Stratigraphy of the Petiknäs South volcanic-hosted massive sulphide deposit, Skellefte district, Sweden
2004 (English)Conference paper, Presentation (Refereed)
The Petiknäs South VMS deposit in the eastern part of the early Proterozoic Skellefte mining district contained 6 Mt of Zn-Cu-Pb-Au-Ag ore prior to mining. The deposit occurs on the southern limb of a major anticline, dips subvertically, and youngs southwards. The main alteration minerals are sericite, chlorite, quartz, carbonate, talc and carbonate. Two cross sections and one plan section have been constructed on the basis of detailed logging of 35 drill cores, 400 whole-rock analyses and 100 thin sections. Chemostratigraphic units were identified using lithogeochemical techniques. Excluding post-ore andesite sills, the north to south sequence is: feldspar-porphyritic rhyolitic sill; C and B ore lenses hosted by rhyolitic tuffaceous sandstone; andesitic pumiceous mass flows; felsic and intermediate tuffaceous sandstones and siltstones hosting the D and A ore lenses; and a fault followed by rhyodacitic feldspar-quartz porphyry. Prior to andesite sill injection, the C and B ores formed a single massive sulphide lens within a thin interval of rhyolitic volcaniclastic rocks. The D and A ores formed at a stratigraphically higher level, in an interval of alternating rhyolitic and andesitic gravity flow deposits. Weakly altered feldspar-porphyritic rhyolite sills with peperitic margins were then intruded into the felsic volcaniclastic rocks directly below the C+B ore lens. In summary, the two main horizons of ore formation at Petiknäs South are associated with felsic volcaniclastic intervals; coherent felsic rocks occur only as slightly post-ore intrusions. Similar volcanic successions have been recognized elsewhere in the Skellefte district, e.g. at the Renström mine 3 kilometers to the east.
Place, publisher, year, edition, pages
Research subject Ore Geology
IdentifiersURN: urn:nbn:se:ltu:diva-35743Local ID: a668be90-8882-11db-8975-000ea68e967bOAI: oai:DiVA.org:ltu-35743DiVA: diva2:1008997
IAVCEI International Volcanlogic Xongress : Volcanism and its impact on Society 14/11/2004 - 19/11/2004
Godkänd; 2004; 20110603 (ysko)2016-09-302016-09-30Bibliographically approved