%A Timo Mäki
%A Marcello Imaña
%A Jukka Kousa
%A Jouni Luukas
%T The Vihanti-Pyhäsalmi VMS Belt
%X The Vihanti-Pyhäsalmi belt contains the most important volcanogenic massive sulfide (VMS) deposits in
Finland. The volcano-sedimentary host rocks belong to a 1.93–1.92 Ga island arc that occurs along the
northwestern parts of the Raahe-Ladoga shear complex. The stratigraphy in the region is divided into two
units, a lower bimodal volcanic unit conforming to the Pyhäsalmi group and an upper volcano-sedimentary
association defined as the Vihanti group. The U-Pb zircon ages of the two groups are similar.
The Vihanti-Pyhäsalmi belt hosts two large VMS deposits, Pyhäsalmi in the Pyhäsalmi group and Vihanti in
the Vihanti group, as well as a number of small sulfide deposits located around them. The Pyhäsalmi
deposit is hosted by rhyolitic and basaltic volcanic rocks, contains 75.7 Mt of pyritic mineralization grading
0.9% Cu, 1.9% Zn, 0.4 g/t Au, and 14.1 g/t Ag, and hosts the only currently producing mine (2014) in the
belt. The Vihanti mine operated from 1954–1992, producing 28 Mt at 5.12% Zn, 0.48% Cu, 0.36% Pb, 25
ppm Ag, and 0.49 ppm Au. The Vihanti deposit and three minor satellite mineralizations are hosted in a
sequence dominated by intermediate and felsic metavolcanic rocks.
%P 507-530
%B Mineral Deposits of Finland
%E Wolfgang Derek Maier
%E Raimo Lahtinen
%E Hugh O'Brian
%V 7
%D 2015
%I Elsevier
%R doi:10.1016/B978-0-12-410438-9.00020-0
%L epos2010