Re-Os dating of chalcopyrite from selected mineral deposits in the Kalatag district in the eastern Tianshan Orogen, China

X.H. Deng, J.B. Wang, Franco Pirajno, Y.W. Wang, Y.C. Li, C. Li, L.M. Zhou, Y.J. Chen

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

© 2016 Elsevier B.V. The Kalatag Cu-Zn-Au district contains a number of economically important Cu deposits in eastern Tianshan in Xinjiang, NW China. Due to the lack of precise mineralization ages, the metallogenesis of this area has long been a matter of debate. In this study, chalcopyrite Re-Os isotope methods are used to date the South Meiling Cu-Zn and Hongshi Cu deposits in the eastern part of Kalatag area.The South Meiling Cu-Zn deposit is hosted in volcanic-sedimentary rocks of the Late Ordovician to Early Silurian Daliugou Formation. The deposit consists of two parts: a concordant massive sulfide ores and discordant vein-type ores located in the footwall strata. The principal ore minerals are pyrite, chalcopyrite, sphalerite, minor tetrahedrite, galena and pyrrhotite. Gangue minerals include quartz, sericite and barite, and minor chlorite, plagioclase and carbonate minerals. The Hongshi Cu deposit represents a hydrothermal vein system hosted in the mafic volcanic rocks of Daliugou Formation. The orebodies are associated with quartz veins and controlled by subsidiary faults of the Kalatag fault. The ore-forming process can be divided into the early, middle and late stages and is characterized by quartz-pyrite, quartz-chalcopyrite-pyrite and quartz-carbonate-gypsum veins, respectively.Re-Os analyses of chalcopyrite from the South Meiling Cu-Zn deposit yield an isochron age of 434.2 ± 3.9 Ma and initial 187Os/188Os ratio of 0.647 ± 0.098 (MSWD = 0.59). Re-Os analyses of chalcopyrite from the Hongshi Cu deposit yield an isochron age of 431.8 ± 2.7 Ma and initial 187Os/188Os ratio of -0.165 ± 0.075 (MSWD = 0.77). Since chalcopyrite is the primary copper mineral, we interpret these isochron ages as the timing of Cu mineralization, based on field geology and petrographic evidence. These results suggest that the Re-Os ages presented here provide, for the first time, a direct constraint on an early Paleozoic Cu mineralization event of the eastern Tianshan Orogen. The high initial 187Os/188Os ratios (0.647 ± 0.098) ratio of ~434 Ma chalcopyrite from the South Meiling deposit suggest that the metal was sourced from a two end-member mixing of crust and mantle materials. Moreover, we propose that the VMS mineral system and hydrothermal vein system of the Kalatag district were related to the south-dipping subduction of the Kalamaili oceanic plate during the Late Ordovician-Silurian.
Original languageEnglish
Pages (from-to)72-81
JournalOre Geology Reviews
Volume77
DOIs
Publication statusPublished - Sep 2016

Fingerprint

Geochronology
Mineral resources
mineral deposit
chalcopyrite
Deposits
Quartz
Ores
Minerals
quartz
pyrite
Volcanic rocks
mineral
mineralization
Silurian
Ordovician
volcanic rock
Chlorite minerals
carbonate
tetrahedrite
metallogenesis

