RARE-EARTH ELEMENT (REE) RESOURCES IN NORTHEASTERN CANADA: ADVANCED PROJECTS AND POTENTIAL EXPLORATION ENVIRONMENTS

This presentation reviews major REE deposits in northeastern Canada (Labrador and Québec), with an emphasis on some common geologic parameters and new exploration results. The largest potential resources are at Strange Lake, located on the northern Québec-Labrador border, but there are several other advanced exploration projects in this region, largely associated with Mesoproterozoic peralkaline igneous rocks.

The Strange Lake deposits are hosted by a strongly evolved peralkaline granite ring-complex. Currently-defined resources are associated with near-surface pegmatitic and aplitic zones, with grades of ~ 1% REE oxides + Y₂O₃. This resource includes discrete zones defined in Labrador during the 1980s (~ 57 Mt), and discoveries in Québec since 2008 (~ 114 Mt). Significantly larger, but lower-grade resources occur within enriched host granites in both areas. Strange Lake is relatively enriched in heavy REE, with a typical budget of ~30% Y, ~53% light REE (La to Sm) and ~17% heavy REE (Eu to Lu). Current exploration is mostly in Québec, as adjacent lands in Labrador are excluded pending finalization of a land-use plan with aboriginal groups. In central Labrador, resource estimates are imminent for two diverse styles of REE deposits. Light-REE- and Be-enriched deposits in this area are associated with peralkaline metavolcanic suites, but there is also disseminated eudialyte mineralization associated with coeval undersaturated metaplutonic suites. The eudialyte-rich deposits are enriched in heavy REE, with a typical budget of ~ 25% Y, ~ 54% light REE and ~ 20% heavy REE, but typically depleted in U and Th. At Kipawa in western Québec, some ~10 Mt at ~ 0.6% REE oxides + Y₂O₃) is hosted in deformed peralkaline metaplutonic rocks. This has a typical REE budget of ~22% Y, ~63% light REE and ~15% heavy REE, and is also dominated by eudialyte. Zirconium and niobium are also important in most of these deposits. In northern Québec, the Eldor Project has defined resources of some 117 Mt at 1.74% REE oxides (dominantly light REE), associated with Ta and Nb in a carbonatite intrusion. In addition to these advanced exploration projects, grass-roots exploration for REE and associated elements is presently at record levels in both provinces, with numerous early-stage discoveries that hold potential for future resource definition.