Distribution
The majority of VMS deposits were formed in rift environments associated with volcanic rocks, often associated with mid-ocean ridge spreading centres, back-arc spreading centres, and forearc spreading centres. A theme common to 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 environments (e.g., Bathurst), mafic and sediment-rich environments (e.g., Besshi or Windy Craggy), or mafic-dominated settings (e.g., Cyprus and other ophiolite hosted deposits).
The majority of world deposits are small, with about 80% of known deposits in the range 0.1-10 Mt. Examples of VMS deposits are Kidd Creek in the Abitibi greenstone belt, Ontario, Canada; Flin Flon in the Flin Flon greenstone belt, Manitoba, Canada (777 and Trout Lake Mine); Brunswick #12, New Brunswick, Canada; Rio Tinto, Spain; Greens Creek mine, Alaska, U.S..
Read more about this topic: Volcanogenic Massive Sulfide Ore Deposit
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