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Geologists brave Canada's last frontier

CNGO leads project aimed at filling in geological blanks on Hall Peninsula maps; tallies multi-program accomplishments in 2011

David Mate, chief geologist for the Canada Nunavut Geoscience Office, is part of a team of scientists venturing this field season into relatively unknown territory.

Mate refers to the Hall Peninsula where he will be working this summer as "white space" on modern geological maps.

"This is very exciting for a geologist. It's also interesting because it's in my backyard," Mate told Mining News April 22.

Nunavut is Canada's northernmost and least-explored territory. About 1 ½ times the size of Alaska it is generally regarded as a vast Arctic treasure trove of untapped mineral resources. The Hall Peninsula is a relatively accessible chunk of real estate that lies between Frobisher Bay and Cumberland Sound just to the north of Nunavut's capital city, Iqaluit.

The purpose of the multiyear Hall Peninsula Integrated Geoscience Program is to use geoscience to help contribute to a better understanding of the land in this underexplored region. The work is important because Hall Peninsula is an area in Nunavut that has never been mapped or studied to modern geologic standards.

In general, geologists agree that only about one-third of Nunavut has been adequately mapped to modern geological standards. Compare that with Alaska where adequate geological mapping has been conducted over roughly one-half of the state, geologists say.

"We still have large tracts of the territory that don't have adequate geological information. There are not many places left in Canada, or the world for that matter, that you can say this about," said Mate. "It is a geological frontier up here."

CNGO, a partnership between Natural Resources Canada, Aboriginal Affairs and Northern Development Canada, and the Government of Nunavut's Department of Economic Development and Transportation, was established when Nunavut became Canada's newest territory in 1999. The small office of seven geologists have a big job, providing geoscience information and expertise that supports responsible resource exploration and development, education and training, and geoscience awareness and outreach, according to its mission statement.

CNGO concentrates on new geoscience mapping and research, supporting geoscience capacity building, disseminating geoscience information and developing collaborative partnerships of strategic importance to Nunavut.

The Hall Peninsula project is being led by CNGO in collaboration with partners from universities, industry and federal and territorial governments. Mate, who took the helm at CNGO in September, will be joined by other key scientists on the project, including Gabriel Machado, Tommy Tremblay, Rosemarie Khoun and Shunxin Zhang of CNGO and Martin Ross and Cassia Johnson of the University of Waterloo.

"I've heard it said that often the geology closest to camp is the last to get studied," Mate said. "That's the case with the Hall Peninsula."

The study area comprises all or parts of nine National Topographic Scale (scale 1:250,000) map sheets north and east of Iqaluit with the most intensive efforts to be conducted in NTS map sheets 25O and 26B.

The team conducted reconnaissance field work during the summer of 2011, and field mapping is planned for 2012 and 2013 with activities to include regional bedrock mapping, an assessment of mineral potential and regional tectonics, mapping and sampling of surficial materials, and permafrost and terrain stability research.

This work builds on masters-level research conducted at the University of Waterloo on subglacial erosion, transportation, and deposition on northeastern Hall Peninsula.

It includes detailed mapping, collection of meso- and micro-scale ice flow indicators, and understanding glacial erosion intensity using cosmogenic dating.

CNGO says such a comprehensive approach to drift prospecting has rarely been applied in the Canadian Arctic.

These types of geoscience products can help decision-makers in Nunavut and industry determine what minerals (e.g. gold, base metals, etc.), carving and gemstone resources are in the area as well as provide information on terrain sensitivity and climate change adaptation.

The research will be conducted from a camp on the land. The camp will consist of up to 20-25 scientists and support staff and it will be supported by two helicopters. Geologists will be dropped off daily at different places on the land where they will conduct foot traverses to study the rocks and soil as they walk. They will record their observations in handheld computers and download this information every night back at camp into a central database. This digital data can be manipulated and used to make maps. The geologists also will take small rock samples (fist-size) so they can analyze them in a lab to determine such characteristics as their age and chemical makeup.

Mate said he believes the C$1.5 million mapping program will be very rewarding because it will help close the knowledge gap in ways that will provide particularly useful geological information to government, industry and community decision-makers in Nunavut.

"Results from the project will greatly enhance Nunavut's understanding of its own land," he said.

Peregrine Diamonds Ltd. has been exploring the Hall Peninsula for diamonds for at least six years, including ongoing work at its highly prospective Chidliak Project where it has discovered 59 kimberlites so far, many of which are considered diamondiferous.

The junior April 11 reported the start of a C $10 million exploration program for 2012 that will consist primarily of advance preparations for a bulk sampling program in 2013, along with significant exploration this summer to discover more diamondiferous kimberlites.

