Mineral Deposit Report Page 1 OF Geological Survey of Finland

Transcription

1 Mineral Deposit Report Page 1 OF Kotalahti Alternative Names: Oravikoski Occurence type: deposit Commodity Rank Total Total production Total resource Importance measure nickel ,62 t 82079,62 t NA Medium sized deposit copper t t NA Small deposit cobalt 2 NA NA NA NA platinum 5 NA NA NA NA sulphur 5 NA NA NA NA Easting EUREF: ,263 Easting YKJ: Northing EUREF: ,437 Northing YKJ: Discovery year: 1954 Province: Kotalahti (Ni, Co) District: Kotala (Ni, Co, Cu) References: 1, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 16 Mineral deposit type Group: Metallogenic deposit Main type: Magmatic References: 8, 12, 14 Dimension Expression: exposed Area (ha): NA Form: discordant Dip azim: 67 Shape: NA Dip: 85 Length (m): 1300 Plunge azim: NA Width (m): NA Plunge dip: NA Thickness (m): NA Orientation method: NA Depth (m): 1000 Holder history Current holder: Boliden AB Years: 2015 Holding type: Exploration permit Previous holders: Company Years Holding type Comments Vulcan Resources Ltd Claim (old law) NA Outokumpu Oy NA Years uncertain. 1

2 Mineral Deposit Report Page 2 OF Figures Airphoto: 2

3 Mineral Deposit Report Page 3 OF EXPLORATION ACTIVITY Outokumpu Oy Years Activity type Geologist Exploration result Ref regional geophysics J.Koskinen, M.Järvinen,T.Karppanen, H.Saarnio, G.Gaál, L.Grundström NA detailed geology J.Koskinen, M.Järvinen,T.Karppanen, H.Saarnio, G.Gaál, L.Grundström NA A sample of sulphide-bearing graphite-schist was sent to Outokumpu Oy from the Kotalahti area. Field investigations were started and in September 1954 a sulphide-bearing ultramafic rock was discovered in a roadcut, about 40 km south of the city of Kuopio detailed geophysics J.Koskinen, M.Järvinen,T.Karppanen, H.Saarnio, G.Gaál, L.Grundström NA subsurface exploration J.Koskinen, M.Järvinen,T.Karppanen, H.Saarnio, G.Gaál, L.Grundström Diamond drilling proved that the adjacent magnetic anomaly was caused by a Ni-Cu ore in an ultramafic body. NA 3

4 Mineral Deposit Report Page 4 OF MINING Kotalahti Easting EUREF: ,263 Northing EUREF: ,437 Status: Closed Operating years: Years in production: 31 Total ore mined: t Total production: Product copper nickel Product measure t 82079,62 t Other materials: Material type excavation Material measure t Mining activity: Year Ore mined Ore Activity type Production Other material processed t t underground mining t t underground mining t t underground mining t t borehole mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining nickel 615,71 t copper 228,69 t nickel 2221,57 t copper 851,6 t nickel 2501,6 t copper 926,52 t nickel 3051,32 t copper 1191,92 t nickel 2643,36 t copper 1009,28 t nickel 2316,64 t copper 926,65 t nickel 2543,58 t copper 1036,27 t nickel 3142,23 t copper 1208,55 t nickel 2987,27 t sulphur 0 t copper 1175,32 t nickel 2614,12 t sulphur 0 t copper 998,12 t excavation 0 t excavation 0 t excavation 0 t excavation t excavation t excavation t excavation t excavation t excavation t excavation t 4

5 Mineral Deposit Report Page 5 OF t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining t t underground mining 5 nickel 3510,88 t sulphur 0 t copper 1385,87 t nickel 3780,3 t sulphur 0 t copper 1502,42 t nickel 3125,17 t sulphur 0 t copper 1194,92 t nickel 3057,07 t sulphur 0 t copper 1134,07 t nickel 3020,27 t sulphur 0 t copper 1189,8 t nickel 3149,8 t sulphur 0 t copper 1222,31 t nickel 2930,63 t sulphur 0 t copper 1231,71 t nickel 3370,34 t sulphur 0 t copper 1396,28 t nickel 3277,11 t sulphur 0 t copper 1264,02 t nickel 3526 t sulphur 0 t copper 1294,35 t nickel 3759,37 t sulphur 0 t copper 1512,91 t nickel 3227,23 t copper 1257,36 t nickel 3299,9 t copper 1367,1 t nickel 3543,34 t copper 1426,54 t nickel 3247,39 t copper 1326,4 t nickel 2712,31 t copper 1111,6 t nickel 2218,07 t copper 887,22 t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t excavation t

6 Mineral Deposit Report Page 6 OF t t underground mining t t underground mining t 8119 t underground mining t 0 t underground mining nickel 2357,76 t copper 892,12 t nickel 329,28 t copper 130,08 t excavation t excavation t excavation t excavation t 6

