This chapter reviews three distinct areas in the Slave craton and assesses their potential of containing ophiolite sequences. The inferred base of the Point Lake volcanic belt is composed of mafic mylonite with low-strain domains of gabbro, pyroxenite, dunite, and peridotite. The mafic mylonite is overlain by gabbro, layered gabbro, minor mafic dikes, pillowed flows, massive flows, hyaloclastite, and local chert. An autochthonous ophiolite sequence overlying basement is possible if crustal ultramafic cumulates, but not the tectonized mantle harzburgite segment are preserved and are part of the ophiolite sequence. Problems of interpretation arise in areas where pillowed and massive flows overlie basement with a depositional contact that has been subsequently transformed into a zone of high strain. East of the mafic mylonite, the most extensive homoclinal sequence in the Peltier Formation is approximately 1.5 km thick. The basalt-dominated sequence is characterized by pillowed and massive flows, pillow breccia, mafic dikes and sills, and minor hyaloclastite and pelagic shale deposits.
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