Purpose and goal
The project is a unique collaboration between the metal-producing industry (Boliden) and the carbonate-mining industry (Björka Mineral), aiming at improving exploration criteria for polymetallic sulphide deposits (Zn-Pb-Ag) and carbonate deposits (calcite and dolomite). Both are spatially associated with marble units in Bergslagen and some of the best quality industrial carbonate deposits occur in alteration haloes related to nearby sulphide deposits. The main aim of the project is to understand the chemical, mineralogical and isotopic zonation of such alteration haloes.
Structure and implementation
The c. 40 km long marble occurrence in the Sala area will be investigated with emphasis on stratigraphy, structure, lithogeochemistry, stable isotopes and mineralogy. The distribution of mineral deposits will be related back to variations in the marble unit on a regional scale. Detailed studies will be conducted around known sulphide and carbonate occurences in the Sala-Tistbrottet area. Our geochemical and mineralogical data will also be used to investigate the relationship between marble composition and key parameters of interest to the carbonate industry, such as lightness in color
Improved zonation models for marble-hosted mineral deposits will stimulate discoveries of new carbonate and sulphide deposits, in particular at depth where the greatest potential exist. An increased understanding of the alteration systems will allow more accurate and cost-efficient target generation. High-quality carbonate deposits and sulphide deposits commonly occur adjacent to each other. An improved understanding of their relationship may stimulate diversification at existing mines or extend their life-time by adding value to rocks now regarded as waste.