Discussing the mapping program, Peregrine Diamonds Chief Geoscientist Jennifer Pell, Ph.D., said "Peregrine Diamonds is actively exploring for diamonds and other metals on Hall Peninsula, and is very supportive of the Canada-Nunavut Geoscience Office's 2012 mapping program there.

Bedrock mapping gives the industry key information on the rock formations which can help increase the understanding of the deposit types that may be present and assist with interpreting airborne geophysical survey results.

The mapping of the surface sediments in the area also adds to our understanding of glacial history, which is key to indicator mineral interpretation which is critical for diamond exploration."

More geoscience work

Development of Nunavut's mineral and energy resources and the infrastructure required to service the territory and its communities, form an important foundation for the territory's economy.

Mate said his office conducted studies in 2011 that investigated the territory's sand and gravel and carving stone resources, examined geological factors related infrastructure and the effects of permafrost and coastal sea levels in Canada's North.

"We recently published community-scale geology maps for infrastructure planning. That is new up here and we're pretty proud of that," he said.

Yet there is much more work to be done in Nunavut. "We're always open to hearing new ideas and needs and new research priorities, whether they come from the community, industry or government decision makers," the geologist said.

CNGO and its partners worked with the federal Geo-mapping for Energy and Minerals program to conduct a number of other programs in 2011, including some with multiyear components like the Hall Peninsula study. Among the programs:

• Nunavut Aggregate Resource Mapping and Assessment: Serge Basso and David Mate of CNGO and Roy Green and Bu Lam of the Government of Nunavut led this effort. Sufficient quantity and variety of high-quality granular material provides the basis for infrastructure development and the economic well-being of every community in Nunavut.

Aggregate resources (sand and gravel) are used for the construction of roads and air strips, but also for gravel pads that insulate underlying permafrost and provide erosion control features to buildings and other infrastructure.

The multiyear project is focused on locating, mapping and describing aggregate resources near communities in some 40 reports to create an inventory to assist development in the territory.

In 2011, the focus of the project was on the development of Nunavut's first aggregate resource database.

This involved developing a web application accessible through http://www.nunavutgeoscience.ca that will enable users to browse, download and submit aggregate resource reports and maps.

Such a tool will benefit community and infrastructure development in the territory and help focus work on identifying new aggregate resources.

• Iqaluit Permafrost and Terrain Study: Anne-Marie Leblanc of the GSC; Naomi Short of Canada Centre for Remote Sensing); Michel Allard of Université Laval; and David Mate of CNGO collaborated on this project.

The city of Iqaluit is growing rapidly and consists of key strategic infrastructure including its airport, which is the gateway to the eastern Canadian Arctic.

The city and its infrastructure are underlain by continuous permafrost that is now warming and thawing in places.

In order to reduce the risk to investments in northern resource development that these changes pose, this joint CNGO, Université Laval and NRCan (GSC and Canada Centre for Remote Sensing) study on the sensitivity of permafrost and terrain conditions within the city began in 2010.

Recent results have demonstrated a clear link between original terrain units, permafrost features and the problems currently affecting infrastructure.

Surficial geological mapping of the Iqaluit airport shows that it was built over a dense network of ice wedge polygons and that pre-existing lakes and streams were filled to build embankments for the runway, taxiways and apron.

Many of the permafrost-related problems that exist can be linked to these pre-construction features.

• Satellite interferometric synthetic aperture radar observations were collected over Iqaluit and the airport to detect ground displacements and assess terrain stability.

These observations correlate very well with the mapped terrain units.

Stable ground occurs in areas underlain by bedrock and till (e.g.

the Plateau subdivision) whereas areas with differential thaw settlement are visible in older parts of the city that are built on old glaciomarine sands and silts.

Since 2010, several permafrost temperature monitoring sites have been installed in the urban area, at the airport, and in natural, undisturbed landscapes to characterize ground thermal regimes and measure thaw settlements.

Results from this integrated work will help government, community and industry stakeholders better understand landscape constraints for building infrastructure.

Kimberlite Indicator Information for Nunavut: Rosemarie Khoun of CNGO and Aleksandar Miskovic of Aboriginal Affairs and Northern Development Canada - Northwest Territories Office led a data dissemination effort in which information about new kimberlite indicator information for Nunavut was made available to assist exploration companies and advance Northern economic development. The Kimberlite Indicator Database (KIDD) and Kimberlite Indicator

• Chemistry Database (KIMC) for Nunavut can now be accessed through the NTGO website (www.nwtgeoscience.ca). KIDD information has been gathered from assessment reports containing kimberlite indicator mineral data, including the sample location and the counts of visually picked mineral grains. The searchable Nunavut KIDD database currently contains 70,711 records. The KIMC database is an extension of the KIDD database, consisting of mineral chemistry from electron-microprobe analysis of select kimberlite indicator minerals. A total of 1,726 KIMC laboratory records for Nunavut can now be accessed.

