry in economic importance to Newfoundland and Labrador Gross value ($000 CAD) 4,000,000 3,500,000 3,000,000 2,500,000 2,000,000 1,500,000 1,000,000 Iron Ore Copper Nickel Other-Metals Non-Metals 500, f 2011e 2010p data from Newfoundland and Labrador Department of Natural Resources Numerous advanced exploration projects with potential to greatly increase this contribution

4 The first reference to iron was made by a Jesuit priest, Fr. Babel, who travelled in the region from 1866 to 1870, but the first descriptions of iron ore and its potential importance come from the pioneering geologist Arthur P. Low in the early 1890s A. P. Low V. Eaton

5 before leaving this part of the river, attention must be drawn to the immense amount of rich iron ore seen about the shores of the lakes, which can only be estimated by millions of tons

High-grade hematite ores discovered in the Knob Lake area in 1929 just before the depression.

Iron Ore Company of Canada (IOC) formed in 1949.

6 High-grade hematite ores discovered in the Knob Lake area in 1929 just before the depression. Prospecting for base-metals and iron from 1933 to 1945 an effort led largely by Joseph Retty. Iron Ore Company of Canada (IOC) formed in Production of iron ore from the Schefferville area began in 1954, following construction of the QNSL from Neal, 2000 railroad. Lab City/Wabush area deposits explored, and enter production in 1962 (IOC) to 1965 (Wabush Mines) Schefferville deposits ceased production in 1982, but not exhausted - production resumed in 2011.

7 Precambrian Iron Formations from Bekker et al. (2010) Stratigraphic units of bedded or laminated sedimentary rocks or layered metasedimentary rocks with > 15% Fe Subdivided into two main types Algoma-type iron formations are associated with submarine-emplaced volcanic rocks, especially in greenstone belts Lake Superior-type iron formations formed on continental-margins, without direct relationships with volcanic rocks

8 Lake Superior-type Iron Formations Peaks in iron sedimentation between ~2.65 and 2.32 Ga and again from ~1.90 to 1.85 Ga Deposition linked to geochemical and environmental evolution of Earth Great Oxidation Event (GOE) at ca. 2.4 Ga Growth of continents Mantle plume activity and rapid crustal growth from Bekker et al. (2010)

iron in deep anoxic ocean basins (possibly linked to VMS deposits, Bekker et al.

9 adapted from Clark and Wares (2004) Iron ore deposits in the Labrador Trough classified as Lake Superior-type granular iron formation (GIF) Hydrothermally derived iron in deep anoxic ocean basins (possibly linked to VMS deposits, Bekker et al. 2010) Deposition on near-shore continental shelves close to or above storm and fair-weather wave base

Ranges of the USA Forms the western part of a larger orogenic belt called the New

10 Labrador Trough Part of a vast Paleoproterozoic sedimentary basin developed around the Superior Craton Correlative rocks occur in the Mesabi and Marquette Ranges of the USA Forms the western part of a larger orogenic belt called the New Quebec Orogen Iron formation hosted in the Knob Lake Group of the Kaniapiskau Supergroup

11 Labrador Trough Knob Lake Group Two cycles of Paleoproterozoic (2.17 to 1.87 Ga) sedimentary and volcanic rocks Iron ore deposits hosted in the Sokoman Formation, towards the top of the second cycle m thick sequence of cherty iron rich sediments

important economically Iron-rich layers and lenses commonly containing more than 50 percent

12 Labrador Trough - Sokoman Formation Lower Iron Formation Member Silicate carbonate iron formation (minnesotite and siderite) with some magnetite Middle Iron Formation Member Most important economically Iron-rich layers and lenses commonly containing more than 50 percent hematite and magnetite Upper Iron Formation Member Green to grey or black magnetite-chert Generally iron-poor

14 Iron Ore Deposits in the Labrador Trough All iron ore deposits in the Labrador Trough formed as chemical sediments which were lithified and variably affected by alteration and metamorphism important effects upon grade, mineralogy and grain size Faulting and folding led to repetition of sequences in many areas, increases the surface extent and mineable thicknesses of the iron ore deposits 3 main types of iron ore deposits recognized in the Labrador Trough

in Upper iron Formation None presently mined in Labrador Trough important sources for iron ore

15 Taconite Deposits Fine grained, unmetamorphosed or weakly metamorphosed sedimentary iron formations (15 to 30% Fe) bands of iron oxides (magnetite and hematite) in quartz (chert)-rich rock Stromatilites in Upper iron Formation None presently mined in Labrador Trough important sources for iron ore elsewhere (e.g. Minnesota) potential for large scale mining operations in the future Jasper Upper Iron Formation

