Petrogenesis and Tectonic Setting of Mafic Meta-igneous Rocks from Hope Bay and Elu Greenstone Belts, NE Slave

Summary In the northeastern part of the Slave Craton (Bathurst Block), the NE-striking Elu Belt (EB) is linked to the adjacent N-striking Hope Bay Belt (HBB) by an arcuate E-W connection zone termed the Elu Link (EL). The EL provides new insights into key geological relationships in the ca. 2700-2600 Ma EB and HBB. A preliminary geochemical study of mafic meta-igneous rocks from EL and HB belts shows they are similar and represent tholeiitic to calc-alkaline basalts and basaltic andesites. These rocks represent three magmatic suites, mainly Ti-depleted flat REE, Ti-enriched flat REE, and Ti+LREE enriched magmatic systems. Like mafic rocks in the Yellowknife belt, rocks in the EL and HBB are inferred to have derived from deep to shallow mantle sources and emplaced in a back-arc setting over attenuated continental crust.

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