Cite this

Deng, X.H. ; Wang, J.B. ; Pirajno, Franco ; Wang, Y.W. ; Li, Y.C. ; Li, C. ; Zhou, L.M. ; Chen, Y.J. / Re-Os dating of chalcopyrite from selected mineral deposits in the Kalatag district in the eastern Tianshan Orogen, China. In: Ore Geology Reviews. 2016 ; Vol. 77. pp. 72-81.
@article{09dfcfaa940e4493a5a9975a55b7cdfd,
title = "Re-Os dating of chalcopyrite from selected mineral deposits in the Kalatag district in the eastern Tianshan Orogen, China",
abstract = "{\circledC} 2016 Elsevier B.V. The Kalatag Cu-Zn-Au district contains a number of economically important Cu deposits in eastern Tianshan in Xinjiang, NW China. Due to the lack of precise mineralization ages, the metallogenesis of this area has long been a matter of debate. In this study, chalcopyrite Re-Os isotope methods are used to date the South Meiling Cu-Zn and Hongshi Cu deposits in the eastern part of Kalatag area.The South Meiling Cu-Zn deposit is hosted in volcanic-sedimentary rocks of the Late Ordovician to Early Silurian Daliugou Formation. The deposit consists of two parts: a concordant massive sulfide ores and discordant vein-type ores located in the footwall strata. The principal ore minerals are pyrite, chalcopyrite, sphalerite, minor tetrahedrite, galena and pyrrhotite. Gangue minerals include quartz, sericite and barite, and minor chlorite, plagioclase and carbonate minerals. The Hongshi Cu deposit represents a hydrothermal vein system hosted in the mafic volcanic rocks of Daliugou Formation. The orebodies are associated with quartz veins and controlled by subsidiary faults of the Kalatag fault. The ore-forming process can be divided into the early, middle and late stages and is characterized by quartz-pyrite, quartz-chalcopyrite-pyrite and quartz-carbonate-gypsum veins, respectively.Re-Os analyses of chalcopyrite from the South Meiling Cu-Zn deposit yield an isochron age of 434.2 ± 3.9 Ma and initial 187Os/188Os ratio of 0.647 ± 0.098 (MSWD = 0.59). Re-Os analyses of chalcopyrite from the Hongshi Cu deposit yield an isochron age of 431.8 ± 2.7 Ma and initial 187Os/188Os ratio of -0.165 ± 0.075 (MSWD = 0.77). Since chalcopyrite is the primary copper mineral, we interpret these isochron ages as the timing of Cu mineralization, based on field geology and petrographic evidence. These results suggest that the Re-Os ages presented here provide, for the first time, a direct constraint on an early Paleozoic Cu mineralization event of the eastern Tianshan Orogen. The high initial 187Os/188Os ratios (0.647 ± 0.098) ratio of ~434 Ma chalcopyrite from the South Meiling deposit suggest that the metal was sourced from a two end-member mixing of crust and mantle materials. Moreover, we propose that the VMS mineral system and hydrothermal vein system of the Kalatag district were related to the south-dipping subduction of the Kalamaili oceanic plate during the Late Ordovician-Silurian.",
author = "X.H. Deng and J.B. Wang and Franco Pirajno and Y.W. Wang and Y.C. Li and C. Li and L.M. Zhou and Y.J. Chen",
year = "2016",
month = "9",
doi = "10.1016/j.oregeorev.2016.01.014",
language = "English",
volume = "77",
pages = "72--81",
journal = "Ore Geology Reviews",
issn = "0169-1368",
publisher = "Pergamon",

}

Re-Os dating of chalcopyrite from selected mineral deposits in the Kalatag district in the eastern Tianshan Orogen, China. / Deng, X.H.; Wang, J.B.; Pirajno, Franco; Wang, Y.W.; Li, Y.C.; Li, C.; Zhou, L.M.; Chen, Y.J.

In: Ore Geology Reviews, Vol. 77, 09.2016, p. 72-81.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Re-Os dating of chalcopyrite from selected mineral deposits in the Kalatag district in the eastern Tianshan Orogen, China

AU - Deng, X.H.

AU - Wang, J.B.

AU - Pirajno, Franco

AU - Wang, Y.W.

AU - Li, Y.C.

AU - Li, C.

AU - Zhou, L.M.

AU - Chen, Y.J.

