Remobilization and element redistribution in volcanic-hosted massive sulphide deposits of the Skellefte district, northern Sweden: constraining the role of metamorphic fluid processes

在瑞典北部的Skellefte成矿区内，几个变质火山岩型块状硫化物矿床显示出不同组成的横切脉型矿化，其中最著名的是Au±Bi-Te-Se、AuCu、Au- zn±Pb和Cu类型。这些脉状矿石与块状矿体的成因联系仍存在争议，其中变质再活化和剪切带控制引入是端元概念。Boliden矿床亚硫酸盐-金矿脉的初步研究结果表明，变质再活化作用对这些组合的形成具有重要意义。建议扩大调查范围，纳入全区4个具有代表性的矿床（Kristineberg、Storliden、Renström、Boliden）不同的矿脉和矿石类型，这些矿床经历了不同程度的变形和变质作用。(1) VMS矿床脉状矿化不同类型的矿物学地球化学特征，包括详细的构造和结构研究、电子探针分析、稳定同位素（S、O、H）和流体包裹体分析；(2)重建矿化过程的物理化学条件和计算机辅助热力学模型；(3)建立了脉状矿化形成过程和控制脉状矿化空间分布因素的综合成因模型。

Several of the metamorphosed volcanic-hosted massive sulphide deposits in the Skellefte metallogenic district, northern Sweden, display crosscutting vein-type mineralization of various compositions including most notably Au ± Bi-Te-Se, AuCu, Au-Zn ± Pb, and Cu types. The genetic links between these vein ores and the massive orebodies are still under debate, with metamorphic remobilization and shear zone-controlled introduction being the end-member concepts. The results of preliminary studies of sulphosalt-Au veins from the Boliden deposit indicate the significance of metamorphic remobilization for the formation of these assemblages. It is proposed to expand the investigation to include different vein and ore types from four representative deposits across the district that have been subjected to different degrees of deformation and metamorphism (Kristineberg, Storliden, Renström, Boliden). The study will address the following objectives: (1) Mineralogicalgeochemical characterization of the different styles of veintype mineralization in the VMS deposits, including detailed structural and textural studies, electron-microprobe analysis, stable isotopes (S, O and H) and fluid inclusion analysis; (2) reconstruction of the physico-chemical conditions and computerassisted thermodynamic modelling of the mineralizing processes; (3) development of a comprehensive genetic model that describes both the processes that formed vein-type mineralization and the factors controlling their spatial distribution.