A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China
High seismic velocity layers within the lower crust (i.e. ~40. km) of the Yangtze Block are interpreted as mafic underplated rocks derived from the Late Permian Emeishan mantle plume. However, the region experienced a previous magmatic event during the Neoproterozoic (~800. Ma) that produced the Kan...
| Main Authors: | , , , |
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| Format: | Journal Article |
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Pergamon Press
2015
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| Online Access: | http://hdl.handle.net/20.500.11937/45615 |
| _version_ | 1848757335264067584 |
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| author | Shellnutt, J. Usuki, T. Kennedy, Allen Chiu, H. |
| author_facet | Shellnutt, J. Usuki, T. Kennedy, Allen Chiu, H. |
| author_sort | Shellnutt, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | High seismic velocity layers within the lower crust (i.e. ~40. km) of the Yangtze Block are interpreted as mafic underplated rocks derived from the Late Permian Emeishan mantle plume. However, the region experienced a previous magmatic event during the Neoproterozoic (~800. Ma) that produced the Kangdian basalts and associated mafic intrusions and therefore the lower crust seismic velocity layers may represent a mixture of two different magmatic episodes. The identification of inherited Neoproterozoic (i.e. ~750 to ~850. Ma) zircons within Emeishan magmatic rocks indicates either assimilation of older material during emplacement or that the rocks could be derived from a mafic Neoproterozoic precursor. Equilibrium partial melt modeling of Neoproterozoic Kangdian basalts can produce compositions similar to Emeishan basalt at a pressure of 1.2. GPa (i.e. ˜40. km depth). It is suggested that the injection of high temperature picritic magmas into the lower crust of the Yangtze Block could be sufficient to induce high degrees of melting of the lower crust and produce magmas that are similar in composition to some Emeishan mafic rocks and/or produce melts that could contaminate 'pristine' Emieshan magmas. |
| first_indexed | 2025-11-14T09:26:27Z |
| format | Journal Article |
| id | curtin-20.500.11937-45615 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:26:27Z |
| publishDate | 2015 |
| publisher | Pergamon Press |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-456152017-09-13T15:41:03Z A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China Shellnutt, J. Usuki, T. Kennedy, Allen Chiu, H. High seismic velocity layers within the lower crust (i.e. ~40. km) of the Yangtze Block are interpreted as mafic underplated rocks derived from the Late Permian Emeishan mantle plume. However, the region experienced a previous magmatic event during the Neoproterozoic (~800. Ma) that produced the Kangdian basalts and associated mafic intrusions and therefore the lower crust seismic velocity layers may represent a mixture of two different magmatic episodes. The identification of inherited Neoproterozoic (i.e. ~750 to ~850. Ma) zircons within Emeishan magmatic rocks indicates either assimilation of older material during emplacement or that the rocks could be derived from a mafic Neoproterozoic precursor. Equilibrium partial melt modeling of Neoproterozoic Kangdian basalts can produce compositions similar to Emeishan basalt at a pressure of 1.2. GPa (i.e. ˜40. km depth). It is suggested that the injection of high temperature picritic magmas into the lower crust of the Yangtze Block could be sufficient to induce high degrees of melting of the lower crust and produce magmas that are similar in composition to some Emeishan mafic rocks and/or produce melts that could contaminate 'pristine' Emieshan magmas. 2015 Journal Article http://hdl.handle.net/20.500.11937/45615 10.1016/j.jseaes.2015.04.037 Pergamon Press fulltext |
| spellingShingle | Shellnutt, J. Usuki, T. Kennedy, Allen Chiu, H. A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title | A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title_full | A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title_fullStr | A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title_full_unstemmed | A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title_short | A lower crust origin of some flood basalts of the Emeishan large igneous province, SW China |
| title_sort | lower crust origin of some flood basalts of the emeishan large igneous province, sw china |
| url | http://hdl.handle.net/20.500.11937/45615 |