7 Mineral Deposit Report Page 7 OF GEOLOGY Host rock: Peridotite, Pyroxenite, Hornblendite, Amphibolite, Gabbro, Black schist, Metacarbonaterock, Diorite, Calcsilicate-rock, Quartzite Wall rock: Gneiss Peridotite (Host rock) Rock type: Host rock Proportion: present Grain size: Medium grained 2-5 mm Color: NA References: 2, 3, 12 Comments: Lherzolite, Harzburgite and Dunite. Olivine is often moderately serpentinized; orthopyroxene is altered into colourless cummingtonite; clinopyroxene is altered, to a certain extent, into hornblende. Similar lherzolites (coarse-grained and medium-grained) as in Rytky deposit. Ore minerals: Mineral Proportion Mineral texture Argentopentlandite minor Bornite minor In the Jussi orebody Chalcopyrite major Gersdorffite minor Ilmenite minor Mackinawite minor Magnetite minor Millerite minor In the Jussi orebody Pentlandite major Pyrite major In the Jussi orebody. Pyrrhotite major Other minerals: Mineral Proportion Mineral texture Actinolite present Alteration product Anthophyllite present Alteration product Cummingtonite present Alteration product Enstatite present Ni ppm Olivine present Fo 89 mole%, Ni ppm Serpentine present Alteration product Tremolite present Alteration product Structures Folded Alteration: Distribution: Degree: Relation to mineralization: serpentinisation NA NA NA 7

8 Mineral Deposit Report Page 8 OF Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): Paleoproterozoic ( Ma) N Radiometric age: Method: Age: Error (Ma): Mineral: Reference: NA Pyroxenite (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Perknites are pyroxenites that contain amphiboles, some of which may be primary. Most of the perknites, however, have secondary amphiboles and these rocks are obviously alteration products of pyroxenites. The amphibole in perknites is often colourless tremolite or cummingtonite. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Hornblendite (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 8

9 Mineral Deposit Report Page 9 OF Comments: Hornblendites are occasionally encountered in narrow parts of the intrusion where trondhjemitic dykes abound. The major mineral in hornblendites is tschermakitic hornblende with some actinolite. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Amphibolite (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Metamorphosed ultramafic rock, origin unclear. Composed mainly of tremolite, anthophyllite and actinolite. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Gabbro (Host rock) Rock type: Host rock Proportion: present 9

10 Mineral Deposit Report Page 10 OF Grain size: NA Color: NA References: 2, 3, 12 Comments: Includes olivine gabbros, olivine norites, norites, pyroxene gabbros and hornblende gabbros. Poikilitic gabbros contain large grains of plagioclase, several centimeters wide, filled with inclusions of euhedral mafic minerals. The uralitic gabbros and hornblende gabbros in the lower part of the intrusion and elsewhere are frequently ophitic in texture. Structures Folded Textures Poikilitic Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Black schist (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Supracrustal rocks are main host rock for the offset orebody. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Max age - Minage (Ma): Inferred age (Ma): Age of mineralization: 10

11 Mineral Deposit Report Page 11 OF Paleoproterozoic ( Ma) N Metacarbonate-rock (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Supracrustal rocks are main host rock for the offset Jussi orebody. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Diorite (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Max age - Minage (Ma): Inferred age (Ma): Age of mineralization: 11

12 Mineral Deposit Report Page 12 OF Paleoproterozoic ( Ma) N Calcsilicate-rock (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Supracrustal rocks are main host rock for the offset orebody. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Quartzite (Host rock) Rock type: Host rock Proportion: present Grain size: NA Color: NA References: 2, 3, 12 Comments: Supracrustal rocks are main host rock for the offset orebody. Structures Folded Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Max age - Minage (Ma): Inferred age (Ma): Age of mineralization: 12

13 Mineral Deposit Report Page 13 OF Paleoproterozoic ( Ma) N Gneiss (Wall rock) Rock type: Wall rock Proportion: present Grain size: NA Color: NA References: 2, 3, 8, 12 Comments: The wall rocks of the intrusion consist of leucocratic gneisses, which probably are Archaean. Structures Folded Textures Leucocratic Metamorphic description: Type: Facies: Degree: Relation to mineralization: Regional amphibolite high metamorphic NA metamorphic facies grade Comments: Peaked at upper amphibolite facies during D2. Geological age: Min P- Max P (kbar) MIn T- Max T ( C) Geological era: Paleoproterozoic ( Ma) Max age - Minage Inferred age (Ma): Age of mineralization: (Ma): N Figures 13

