Publication Type:

Book Chapter

Authors:

Tinkham, D. K.; Karlapalem, N.

Source:

Explore in Manitoba; report of activities 2008, Manitoba Geological Survey, Winnipeg, MB, Canada, Volume 2008, p.79-86 (2008)

ISBN:

1498-0010

Keywords:

amphibolite facies, calc-silicate composition, Canada, chemical ratios, facies, geochemistry, Hydrothermal alteration, igneous rocks, lithogeochemistry, lithostratigraphy, Manitoba, massive deposits, massive sulfide deposits, metal ores, Metamorphic rocks, metamorphism, metasomatism, mineral composition, Mineral exploration, Paleoproterozoic, Petrology, Precambrian, proterozoic, protoliths, regional metamorphism, rhyolites, stratigraphic units, upper Precambrian, volcanic rocks, Western Canada

Abstract:

Premetamorphic hydrothermal alteration of Paleo-proterozoic rocks is widespread in the map area and consists of sericite and chlorite alteration of a silica-rich protolith, likely of rhyolitic composition. Carbonate-rich and calcsilicate rocks are interpreted to have developed dominantly from carbonate-altered mafic rocks (basalt or gabbro). Least-altered protoliths of silica-rich rocks are peraluminous, and trace-element chemistry is compatible with that of most silica-rich gneiss that has formed in a volcanic-arc environment. Regional metamorphism in the Sherridon structure reached upper-amphibolite-facies conditions in the sillimanite stability field, as constrained by the occurrence of partial melting in garnet - cordierite - sillimanite - biotite - plagioclase - K-feldspar - quartz stromatic migmatite gneiss. Alteration, lithogeochemical, geochronological and metamorphic studies are in progress to constrain the environment in which volcanogenic massive sulphide deposits of the Sherridon structure formed, and to constrain the metamorphic evolution of the structure.

Notes:

GeoRef, Copyright 2018, American Geological Institute.<br/>2009-064429<br/>Sherridon Manitoba<br/>Sherridon Structure