Tasiilaq a region unfolds and new findings

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1 Tasiilaq a region unfolds and new findings Regional overview with emphasize on new understanding and mineral potential Bo M. Stensgaard & Jochen Kolb GEUS & MMR SEGMENT participants Greenland Exploration and Opportunities PDAC Toronto - March 2, 2015 Geological Survey of Denmark and Greenland Government of Denmark Ministry of Mineral Resources Government of Greenland

Overall purpose SEGMENT; South-East Greenland Mineral ENdowment Task Jointly financed between GEUS and MMR International research team working towards a better geological understanding in order to

2 Overall purpose SEGMENT; South-East Greenland Mineral ENdowment Task Jointly financed between GEUS and MMR International research team working towards a better geological understanding in order to define the region s mineral endowment Ongoing work; more in 2015/2016 Skjoldungen region to the south, Tasiilaq rgeion to the Northe, SEG Geochemistry Aeromag

Tasiilaq region facts: ~450 km x 120 km Deep fjord-valley

areas Tasiilaq (2064 inhabitants) and 5 smaller

settlements with smaller jetty facilities;

ice-free Kulusuk Airport serviced from Iceland and Nuuk;

3 Tasiilaq region facts: ~450 km x 120 km Deep fjord-valley systems; mountainous and plateaus, accessible coastal areas Tasiilaq (2064 inhabitants) and 5 smaller settlements Larger port facilities in Tasiilaq, settlements with smaller jetty facilities; helistops/-ports in all towns and settlements; 6-8 months ice-free Kulusuk Airport serviced from Iceland and Nuuk; several connections daily in the summer period Local transport by helicopter, smaller boats and skidoos

Limited exploration and survey activities 1960-1970 s 1963 1986 1996

and Grønlands Geologiske Undersøgelse (GGU) Kryolitselskabet Øresund

Diamond Field Int. INCO jv. Diamond Field Int.

4 Limited exploration and survey activities s Reconnaissance work by universities and Grønlands Geologiske Undersøgelse (GGU) Kryolitselskabet Øresund GGU Mapping campaign Nunaoil A/S NunaMinerals A/S PF&U jv. Diamond Field Int. INCO jv. Diamond Field Int./PF&U NunaMinerals A/S GEUS MMR SEGMENT Project 21 st NORTH Aps. New way of scaring away the polar bears

Kolb, 2014 Kolb, 2014 Geological framework: North

north Nagssugtoqidian Orogen (Ammassalik Mobile

1890-1680 Ma, collisional orogen Palaeogene

5 Kolb, 2014 Kolb, 2014 Geological framework: North Atlantic Craton to the south Rae Craton to the north Nagssugtoqidian Orogen (Ammassalik Mobile Belt), ca Ma, collisional orogen Palaeogene Magmatism related to the North Atlantic ocean break-up; 60 Ma Tectonic situation at subduction collision

60 km AIC Isortoq Terrane Thrym Complex Palaeogene Schweizerland Terrane Kuummiut Terrane Unknown successions? Thrym Complex: to the south, polyphase Archaean 3.

6 60 km AIC Isortoq Terrane Thrym Complex Palaeogene Schweizerland Terrane Kuummiut Terrane Unknown successions? Thrym Complex: to the south, polyphase Archaean 3.0 Ga orthogneiss, towards the north deformed during the Paleoproterozoic; include mafic granulite part of North Atlantic Craton Isortoq Terrane: Archaean gneiss, amphibolite and ultramafics deformed by the Nagssugtoqidian orogen Ammassalik Intrusive Complex (AIC): noritediorite-gabbro complex, anatectic gneisssupracrustals, and post-tectonic granite and dolerite Kuummiut Terrane: Archaean Ga migmatitic orthogneiss, Palaeoproterozoic metasediments (marble, quartzite, garnet-graphiteschist, meta-psammite and meta-pelite) and amphibolite. Complex metamorphic history; include widespread eclogite-facies assemblages. Part of the Rae Craton. Schweizerland Terrane: brown Archaean Ga orthogneiss, Niflheim Thrust. Part of the Rae Craton. Palaeogene province: alkaline and mafic intrusives and basalts related to the opening of the North Atlantic Ocean

New discovery Køge Bugt succession New succession in the Thrym Complex and Isortoq Terranes; discovered during fieldwork in 2014 Flat-lying mylonitic paragneiss and

S-vergent as would be expected from the Nagssugtoqidian further north Older than Nagssugtiqidian deformed towards north 60 km AIC Palaeogene Schweizerland Terrane

