TY - JOUR
T1 - Insights into ore genesis of Ni-Cu-PGE sulfide deposits of the Noril'sk Province (Russia)
T2 - evidence from copper and sulfur isotopes
AU - Malitch, Kreshimir N.
AU - Latypov, Rais M.
AU - Badanina, Inna Yu
AU - Sluzhenikin, Sergey F.
PY - 2014/9/1
Y1 - 2014/9/1
N2 - Combined Cu-S isotope data for Ni-Cu-PGE sufides from the economic deposits hosted in the Noril'sk-1, Talnakh and Kharaelakh intrusions, from the subeconomic deposits in the Chernogorsk, Zub-Marksheider, and Vologochan intrusions, and from the non-economic occurrences in the Nizhny Talnakh intrusion in the Noril'sk Province (Russia), and the J-M Reef in the Stillwater Complex (USA), are presented for the first time.Most sulfide samples including the ores from the Talnakh intrusion and the Stillwater Complex have a restricted range of δ65Cu values from -1.1‰ to 0‰, whereas those from the Kharaelakh and Noril'sk-1 intrusions have more variable δ65Cu values of -2.3‰ to 1.0‰. Samples from the three economic deposits in the Noril'sk Province have distinct mean δ65Cu values of -1.56±0.27‰ for Kharaelakh, -0.55±0.41‰ for Talnakh and 0.23±0.28‰ for Noril'sk-1, consistent with those for carbonaceous chondrite and iron meteorites. The variation of δ65Cu values is interpreted to represent a primary signature of the ores, although a magmatic fractionation of Cu isotopes and/or assimilation from an external source cannot be ruled out, particularly in the case of the Kharaelakh ores.Collectively the eight investigated intrusions have an overall sulfur δ34S range from -0.7‰ to 13.8‰. Disseminated and massive ores of the same intrusion have similar δ34S values. The disseminated and massive ores of the Khraelakh intrusion have a mean δ34S value of 12.57±0.54‰ and 12.76±0.42‰, respectively, which are distinctly different from those of the disseminated (10.97±0.44‰) and massive ores (10.88±0.77‰) of the Talnakh intrusion. The different δ34S values of the intrusions may be attributed to sulfur fractionation in deep-seated magma chambers rather than at shallow levels or the present emplacement site. The mean δ34S value of the disseminated ores from the subeconomic Ni-Cu-PGE deposits and non-economic occurrences spans over 10.5‰, averaging 0.39‰ with a standard deviation of 1.55‰ for the highly contaminated Zub-Marksheider rocks, 6.38±1.89‰ for Nizhny Talnakh, 6.90±1.17‰ for Vologochan and 10.86±0.43‰ for Chernogorsk. Samples from the Zub-Marksheider intrusion have mantle-like S isotope signatures, consistent with a deep-seated origin. Although individual mineralized instrusions have a restricted range the overall trend they define of falling δ34S with rising δ65Cu values might be a useful indicator of the economic potential of Ni-Cu-PGE sulfide deposits.
AB - Combined Cu-S isotope data for Ni-Cu-PGE sufides from the economic deposits hosted in the Noril'sk-1, Talnakh and Kharaelakh intrusions, from the subeconomic deposits in the Chernogorsk, Zub-Marksheider, and Vologochan intrusions, and from the non-economic occurrences in the Nizhny Talnakh intrusion in the Noril'sk Province (Russia), and the J-M Reef in the Stillwater Complex (USA), are presented for the first time.Most sulfide samples including the ores from the Talnakh intrusion and the Stillwater Complex have a restricted range of δ65Cu values from -1.1‰ to 0‰, whereas those from the Kharaelakh and Noril'sk-1 intrusions have more variable δ65Cu values of -2.3‰ to 1.0‰. Samples from the three economic deposits in the Noril'sk Province have distinct mean δ65Cu values of -1.56±0.27‰ for Kharaelakh, -0.55±0.41‰ for Talnakh and 0.23±0.28‰ for Noril'sk-1, consistent with those for carbonaceous chondrite and iron meteorites. The variation of δ65Cu values is interpreted to represent a primary signature of the ores, although a magmatic fractionation of Cu isotopes and/or assimilation from an external source cannot be ruled out, particularly in the case of the Kharaelakh ores.Collectively the eight investigated intrusions have an overall sulfur δ34S range from -0.7‰ to 13.8‰. Disseminated and massive ores of the same intrusion have similar δ34S values. The disseminated and massive ores of the Khraelakh intrusion have a mean δ34S value of 12.57±0.54‰ and 12.76±0.42‰, respectively, which are distinctly different from those of the disseminated (10.97±0.44‰) and massive ores (10.88±0.77‰) of the Talnakh intrusion. The different δ34S values of the intrusions may be attributed to sulfur fractionation in deep-seated magma chambers rather than at shallow levels or the present emplacement site. The mean δ34S value of the disseminated ores from the subeconomic Ni-Cu-PGE deposits and non-economic occurrences spans over 10.5‰, averaging 0.39‰ with a standard deviation of 1.55‰ for the highly contaminated Zub-Marksheider rocks, 6.38±1.89‰ for Nizhny Talnakh, 6.90±1.17‰ for Vologochan and 10.86±0.43‰ for Chernogorsk. Samples from the Zub-Marksheider intrusion have mantle-like S isotope signatures, consistent with a deep-seated origin. Although individual mineralized instrusions have a restricted range the overall trend they define of falling δ34S with rising δ65Cu values might be a useful indicator of the economic potential of Ni-Cu-PGE sulfide deposits.
KW - Contamination
KW - Copper and sulfur isotopes
KW - Deep seated origin
KW - Ni-Cu-PGE sulfide deposits
KW - Noril'sk Province
KW - Russia
UR - http://www.scopus.com/inward/record.url?scp=84906792365&partnerID=8YFLogxK
U2 - 10.1016/j.lithos.2014.05.014
DO - 10.1016/j.lithos.2014.05.014
M3 - Article
SN - 0024-4937
VL - 204
SP - 172
EP - 187
JO - Lithos
JF - Lithos
ER -