0 Ga) Recrystallization to coarser-grained Coarse grained metataconite (IOC Carol Lake) magnetite and

16 Metataconite Deposits Present in the southern part of the Labrador Trough Moderately to strongly metamorphosed during Grenville orogeny (ca. 1.0 Ga) Recrystallization to coarser-grained Coarse grained metataconite (IOC Carol Lake) magnetite and specular hematite Paleoproterozoic recumbent isoclinal folds are refolded to greatly increase the thickness of iron ore deposits Quartz-specularite schist (Julienne Lake)

Despite the close proximity of these deposits there are significant variations in terms of mineralogy, alteration and stratigraphy Magnetite/Hematite ratio Mn-rich horizons Deep weathering and

17 Despite the close proximity of these deposits there are significant variations in terms of mineralogy, alteration and stratigraphy Magnetite/Hematite ratio Mn-rich horizons Deep weathering and leaching Shared characteristics between some deposits implies regional correlations possible e.g. Julienne Lake, Scully Mine, North Rose and Wabush Mountain in Wabush Basin Implications for development of individual deposits Metataconite Deposits

and process as they require less beneficiation Historically mined

18 Direct Shipping Ore (DSO) Deposits High grade (<50% Fe) ores Formed from the enrichment of primary taconites Cheaper to mine and process as they require less beneficiation Historically mined in the Schefferville area from 1954 to 1982 Two broad classes of DSO deposits

Direct Shipping Ore (DSO) Deposits Soft, friable, fine-grained secondary

limonite) Leaching of silica and carbonate and associated iron enrichment

groundwater circulation and supergene enrichment associated with deep

19 Direct Shipping Ore (DSO) Deposits Soft, friable, fine-grained secondary iron ores Composed mainly of secondary iron oxides (hematite, goethite, limonite) Leaching of silica and carbonate and associated iron enrichment photo from New Millennium Iron Corporation Traditionally related to groundwater circulation and supergene enrichment associated with deep tropical weathering preferentially in synclinal depressions and/or down-faulted blocks

20 Direct Shipping Ore (DSO) Deposits from Gross (2009) Some deposits overlain by rubble ore with preserved Cretaceous wood and fossils

been described from a number of locations,

Schefferville No evidence of leaching or

21 Direct Shipping Ore (DSO) Deposits Hard high-grade (<60% Fe) hematite ores have been described from a number of locations, including Sawyer Lake, southeast of Schefferville No evidence of leaching or supergene processes May be related to early hydrothermal processes and structural controlled fluid flow (similar to deposits in Australia and Brazil)

Houston deposit Dual hypogene-supergene model?

22 Direct Shipping Ore (DSO) Deposits A number of deposits share characteristics of both soft and hard DSO ore types e.g. Houston deposit Dual hypogene-supergene model? Implications for future exploration for high grade DSO deposits high-grade zones beneath unaltered low-grade primary iron formations

23 Current production and exploration Current production concentrated in traditional mining camps Labrador City/Wabush Schefferville/Menihek North Advanced exploration programs with resource estimates are also proceeding at several other deposits in the region

24 Labrador City/Wabush

Labrador City/Wabush Producers Carol Lake (IOC - Rio

operations began in 1962 Reserves of crude ore - 1374 Mt

25 Labrador City/Wabush Producers Carol Lake (IOC - Rio Tinto) 13 separate ore bodies, with two active open pits (Humphrey Main and Luce) More than 1.3 billion tones of iron ore has been produced since operations began in 1962 Reserves of crude ore Mt at 38% Fe Complex parallel folds, which has increased the thickness of deposits to approx 400m

26 Labrador City/Wabush Producers Scully Mine (Cliffs Natural Resources Inc.) Operating since 1965 Produced ~3.2 million tonnes of iron concentrates in 2011 Reserves are 214 million long tons at 35% Fe Broad syncline modified by multiple folding events Substantial ore resources contain significant manganese (1 to 2.5%)

Labrador City/Wabush Advanced or Developing Projects Kami project (Alderon Iron Ore

slightly overturned anticlines and synclines Mills Lake Deposit consists of a gently

starting in 2015 NI 43-101 mineral resource estimate Measured and indicated resource

27 Labrador City/Wabush Advanced or Developing Projects Kami project (Alderon Iron Ore Corporation) Rose Central and North Rose deposits consist of a series of upright to slightly overturned anticlines and synclines Mills Lake Deposit consists of a gently east dipping tabular body Preliminary Economic Assessment (PEA) Commercial production starting in 2015 NI mineral resource estimate Measured and indicated resource of 1100 million tonnes at 29.% Fe inferred resource of million tonnes at 29.5% Fe

