Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China
The West Qinling Orogen (WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits (>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic (T3–J1) and one only recently identified in the Late J...
| Main Authors: | , , , , |
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| Format: | Journal Article |
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Elsevier
2018
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| Online Access: | http://hdl.handle.net/20.500.11937/70993 |
| _version_ | 1848762360534138880 |
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| author | Wu, Y. Li, J. Evans, Katy Fougerouse, Denis Rempel, Kirsten |
| author_facet | Wu, Y. Li, J. Evans, Katy Fougerouse, Denis Rempel, Kirsten |
| author_sort | Wu, Y. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The West Qinling Orogen (WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits (>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic (T3–J1) and one only recently identified in the Late Jurassic to Early Cretaceous (J3–K1). Few studies have focused on the origin and geotectonic setting of the J3–K1 gold deposits. Textural relationships, LA-ICP-MS trace element and sulfur isotope compositions of pyrites in hydrothermally altered T3 dykes within the J3–K1 Daqiao deposit were used to constrain relative timing relationships between mineralization and pyrite growth in the dykes, and to characterize the source of ore fluid. These results are integrated with an overview of the regional geodynamic setting, to advance understanding of the tectonic driver for J3–K1 hydrothermal gold systems. Pyrite in breccia- and dyke-hosted gold ores at Daqiao have similar chemical and isotopic compositions and are considered to be representative of J3–K1 gold deposits in WQO. Co/Ni and sulfur isotope ratios suggest that ore fluids were derived from underlying Paleozoic Ni- and Se-rich carbonaceous sedimentary rocks. The geochemical data do not support the involvement of magmatic fluids. However, in the EQO (East Qinling Orogen), J3–K1 deposits are genetically related to magmatism. Gold mineralization in WQO is contemporaneous with magmatic deposits in the EQO and both are mainly controlled by NE- and EW-trending structures produced by changes in plate motion of the Paleo-Pacific plate as it was subducted beneath the Eurasian continent. We therefore infer that the J3–K1 structural regime facilitated the ascent of magma in the EQO and metamorphic fluids in the WQO with consequent differences in the character of contemporaneous ore deposits. If this is correct, then the far-field effects of subduction along the eastern margin of NE Asia extended 1000's of km into the continental interior. |
| first_indexed | 2025-11-14T10:46:20Z |
| format | Journal Article |
| id | curtin-20.500.11937-70993 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:46:20Z |
| publishDate | 2018 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-709932019-02-20T01:46:05Z Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China Wu, Y. Li, J. Evans, Katy Fougerouse, Denis Rempel, Kirsten The West Qinling Orogen (WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits (>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic (T3–J1) and one only recently identified in the Late Jurassic to Early Cretaceous (J3–K1). Few studies have focused on the origin and geotectonic setting of the J3–K1 gold deposits. Textural relationships, LA-ICP-MS trace element and sulfur isotope compositions of pyrites in hydrothermally altered T3 dykes within the J3–K1 Daqiao deposit were used to constrain relative timing relationships between mineralization and pyrite growth in the dykes, and to characterize the source of ore fluid. These results are integrated with an overview of the regional geodynamic setting, to advance understanding of the tectonic driver for J3–K1 hydrothermal gold systems. Pyrite in breccia- and dyke-hosted gold ores at Daqiao have similar chemical and isotopic compositions and are considered to be representative of J3–K1 gold deposits in WQO. Co/Ni and sulfur isotope ratios suggest that ore fluids were derived from underlying Paleozoic Ni- and Se-rich carbonaceous sedimentary rocks. The geochemical data do not support the involvement of magmatic fluids. However, in the EQO (East Qinling Orogen), J3–K1 deposits are genetically related to magmatism. Gold mineralization in WQO is contemporaneous with magmatic deposits in the EQO and both are mainly controlled by NE- and EW-trending structures produced by changes in plate motion of the Paleo-Pacific plate as it was subducted beneath the Eurasian continent. We therefore infer that the J3–K1 structural regime facilitated the ascent of magma in the EQO and metamorphic fluids in the WQO with consequent differences in the character of contemporaneous ore deposits. If this is correct, then the far-field effects of subduction along the eastern margin of NE Asia extended 1000's of km into the continental interior. 2018 Journal Article http://hdl.handle.net/20.500.11937/70993 10.1016/j.gsf.2018.09.005 http://creativecommons.org/licenses/by-nc-nd/4.0/ Elsevier fulltext |
| spellingShingle | Wu, Y. Li, J. Evans, Katy Fougerouse, Denis Rempel, Kirsten Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title | Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title_full | Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title_fullStr | Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title_full_unstemmed | Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title_short | Source and possible tectonic driver for Jurassic–Cretaceous gold deposits in the West Qinling Orogen, China |
| title_sort | source and possible tectonic driver for jurassic–cretaceous gold deposits in the west qinling orogen, china |
| url | http://hdl.handle.net/20.500.11937/70993 |