7 New discovery Køge Bugt succession New succession in the Thrym Complex and Isortoq Terranes; discovered during fieldwork in 2014 Flat-lying mylonitic paragneiss and marble sandwiched between orthogneiss in footwall and hanging wall; unknown age; greenschist facies All major brittle ductile to ductile shearing is SEvergent, not S-vergent as would be expected from the Nagssugtoqidian further north Older than Nagssugtiqidian deformed towards north 60 km AIC Palaeogene Schweizerland Terrane Kuummiut Terrane Isortoq Terrane Unknown new succession? Thrym Complex Paragneiss thrust on top of orthogneiss and amphibolite Preserved bedding in meta-sedimentary unit

8 New discovery Køge Bugt succession Harsh area, very limited work and exploration; mineral potential unknown 60 km AIC Kuummut Terrane Unknown new terrane? Palaeogene Schweizerland Terrane Isortoq Terrane Thrym complex Meta-graywacke Banded paragneiss Quartzite Mylonitic shear zone

60 km 1 2 1 3 4 6 3 5 AIC Isortoq Terrane Palaeogene Schweizerland Terrane Kuummut Terrane Several phases of intrusive activity: 1. Archaean meta-anorthosite/leucogabbro 2. Archaean (2.2 Ga?

9 60 km AIC Isortoq Terrane Palaeogene Schweizerland Terrane Kuummut Terrane Several phases of intrusive activity: 1. Archaean meta-anorthosite/leucogabbro 2. Archaean (2.2 Ga?) diorite-tonalite 3. Archaean ultramafic complexes 4. Palaeoproterozoic (1.85 Ga) AIC norite, gabbro, diorite, granodiorite complex 5. Palaeoproterozoic (1.7 Ga) granite, granodiorite, diorite, gabbro complex 6. Palaeogene intrusions: Ma; alkaline to mafic intrusions Thrym complex

10 ~ Niflheim Thrust

11 Ammassalik Intrusive Complex: Diorite of ~1885 Ma Contact metamorphic aureole

12 Supracrustals in the AIC contact aureole

13 Mineral potential within the East Greenland Nagssugtoqidian Orogen, Tasiilaq some of the findings from 2014

rocks in the anatectic supracrustal zone

from 1 to 8 m Ni up to 1.39%, Cu up to 0.

14 Ni-Cu-PGE potential in AIC? Earlier discoveries by NunaOil A/S of Ni-Cu-PGE semi-massive sulphidemineralisation within ultramafic rocks in the anatectic supracrustal zone outside the AIC; komatiite-nickel exploration model m on surface and varies in width from 1 to 8 m Ni up to 1.39%, Cu up to 0.5% Ni Tenor 4.72%, Cu Tenor 1.56% Fieldwork 2014: Orthomagmatic conduit-type exploration model New discovery of semi-massive sulphide mineralisation within gabbro-norite-tonalite of the AIC A. A.

2014 discovery within the AIC 8 m wide, 20-30 m long steeply dipping mineralised zone hosted by a fine-grained darkgrey Qtz-Plag-Bt-Mgt rock within gabbro of the AIC Pyrrhotite, pyrite, chalcopyrite

magmatic stage A orthomagmatic sulphide-mineralising system is present within the AIC; either zoned ore body, hydrothermal remobilised or barren?

15 2014 discovery within the AIC 8 m wide, m long steeply dipping mineralised zone hosted by a fine-grained darkgrey Qtz-Plag-Bt-Mgt rock within gabbro of the AIC Pyrrhotite, pyrite, chalcopyrite present; no olivine Semi-massive to disseminated sulphides elevated in Ni (up to 280), Cu (up to 150 ppb) and Au (up to 240 ppb); orthomagmatic textures, hydrothermal remobilisation, late in the magmatic stage A orthomagmatic sulphide-mineralising system is present within the AIC; either zoned ore body, hydrothermal remobilised or barren? Other similar occurrences found within the AIC; but limited follow-up Further work is needed to follow-up on this mineralisation type within the AIC Note; Cu-Ni-PGE anomalous samples have also been collected within the AIC at Tasiilaq and Kulusuk granodiorite granodiorite 2014 discovery outcrop

16 prh cpy gra

Gold potential Former exploration results Ujarassiorit results

geochemistry GEUS-MMR Au>1ppm fieldwork 1.1 ppm 15.2 ppm Qtz w.

pyrite 2 ppm MMR-GEUS Stream Sediment Geochemistry 2010 11.

5 ppm Amphibolite 14.7 ppm 20 ppm Qz-vein 2.

17 Gold potential Former exploration results Ujarassiorit results SEGMENT Geochemistry ppb Au in stream sediment geochemistry GEUS-MMR Au>1ppm fieldwork 1.1 ppm 15.2 ppm Qtz w. pyrite 10.6 ppm Qtz w. pyrite 2 ppm MMR-GEUS Stream Sediment Geochemistry ppm Graphitegarnet-gneiss 1.1 ppm 5.2 ppm Amphiibolite 7.5 ppm Amphibolite 14.7 ppm 20 ppm Qz-vein 2.5 ppm 40 km Ujarassiorit results , Au above 50 ppb with indications of those above 1 ppm Au (both float and bedrock; locations uncertain)

Gold potential - 2014 Fieldwork confirmed occurrences of anomalous gold within quartz-veins at Auppaluttoq; however, other anomalous areas (floats) were not confirmed.

