VMS deposits occur in a diversity of shapes ranging from flat lens shaped to large sheet-like sulphide mineral rich bodies (Allen, et al., 2002). The preferred environment for these deposits to form in is submarine near a seafloor opening i.e. black smokers, where hydrothermal fluids escape and precipitate on the ocean bottom (Evans & Moon, 2006). The mineralogy of Kidd Creek VMS deposits often consists out of more than 60 different ore minerals and ore-related gangue minerals, of which 90% or more are iron sulphide such as pyrite, pyrrhotite, sphalerite, chalcopyrite and galena. Minerals like bornite, arsenopyrite, tennantite and magnetite may be present in smaller amounts. The gangue is mainly quartz, but occasionally carbonate can also develop
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Rifting causes thinning and extension of the crust, allowing hot magma to rise from deeper crustal levels and precipitates on the ocean floor as metal-bearing hydrothermal deposits. These deposits are often syn-volcanic faults and fissures controlled.
Paragenetic sequence
A concept known as the “reconstructive vein” was created by Emmons (1936). The idea of the reconstructive vein is that the veins extends from the deep crustal levels to the surface and reflects a paragenetic sequence of ore minerals and patterns of zonation.
In VMS deposits there is a development of minerals in a particular order with increasing temperature (Figure 1). The first minerals that are deposited are referred to as “black ore” which includes sphalerite, galena, pyrite and barite at low temperatures (200 - 250°C). The first minerals are replaced by a hotter temperature (300 - 350°C) by minerals such as chalcopyrite (yellow ore). With a further increase in the temperature the copper under saturated solutions dissolve the chalcopyrite to form a base rich in pyrite. During this process, silica and iron rich minerals such as hematite precipitate to forms ferruginous chert (Bulakh and Wenk,
Rifting causes thinning and extension of the crust, allowing hot magma to rise from deeper crustal levels and precipitates on the ocean floor as metal-bearing hydrothermal deposits. These deposits are often syn-volcanic faults and fissures controlled.
Paragenetic sequence
A concept known as the “reconstructive vein” was created by Emmons (1936). The idea of the reconstructive vein is that the veins extends from the deep crustal levels to the surface and reflects a paragenetic sequence of ore minerals and patterns of zonation.
In VMS deposits there is a development of minerals in a particular order with increasing temperature (Figure 1). The first minerals that are deposited are referred to as “black ore” which includes sphalerite, galena, pyrite and barite at low temperatures (200 - 250°C). The first minerals are replaced by a hotter temperature (300 - 350°C) by minerals such as chalcopyrite (yellow ore). With a further increase in the temperature the copper under saturated solutions dissolve the chalcopyrite to form a base rich in pyrite. During this process, silica and iron rich minerals such as hematite precipitate to forms ferruginous chert (Bulakh and Wenk,