• Elu Greenstone Belt, Northeast Slave Province: Hubert Mvondo and Dave Lentz of the University of New Brunswick led a mapping project in collaboration with Newmont Mining Corp. and CNGO. Hope Bay and Elu are two stratigraphically and structurally connected Neoarchean (ca.

2,800 to 2,500 million year-old (Ma)) greenstone belts in the NE Slave Craton.

The Boston gold deposit, located at the intersection of the two belts, is bounded to the east by a migmatitic granitoid complex.

The Boston mapping project studied the timing between mineralization and tectonic evolution in the area east of the deposit.

The mineralization occurs principally near the contact between intrusions and their host rocks and relates to shear zones.

Noticeable sulphide occurrences in mafic xenoliths show that they could represent reliable indicators for exploration.

Sulphide-rich veining occurs also along faults.

New mapping indicates that Neoarchean to Proterozoic hydrothermal activity and metal remobilization occurred extensively east of the Boston gold deposit.

• Borden Basin, Multiple Metals: Elizabeth Turner and Katie Hahn of Laurentian University led the Borden Basin project, a multi-year effort aimed at providing a modern understanding of the tectonostratigraphic evolution and economic potential of Mesoproterozoic sedimentary basins of northeastern Nunavut for renewed exploration in an area of historic mining activity (Nanisivik district).

With support from the Polar Continental Shelf Project, field activity in 2011 focused on the very large deep-water carbonate mounds of the Ikpiarjuk Formation.

These mounds are hundreds of meters thick and kilometers wide in diameter and are associated with the upper Arctic Bay Formation of black shale and syndepositional faults.

A new Ph.D. student and assistant team spent five weeks mapping and establishing the stratigraphic context and depositional environments for two of the seven known mounds.

Additional work is being conducted to understand the timing of mineralization and provide insight on the temperature and composition of mineralizing fluids at Nanisivik.

Publication output included: a paper in Economic Geology that addresses spatial controls on the distribution of known carbonate-hosted base-metal showings in the Borden Basin based on stratigraphic and structural mapping; submission of a paper to Precambrian Research describing the results of a study on base-metal potential of black shale in the Arctic Bay Formation; and a journal paper on uranium potential at the base of the Mesoproterozoic successions has been accepted in Precambrian Research.

• Cumberland Peninsula Project - GEM: Mary Sanborn-Barrie of the Geological Survey of Canada and Mike Young of Dalhousie University focused on the Cumberland Peninsula project, which is providing new geoscience knowledge for underexplored eastern Baffin Island.

This advanced stage GEM project has acquired and released more than 62,000 line-kilometers of high resolution aeromagnetic data (GSC Open Files 6086-6103), completed regional 1:100,000 scale surficial and bedrock mapping (2009 to 2010), and gained regional geochemical, geochronological, structural and assay data (2009 to 2011).

Collectively, new geologic knowledge has stimulated mineral exploration in the project area, provides relevant public geoscience information, and is resolving questions regarding Cumberland Peninsula's economic potential.

It is now recognized that an ancient 2.8 billion to 3.0 billion-year-old tonalitic basement underlies about half of Cumberland Peninsula.

Tectonically juxtaposed with the basement are 1.95 billion to 1.9 billion-year-old cover rocks of the Paleoproterozoic Hoare Bay group and a potentially upper, rift-related sequence of chert, graphitic schist, iron formation and mafic and ultramafic volcanic rocks.

Elevated concentrations of multiple metals in the metavolcanic assemblage present an exploration target for copper-nickel-gold.

A 200-kilometer (124 miles) long belt of 1.89 billion-year-old granitic rocks, which form the topographically spectacular mountains showcased in Auyuittuq National Park, is intrusive into both basement and cover rocks.

Project activities in 2011 focused on completion of all bedrock and surficial maps, acquisition of strategic value-added data, and targeted mapping of the northeastern volcanic-bearing corridor.

To this end, three new 1:100,000-scale bedrock geology maps of southern Cumberland Peninsula, released in June 2011 (GSC Canadian Geoscience Map (CGM) 1-3) and six surficial maps released in October 2011 (GSC CGM 15-20), provided guidance to ongoing mine

 

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