18 Gold potential Fieldwork confirmed occurrences of anomalous gold within quartz-veins at Auppaluttoq; however, other anomalous areas (floats) were not confirmed. More possible targets are present A GEUS-MMR targeting exercise is ongoing Gold seems to be hosted in quartzvein systems within supracrustal sequences; these are very weathered and appear as rusty-gossans. A gold potential is present; but more detailed field campaigns are wanted e.g. detailed large rock and soil-sampling program investigations of weathering; leaching of metals under Arctic conditions The local Ujarassiorit 1 st prize winner William Umerineq at the Auppaluttoq site where he sample gave 11 g/t Au. GEUS-MMR were not able to replicate this; but picked-up 0.5 g/t Au in quartz-veins from the site. Nugget-effects may be causing this and only limited work have been carried out on the site.

areas have been studied in detail, Auppaluttoq and two at Kangikajik (<30 wt.

19 Rosing-Schow et al Graphite potential Graphite within meta-pelite/-schist units within the supracrustal is widespread Within certain horizons and structural controlled zones these approach ore grade Two areas have been studied in detail, Auppaluttoq and two at Kangikajik (<30 wt.% graphitic carbon) uninvestigated graphite occurrences are present in between Strong supergene alteration; loose limonite gravel, which contains graphite flakes as a main component. One area being km. Flakes up to 6 mm; average of 3.33 mm ± 1.21 mm Most likely hydrothermal deposited graphite Rosing-Schow et al Supergene limonite alteration zone in central Auppaluttoq. The zone is approximately 300 m wide and surrounded by orthogneiss.

Ruby-sapphire potential Follow-up on Ujarassiorit winning ruby sample revealed several ruby occurrences in the area share the same characteristics: rubysapphire occurs where late-stage felsic

20 Ruby-sapphire potential Follow-up on Ujarassiorit winning ruby sample revealed several ruby occurrences in the area share the same characteristics: rubysapphire occurs where late-stage felsic pegmatites crosscut and metasomatically interact with metamorphosed ultramafic rocks. A progressive metasomatic replacement of the pegmatite takes place with welldeveloped mineral zoning, culminating in a biotite zone, followed by a zone with black amphibole + pink to purple rubysapphire. Ruby-sapphire is rare, but large (locally up to 5 cm in diameter), anhedral in shape with only little fractures. Metasomatic reaction band in ultramafic rock with concentric mineral zones; core zone consists of pure biotite, locally enveloping a black amphibole + purple ruby zone. The genetic model works; new discoveries made, however more work is needed; potential for larger systems?

Mineral potential within the East Greenland Nagssugtoqidian Orogen, Tasiilaq Other possibilities (which I have not talked about today) Ni-Cu-PGE potential within other Archaean,

21 Mineral potential within the East Greenland Nagssugtoqidian Orogen, Tasiilaq Other possibilities (which I have not talked about today) Ni-Cu-PGE potential within other Archaean, Palaeoproterozoic and Palaeogene intrusives in the region Cu-Au-Zn potential within Archaean(?) and Palaeoproterozoic volcanics Palaeogene rhyolite with semi-massive sulphide Au-Cu potential?

Overall purpose SEGMENT; South-East Greenland Mineral ENdowment Task An interesting geological model unfolds for entire South East Greenland The Tasiilaq and, perhaps to a lesser

endowment report and a digital GIS data package to be presented early 2016 A final workshop including summary of new model and data will be announced in 2016 Stream sediment

22 Overall purpose SEGMENT; South-East Greenland Mineral ENdowment Task An interesting geological model unfolds for entire South East Greenland The Tasiilaq and, perhaps to a lesser extend the Skjoldungen region comprise a potential for different mineral resources The ongoing work by GEUS and MMR will continue in 2015 with more results pending Final mineral endowment report and a digital GIS data package to be presented early 2016 A final workshop including summary of new model and data will be announced in 2016 Stream sediment geochemistry and indicator mineral data as well as new regional aeromagnetic data are already available No licenses are currently claimed in the region; interested in knowing more come and visit us

23 Visit us at booth number 417 Thank you For more information, please contact Bo M. Stensgaard

24 the end...

New Understanding and mineral endowment of the Archaean, Palaeoproterozoic and Palaeogene of South-East Greenland

Greenland Day Perth, Dec. 9 th, 2015 New Understanding and mineral endowment of the Archaean, Palaeoproterozoic and Palaeogene of South-East Greenland Bo M. Stensgaard & Jochen Kolb Department of Petrology