A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma
The Longmenshan Fault Zone (LFZ) is a tectonic boundary between the Tibetan Plateau and the Sichuan Basin of the South China Block. Knowledge of the nature and history of the LFZ is important for understanding the growth of continental plateaus and mechanisms for major earthquakes along their margin...
| Main Authors: | , , , |
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| Format: | Journal Article |
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American Geophysical Union
2019
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| Online Access: | https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1029/2018TC005272 http://hdl.handle.net/20.500.11937/74528 |
| _version_ | 1848763300150509568 |
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| author | Jiang, X. Li, Zheng-Xiang Li, C. Gong, W. |
| author_facet | Jiang, X. Li, Zheng-Xiang Li, C. Gong, W. |
| author_sort | Jiang, X. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The Longmenshan Fault Zone (LFZ) is a tectonic boundary between the Tibetan Plateau and the Sichuan Basin of the South China Block. Knowledge of the nature and history of the LFZ is important for understanding the growth of continental plateaus and mechanisms for major earthquakes along their margins, as exemplified by the magnitude 7.9 M Wenchuan earthquake of 12 May 2008. Flexural modeling of new and existing gravity survey data along three transects, combined with published seismic reflection profiles and earthquake focal mechanism data, indicates that the central-northern LFZ is a lithospheric-scale fault zone that has low elastic strength but with strong episodic dextral transpressional motions. In contrast, the southern LFZ is a crustal-scale thrust zone dominated by shallow-angle thrust motion of the Tibetan Plateau over a moderately stiff South China Block. In conjunction with the record of Cenozoic basin erosion in the western Sichuan Basin and a regional kinematic analysis, we suggest that the lithospheric-scale LFZ started 40 Myr ago and became an external boundary of a northeasterly directed extrusion-style plateau growth, predominantly through crustal thrusting and thickening. |
| first_indexed | 2025-11-14T11:01:16Z |
| format | Journal Article |
| id | curtin-20.500.11937-74528 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T11:01:16Z |
| publishDate | 2019 |
| publisher | American Geophysical Union |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-745282023-04-26T05:24:43Z A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma Jiang, X. Li, Zheng-Xiang Li, C. Gong, W. The Longmenshan Fault Zone (LFZ) is a tectonic boundary between the Tibetan Plateau and the Sichuan Basin of the South China Block. Knowledge of the nature and history of the LFZ is important for understanding the growth of continental plateaus and mechanisms for major earthquakes along their margins, as exemplified by the magnitude 7.9 M Wenchuan earthquake of 12 May 2008. Flexural modeling of new and existing gravity survey data along three transects, combined with published seismic reflection profiles and earthquake focal mechanism data, indicates that the central-northern LFZ is a lithospheric-scale fault zone that has low elastic strength but with strong episodic dextral transpressional motions. In contrast, the southern LFZ is a crustal-scale thrust zone dominated by shallow-angle thrust motion of the Tibetan Plateau over a moderately stiff South China Block. In conjunction with the record of Cenozoic basin erosion in the western Sichuan Basin and a regional kinematic analysis, we suggest that the lithospheric-scale LFZ started 40 Myr ago and became an external boundary of a northeasterly directed extrusion-style plateau growth, predominantly through crustal thrusting and thickening. 2019 Journal Article http://hdl.handle.net/20.500.11937/74528 10.1029/2018TC005272 https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1029/2018TC005272 http://purl.org/au-research/grants/arc/FL150100133 American Geophysical Union unknown |
| spellingShingle | Jiang, X. Li, Zheng-Xiang Li, C. Gong, W. A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title | A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title_full | A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title_fullStr | A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title_full_unstemmed | A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title_short | A Gravity Study of the Longmenshan Fault Zone: New Insights Into the Nature and Evolution of the Fault Zone and Extrusion-Style Growth of the Tibetan Plateau Since 40 Ma |
| title_sort | gravity study of the longmenshan fault zone: new insights into the nature and evolution of the fault zone and extrusion-style growth of the tibetan plateau since 40 ma |
| url | https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1029/2018TC005272 https://agupubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1029/2018TC005272 http://hdl.handle.net/20.500.11937/74528 |