Geology of the Northwest Territories province from dikes and mafic lava flows, overlain by deep ocean turbidite deposits. These rocks are believed to be the remains of oceanic crust that ended up preserved, surrounded on all sides by felsic volcanic rocks and granitoid plutons. In the area of Snofleld Lake in the northern part of the Slave Province, the remains of Archean stromatolites are preserved in a dolomite unit between felsic volcanic and greywacke-mudstone turbidites, some of the earliest evidence of life, forming in the shallows around volcanic islands. Around 1.27 billion years ago in the Proterozoic, a series of major magmatic events affected the
Volcanogenic massive sulfide ore deposit with varying tectonic setting and geological environment during the formation of the VMS. The above groups In the geological past, the majority of VMS deposits were formed in rift environments associated with volcanic rocks. In particular, they formed throughout geological time associated with mid-ocean ridge spreading centres, back-arc spreading centres, and forearc spreading centres. A common theme to all environments of VMS deposits through time is the association with spreading (i.e., an extensional geodynamic regime). The deposits are typically associated with bimodal sequences (sequences with subequal percentages of mafic and felsic rocks - e.g., Noranda or Kuroko), felsic and sediment-rich