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TitleThe Boliden gold-rich volcanogenic massive sulfide deposit, Skellefte district, Sweden: new U-Pb age constraints and implications at deposit and district scale
AuthorMercier-Langevin, P; McNicoll, V; Allen, R L; Blight, J H S; Dubé, B
SourceMineralium Deposita vol. 48, issue 4, 2013 p. 485-504,
Alt SeriesEarth Sciences Sector, Contribution Series 20100504
PublisherSpringer Nature
Mediapaper; on-line; digital
File formatpdf
AreaSkellefte; Sweden
Lat/Long WENS 18.4433 20.6275 65.2753 64.8806
Subjectseconomic geology; geochronology; mineral deposits; mineral occurrences; gold; mineralization; volcanogenic deposits; sulphide deposits; sulphides; uranium lead ratios; uranium lead dating; uranium lead dates; Boliden Deposit; Precambrian; Proterozoic
Illustrationslocation maps; photographs; tables; photomicrographs
ProgramTargeted Geoscience Initiative (TGI-4), Volcanogenic Massive Sulfide Ore Systems
ProgramTargeted Geoscience Initiative (TGI-4), Gold Ore Systems
Released2012 10 07
AbstractThe Boliden deposit (8.3 Mt at 15.9 g/t Au) is interpreted to have been formed between ca. 1894 and 1891 Ma, based on two new U-Pb ID-TIMS ages: a maximum age of 1893.9 + 2.0/-1.9 Ma obtained from an altered quartz and feldspar porphyritic rhyolite in the deposit footwall in the volcanic Skellefte group and a minimum age of 1890.8 ± 1 Ma obtained from a felsic mass-flow deposit in the lowermost part of the volcano-sedimentary Vargfors group, which forms the stratigraphic hanging wall to the deposit. These ages are in agreement with the alteration and mineralization being formed at or near the sea floor in the volcanogenic massive sulfide environment. These two ages and the geologic relationships imply that: (1) volcanism and hydrothermal activity in the Skellefte group were initiated earlier than 1.89 Ga which was previously considered to be the onset of volcanism in the Skellefte group; (2) the volcano-sedimentary succession of the Vargfors group is perhaps as old as 1892 Ma in the eastern part of the Skellefte district; and (3) an early (synvolcanic) deformation event in the Skellefte group is evidenced by the unconformity between the ?1893.9 + 2.0/-1.9 Ma Skellefte group upper volcanic rocks and the ?1890.8 ± 1 Ma Vargfors sedimentary and volcanic rocks in the Boliden domain. Differential block tilting, uplift, and subsidence controlled by synvolcanic faults in an extensional environment is likely, perhaps explaining some hybrid VMS-epithermal characteristics shown by the VMS deposits of the district.