FN Archimer Export Format
PT J
TI Nickel isotope fractionation in komatiites and associated sulfides in the hart deposit, Late Archean Abitibi Greenstone Belt, Canada
BT 
AF Hiebert, R.S.
   Bekker, A.
   Houlé, M.G.
   Rouxel, Olivier
AS 1:1;2:1,2,3;3:4;4:5;
FF 1:;2:;3:;4:PDG-REM-GEOOCEAN;
C1 Department of Geological Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
   Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521, USA
   Department of Geology, University of Johannesburg, Auckland Park, Johannesburg 2006, South Africa
   Geological Survey of Canada, Lands and Minerals Sector, Natural Resources Canada, Québec, QC G1K 9A9, Canada
   IFREMER, Centre de Brest, Unité Géosciences Marines, F-29280 Plouzané, France
C2 UNIV MANITOBA, CANADA
   UNIV CALIF RIVERSIDE, USA
   UNIV JOHANNESBURG, SOUTH AFRICA
   GEOL SURVEY CANADA, CANADA
   IFREMER, FRANCE
SI BREST
SE PDG-REM-GEOOCEAN
UM GEO-OCEAN
IN WOS Ifremer UMR
   copubli-int-hors-europe
   copubli-sud
IF 3.9
TC 3
UR https://archimer.ifremer.fr/doc/00771/88266/93954.pdf
LA English
DT Article
DE ;Nickel;Stable isotope;Komatiite;Nickel isotope
AB Extremely light and highly variable δ60Ni values have been observed in komatiite-associated magmatic sulfides in recent studies. In this study, we examine the mechanisms of Ni isotope fractionation between silicate and sulfide liquids in the Hart komatiite-associated Fe-Ni-Cu-sulfide system. We assess the petrogenetic significance of these mechanisms using Ni isotope and concentration data. The concentration of Ni in bulk rock varies from 774 to 2690 ppm in komatiite samples with no sulfide minerals to 8380–39,300 ppm in samples almost entirely consisting of sulfide minerals. The δ60Ni values vary from +0.14‰ in komatiite samples with no sulfide minerals to −1.06‰ in samples dominantly consisting of sulfide minerals. A theoretical model of fractionation between the komatiitic lava and sulfide xenomelt with nickel isotope exchange followed by fractional crystallization during crystallization of the sulfide melt can produce a range of δ60Ni values from +0.17‰ to −1.02‰ in sulfide-rich rocks depending on the extent of fractional crystallization and the amount of trapped melt between the sulfide mineral grains, which corresponds well with the range of values observed in these rocks. This proposed model requires fractionation of Ni isotopes between sulfide liquid and the earliest formed sulfide crystals during crystallization. Effects of later crystallization during peritectic reactions and subsolidus exsolution could be tested by in situ measurements of Ni isotopes in different textural varieties of pentlandite that formed over a large range of temperatures during cooling. 
PY 2022
PD AUG
SO Chemical Geology
SN 0009-2541
PU Elsevier BV
VL 603
UT 000806779200007
DI 10.1016/j.chemgeo.2022.120912
ID 88266
ER

EF