14 Mineral Deposit Report Page 14 OF ore sample: 14

15 Mineral Deposit Report Page 15 OF Polished section: 15

16 Mineral Deposit Report Page 16 OF Polished section: 16

17 Mineral Deposit Report Page 17 OF XRF analyses; averages for different rock types: 17

18 Mineral Deposit Report Page 18 OF Lithological and structural map of the Kotalahti Dome: 18

19 Mineral Deposit Report Page 19 OF Combined areal gravimetrics and airborne magnetic map: 19

20 Mineral Deposit Report Page 20 OF Olivine compositon on the Ni vs Fo diagram: Whole rock Ni vs MgO: 20

21 Mineral Deposit Report Page 21 OF PGE pattern: 21

22 Mineral Deposit Report Page 22 OF Intrusion plan and cross sections: ore composition: 22

23 Mineral Deposit Report Page 23 OF Harker diagrams: 23

24 Mineral Deposit Report Page 24 OF Lithology of the Kotalahti area: Average whole rock analyses: 24

25 Mineral Deposit Report Page 25 OF

26 Mineral Deposit Report Page 26 OF ore sample: 26

27 Mineral Deposit Report Page 27 OF ore sample: 27

28 Mineral Deposit Report Page 28 OF ore sample: Longitudal section: 28

29 Mineral Deposit Report Page 29 OF Till data values: 29

30 Mineral Deposit Report Page 30 OF REFERENCES 1. Forss, Heikki & Kontoniemi, Olavi & Lempiäinen, Rauli & Luukas, Jouni & Makkonen, Hannu & Mäkinen, Jari Ni-vyöhyke ja 1.9 Ga magmatismi-hankkeen (12204) toiminta vuosina Tervo-Varkaus-alueella. 152 s., 25 liites., Archive report, M 19/3241/99/1/ Gaál, Gabor Geological setting and intrusion tectonics of the Kotalahti nickel-copper deposit, Finland. Bulletin of the Geological Society of Finland 52 (1), Korsman, K. (ed.) & Glebovitsky, V. (ed.) Raahe-Ladoga Zone structure-lithology, metamorphism and metallogeny: a Finnish-Russian cooperation project Map 2: Metamorphism of the Raahe-Ladoga Zone 1: Koskinen, J Geology of the Kotalahti Ni-Cu deposit. In: Häkli, T. A. (ed.) Precambrian ores of Finland : guide to excursions 078 A+C, Part 2 (Finland). Espoo:, Makkonen, H. V Nickel deposits of the 1.88 Ga Kotalahti and Vammala belts. In: Maier, W.D., Lahtinen, R. & O'Brien, H. (eds) Mineral deposits of Finland. Amsterdam: Elsevier, Mäkinen, J. & Makkonen, H.V Petrology and structure of the Palaeoproterozoic (1.9 Ga) Rytky nickel sulphide deposit, central Finland: a comparison with the Kotalahti nickel deposit. Mineralium Deposita 39, Mäkinen, Jari Geochemical characteristics of Svecokarelidic mafic-ultramafic intrusions associated with Ni-Cu occurrences in Finland.. Bulletin p Mäkinen, Jari; Makkonen, Hannu V Petrology and structure of the Palaeoproterozoic (1.9 Ga) Rytky nickel sulphide deposit, central Finland : a comparison with the Kotalahti nickel deposit. Mineralium Deposita 39 (4), Mäkinen, Jari; Makkonen, Hannu; Forss, Heikki Report of investigations of the Rytky nickel occurrence in Leppävirta, claim areas Rytky 2-5 (5629/2, 7081/1, 7227/1, 7318/1), in , Archive report, CM19/3241/2002/2/ Papunen, H Sulphide mineralogy of the Kotalahti and Hitura nickel-copper ores, Finland. Ann. Acad. Sci. Fennicae, Geologica, p. 11. Papunen, H Platinum-group elements in Svecokarelian nickel-copper deposits, Finland. Econ. Geol. 81, Papunen, H.; Koskinen, J Geology of the Kotalahti nickel-copper ore. In: Papunen, H. & Gorbunov, G. I. (eds.) Nickel-copper deposits of the Baltic Shield and Scandinavian Caledonides.. Bulletin 333, Papunen, Heikki Platinum-group elements in metamorphosed Ni-Cu deposits in Finland. In: ed. M. D. Prendergast & M. J. Jones Magmatic sulphides - the Zimbabwe volume. London: The 30

31 Mineral Deposit Report Page 31 OF Institution of Mining and Metallurgy, Papunen, Heikki Ni-Cu sulfide deposits in mafic-ultramafic orogenic intrusions - examples from the Svecofennian areas, Finland. In: Eliopoulos, D. G. et al. (eds.) Mineral exploration and sustainable development : proceedings of the Seventh Biennial SGA Meeting, Athens, Greece, August Vol. 1. Rotterdam: Millpress, Papunen, Heikki; Mäkelä, Markku Sulfur isotopes in Finnish nickel-copper occurrences. Bulletin of the Geological Society of Finland 52 (1), Puustinen, Kauko; Saltikoff, Boris; Tontti, Mikko Distribution and metallogenic types of nickel deposits in Finland.. Report of Ivestigations p. 31