Structural controls and associated alterations in the West Maurliden volcanic-hosted massive sulfide deposit, Skellefte district, northern Sweden

Sammanfattning: Volcanic-hosted massive sulfide (VMS) deposits are one of the main sources for zinc, copper, lead, silver and gold in Sweden. The majority of VMS deposits in Sweden are located in the Bergslagen region and the Skellefte district (Fig. 1). The Skellefte district hosts approximately 80 VMS deposits whereas 21 deposits have been mined since 1924 and 6 mines are currently in operation. VMS deposits tend to form more often on the intersection of the normal/reverse and transfer faults since there is an increased conductivity for hydrothermal fluids and increased fluid flow, so a structural interpretation of regional and deposit scale is important for exploration. The alteration patterns and mapped structures observed in the West Maurliden coincide with major structures found in the Skellefte district. Using this data and data from previous authors a general structural evolution of the Maurliden deposit has been constructed which shows the presumed outcome from the early extensional and later compressional stages ongoing in the region. Study of the mineralization shows that there is also the possibility to find mineralized rock within possible low strain blocks which might contain preserved primary textures and structures. A schematic plan view of the structure assemblage in the Skellefte district was established which shows perspective areas for future exploration.