Publication Type:Journal Article
Source:Canadian Journal of Earth Sciences = Revue Canadienne des Sciences de la Terre, National Research Council of Canada, Ottawa, ON, Canada, Volume 46, Number 7, p.509-527 (2009)
Keywords:Canada, chemical composition, copper ores, Flin Flon Manitoba, gold ores, hafnium, Hf-177/Hf-176, isotope ratios, Isotopes, Lead, lithologic controls, lithostratigraphy, Manitoba, massive deposits, massive sulfide deposits, metal ores, metals, mineralization, Nd-144/Nd-143, neodymium, Paleoproterozoic, petrography, Precambrian, proterozoic, rare earths, silver ores, Stable isotopes, upper Precambrian, Western Canada, zinc ores
A detailed study of the geochemical and isotopic characteristics of the volcanic rocks of the Hidden and Louis formations, which make up the hanging wall to the volcanogenic massive sulphide deposits at Flin Flon, Manitoba, was carried out on a stratigraphically controlled set of samples. The stratigraphy consists of the lowermost, dominantly basaltic, Hidden formation, and the overlying, dominantly basaltic, Louis formation. Of importance petrogenetically, is the 1920 unit a basaltic andesite with Nb/Th (sub mn) =0.54-0.62, epsilon Nd (sub (1.9 Ga)) =+3.6-+5.9, epsilon Hf (sub (1.9 Ga)) =+8.5-+9.6, and (super 204) Pb/ (super 206) Pb=23.9. The basaltic flows that dominate the Hidden formation have Nb/Th (sub mn) =0.16-0.29, epsilon Nd (sub (1.9 Ga)) =+1.7-+4.4, epsilon Hf (sub (1.9 Ga)) =+7.0-+11.8 and (super 204) Pb/ (super 206) Pb=16.9-18.6). The Carlisle Lake basaltic-andesite (top of Hidden formation) is characterized by Nb/Th (sub mn) =0.16-0.14, and (super 204) Pb/ (super 206) Pb=21.4. The rhyodacitic Tower member (bottom of Louis formation) has Nb/Th (sub mn) =0.23, epsilon Nd (sub 1.9 Ga) =+4.6, epsilon Hf (sub 1.9 Ga) =+9.3, and (super 204) Pb/ (super 206) Pb=22.2. The basaltic flows that dominate the Louis formation have Nb/Th (sub mn) =0.18-0.25, epsilon Nd (sub (1.9 Ga)) =+3.6-+4.2, epsilon Hf (sub (1.9 Ga)) =+8.4-+11.3 and (super 204) Pb/ (super 206) Pb=17.9. The Hidden and Louis formations show dominantly transitional arc tholeiite signatures, with the 1920 unit having arc tholeiite characteristics. It is interpreted to have formed through extensive fractional crystallization of differentiated magmas at shallow levels in oceanic crust. Given the geological, geochemical, and isotopic characteristics of the Hidden and Louis formations, they are interpreted to represent subducted slab metasomatism with minor contamination from subducted sediments.
GeoRef, Copyright 2018, American Geological Institute.<br/>2010-017892<br/>Callinan Deposit<br/>Flin Flon Deposit<br/>Hidden Formation<br/>Louis Formation<br/>Triple 7 Deposit