28 Labrador City/Wabush Advanced or Developing Projects Julienne Lake (Exempt Mineral Land) Evaluation in 2010 by Government of Newfoundland and Labrador commissioned to establish an NI compliant resource estimate Measured and Indicated: 867 million tonnes at 33.7% iron Inferred : 299 million tonnes at 34.1% iron

Interest deadline 14 th November 2012 the Julienne Lake iron deposit represents a very rare and unusual

29 Labrador City/Wabush Advanced or Developing Projects Julienne Lake (Exempt Mineral Land) Dominantly or quartz-specularite schists with approximately 50% quartz and 50% iron-bearing minerals Call for Expressions of Interest deadline 14 th November 2012 the Julienne Lake iron deposit represents a very rare and unusual opportunity to develop a major new mining project in the heart of an established mining camp in a politically stable country (MPH Consulting)

30 Schefferville Area/ Menihek North 10 km from McVeigh (1980)

Schefferville Area Producers James Mine (Labrador

deposit Full scale mining commenced in June 2011,

2 million tonnes of iron ore mined in 2011 Plans

deposits NI 43-101 compliant indicated resources

31 Schefferville Area Producers James Mine (Labrador Iron Mines (LIM)) Direct Shipping Ore (DSO) deposit Full scale mining commenced in June 2011, with 1.2 million tonnes of iron ore mined in 2011 Plans for expansion and development of numerous other deposits NI compliant indicated resources of 45 million tonnes at a grade 56.5% Fe on the James, Redmond, Denault, Knob Lake and Houston deposits

Schefferville Area Producers Tata Steel Minerals

DSO project 25 hematite deposits with Proven and

32 Schefferville Area Producers Tata Steel Minerals Canada Limited/New Millennium Iron Corp. DSO project 25 hematite deposits with Proven and Probable Mineral Reserves of 64.1 million tonnes at 58.8% Fe Initial mining and stockpiling of ore began in September 2012 Estimated to produce 2.0 million tonnes of sinter and super fines in 2013 Construction of steel supported fabric structure to facilitate year round production

33 Schefferville Area Advanced or Developing Projects New Millennium Iron Corp. Taconite Project Near-surface taconite deposits Flat-lying, unmetamorphosed and outcrop over a total strike length of some 30 km LabMag Project: Proven and probable reserve of 3.5 billion tonnes at 29.6% Fe photo from New Millennium website KéMag Project: Proven and probable reserve of 2.1 billion tonnes at 31.2% Fe Other exploration projects in Millennium Iron Range Feasibility report scheduled for completion by end 2012

Future Potential Numerous other iron occurrences documented across large areas of western Labrador and now focus of exploration Joyce Lake (Century Iron Mines Corp.

34 Future Potential Numerous other iron occurrences documented across large areas of western Labrador and now focus of exploration Joyce Lake (Century Iron Mines Corp./Champion Minerals) Snelgrove Lake (CIP Magnetite Ltd./Altius Minerals Corp.) Lac Virot (Ridgemont Iron Ore Corp.) Iron Horse Project/Gabbro Lake (Golden Dory Resources) Block 103 (Cap-Ex Ventures Ltd.) Sawyer Lake and Astray Lake (LIM) Labrador Trough Iron Ore Project (Century Iron Mines Corp./Altius Minerals) Labrador Iron Ore Project (Rio Tinto/Altius Minerals)

35 Closing Summary Future Resources The Labrador Trough is and will remain the major source for Canadian iron ore production Significant resources remain with potential for future production from new taconite, metataconite and DSO deposits Prospective rocks of the Sokoman Formation are present over wide areas in the hinterland, where there has been little historic exploration Scientific information mostly based on initial exploration in the 1950s and 1960s Future research into the nature and genesis of deposits necessary collaboration between industry, academia and government

Tata Steel Minerals Canada Alderon Iron Ore Corp.

37 Acknowledgements Department of Natural Resources Andy Kerr Wayne Tuttle John Clarke Garrett Martin Labrador Iron Mines New Millennium Iron Corp. Tata Steel Minerals Canada Alderon Iron Ore Corp. Century Iron Mines Corporation Iron Ore Company of Canada Cliffs Natural Resources Altius Minerals Corporation Golden Dory Resources Corporation MPH Consulting

Julienne Lake Iron Deposit. History, Evaluation and Path Forward

Julienne Lake Iron Deposit. History, Evaluation and Path Forward Julienne Lake Iron Deposit History, Evaluation and Path Forward What is Julienne Lake? The Julienne Lake deposit represents a large, undeveloped deposit of iron ore located in Labrador West. It is situated