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Abitibi greenstone belt


The Abitibi greenstone belt is a 2,800-to-2,600-million-year-old greenstone belt that spans across the OntarioQuebec border in Canada. It is mostly made of volcanic rocks, but also includes ultramafic rocks, mafic intrusions, granitoid rocks, and early and middle Precambrian sediments.

The Abitibi greenstone belt is one of the world's largest Archean greenstone belts. It appears to represent a series of thrusted subterranes that exhibit similar geological, geochemical, and isotopical signatures as those formed during the evolution of paired active-arc-back-arc systems. The huge 2,707-to-2,696-million-year-old Blake River Megacaldera Complex is within the belt.



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