PY - 2016/9

Y1 - 2016/9

N2 - © 2016 Elsevier B.V. The Kalatag Cu-Zn-Au district contains a number of economically important Cu deposits in eastern Tianshan in Xinjiang, NW China. Due to the lack of precise mineralization ages, the metallogenesis of this area has long been a matter of debate. In this study, chalcopyrite Re-Os isotope methods are used to date the South Meiling Cu-Zn and Hongshi Cu deposits in the eastern part of Kalatag area.The South Meiling Cu-Zn deposit is hosted in volcanic-sedimentary rocks of the Late Ordovician to Early Silurian Daliugou Formation. The deposit consists of two parts: a concordant massive sulfide ores and discordant vein-type ores located in the footwall strata. The principal ore minerals are pyrite, chalcopyrite, sphalerite, minor tetrahedrite, galena and pyrrhotite. Gangue minerals include quartz, sericite and barite, and minor chlorite, plagioclase and carbonate minerals. The Hongshi Cu deposit represents a hydrothermal vein system hosted in the mafic volcanic rocks of Daliugou Formation. The orebodies are associated with quartz veins and controlled by subsidiary faults of the Kalatag fault. The ore-forming process can be divided into the early, middle and late stages and is characterized by quartz-pyrite, quartz-chalcopyrite-pyrite and quartz-carbonate-gypsum veins, respectively.Re-Os analyses of chalcopyrite from the South Meiling Cu-Zn deposit yield an isochron age of 434.2 ± 3.9 Ma and initial 187Os/188Os ratio of 0.647 ± 0.098 (MSWD = 0.59). Re-Os analyses of chalcopyrite from the Hongshi Cu deposit yield an isochron age of 431.8 ± 2.7 Ma and initial 187Os/188Os ratio of -0.165 ± 0.075 (MSWD = 0.77). Since chalcopyrite is the primary copper mineral, we interpret these isochron ages as the timing of Cu mineralization, based on field geology and petrographic evidence. These results suggest that the Re-Os ages presented here provide, for the first time, a direct constraint on an early Paleozoic Cu mineralization event of the eastern Tianshan Orogen. The high initial 187Os/188Os ratios (0.647 ± 0.098) ratio of ~434 Ma chalcopyrite from the South Meiling deposit suggest that the metal was sourced from a two end-member mixing of crust and mantle materials. Moreover, we propose that the VMS mineral system and hydrothermal vein system of the Kalatag district were related to the south-dipping subduction of the Kalamaili oceanic plate during the Late Ordovician-Silurian.

AB - © 2016 Elsevier B.V. The Kalatag Cu-Zn-Au district contains a number of economically important Cu deposits in eastern Tianshan in Xinjiang, NW China. Due to the lack of precise mineralization ages, the metallogenesis of this area has long been a matter of debate. In this study, chalcopyrite Re-Os isotope methods are used to date the South Meiling Cu-Zn and Hongshi Cu deposits in the eastern part of Kalatag area.The South Meiling Cu-Zn deposit is hosted in volcanic-sedimentary rocks of the Late Ordovician to Early Silurian Daliugou Formation. The deposit consists of two parts: a concordant massive sulfide ores and discordant vein-type ores located in the footwall strata. The principal ore minerals are pyrite, chalcopyrite, sphalerite, minor tetrahedrite, galena and pyrrhotite. Gangue minerals include quartz, sericite and barite, and minor chlorite, plagioclase and carbonate minerals. The Hongshi Cu deposit represents a hydrothermal vein system hosted in the mafic volcanic rocks of Daliugou Formation. The orebodies are associated with quartz veins and controlled by subsidiary faults of the Kalatag fault. The ore-forming process can be divided into the early, middle and late stages and is characterized by quartz-pyrite, quartz-chalcopyrite-pyrite and quartz-carbonate-gypsum veins, respectively.Re-Os analyses of chalcopyrite from the South Meiling Cu-Zn deposit yield an isochron age of 434.2 ± 3.9 Ma and initial 187Os/188Os ratio of 0.647 ± 0.098 (MSWD = 0.59). Re-Os analyses of chalcopyrite from the Hongshi Cu deposit yield an isochron age of 431.8 ± 2.7 Ma and initial 187Os/188Os ratio of -0.165 ± 0.075 (MSWD = 0.77). Since chalcopyrite is the primary copper mineral, we interpret these isochron ages as the timing of Cu mineralization, based on field geology and petrographic evidence. These results suggest that the Re-Os ages presented here provide, for the first time, a direct constraint on an early Paleozoic Cu mineralization event of the eastern Tianshan Orogen. The high initial 187Os/188Os ratios (0.647 ± 0.098) ratio of ~434 Ma chalcopyrite from the South Meiling deposit suggest that the metal was sourced from a two end-member mixing of crust and mantle materials. Moreover, we propose that the VMS mineral system and hydrothermal vein system of the Kalatag district were related to the south-dipping subduction of the Kalamaili oceanic plate during the Late Ordovician-Silurian.

U2 - 10.1016/j.oregeorev.2016.01.014

DO - 10.1016/j.oregeorev.2016.01.014

M3 - Article

VL - 77

SP - 72

EP - 81

JO - Ore Geology Reviews

JF - Ore Geology Reviews

SN - 0169-1368

ER -