On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis
Lithospheric strength variations both influence and are influenced by many tectonic processes, including orogenesis and rifting cycles. The long, complex, and highly anisotropic histories of the continental lithosphere might lead to a natural expectation of widespread mechanical anisotropy. Anisotro...
| Main Authors: | , , , , |
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| Format: | Journal Article |
| Published: |
Elsevier BV
2015
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| Online Access: | http://hdl.handle.net/20.500.11937/34805 |
| _version_ | 1848754323065929728 |
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| author | Kalnins, L. Simons, F. Kirby, Jon Wang, D. Olhede, S. |
| author_facet | Kalnins, L. Simons, F. Kirby, Jon Wang, D. Olhede, S. |
| author_sort | Kalnins, L. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Lithospheric strength variations both influence and are influenced by many tectonic processes, including orogenesis and rifting cycles. The long, complex, and highly anisotropic histories of the continental lithosphere might lead to a natural expectation of widespread mechanical anisotropy. Anisotropy in the coherence between topography and gravity anomalies is indeed often observed, but whether it corresponds to an elastic thickness that is anisotropic remains in question. If coherence is used to estimate flexural strength of the lithosphere, the null-hypothesis of elastic isotropy can only be rejected when there is significant anisotropy in both the coherence and the elastic strengths derived from it, and if interference from anisotropy in the data themselves can be plausibly excluded. We consider coherence estimates made using multitaper and wavelet methods, from which estimates of effective elastic thickness are derived. We develop a series of statistical and geophysical tests for anisotropy, and specifically evaluate the potential for spurious results with synthetically generated data. Our primary case study, the North American continent, does not exhibit meaningful anisotropy in its mechanical strength. Similarly, a global reanalysis of continental gravity and topography using multitaper methods produces only scant evidence for lithospheric flexural anisotropy. |
| first_indexed | 2025-11-14T08:38:35Z |
| format | Journal Article |
| id | curtin-20.500.11937-34805 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:38:35Z |
| publishDate | 2015 |
| publisher | Elsevier BV |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-348052017-09-13T15:35:58Z On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis Kalnins, L. Simons, F. Kirby, Jon Wang, D. Olhede, S. lithospheric flexure elastic thickness lithospheric anisotropy hypothesis testing tectonic inheritance Lithospheric strength variations both influence and are influenced by many tectonic processes, including orogenesis and rifting cycles. The long, complex, and highly anisotropic histories of the continental lithosphere might lead to a natural expectation of widespread mechanical anisotropy. Anisotropy in the coherence between topography and gravity anomalies is indeed often observed, but whether it corresponds to an elastic thickness that is anisotropic remains in question. If coherence is used to estimate flexural strength of the lithosphere, the null-hypothesis of elastic isotropy can only be rejected when there is significant anisotropy in both the coherence and the elastic strengths derived from it, and if interference from anisotropy in the data themselves can be plausibly excluded. We consider coherence estimates made using multitaper and wavelet methods, from which estimates of effective elastic thickness are derived. We develop a series of statistical and geophysical tests for anisotropy, and specifically evaluate the potential for spurious results with synthetically generated data. Our primary case study, the North American continent, does not exhibit meaningful anisotropy in its mechanical strength. Similarly, a global reanalysis of continental gravity and topography using multitaper methods produces only scant evidence for lithospheric flexural anisotropy. 2015 Journal Article http://hdl.handle.net/20.500.11937/34805 10.1016/j.epsl.2015.02.041 Elsevier BV fulltext |
| spellingShingle | lithospheric flexure elastic thickness lithospheric anisotropy hypothesis testing tectonic inheritance Kalnins, L. Simons, F. Kirby, Jon Wang, D. Olhede, S. On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title | On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title_full | On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title_fullStr | On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title_full_unstemmed | On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title_short | On the robustness of estimates of mechanical anisotropy in the continental lithosphere: A North American case study and global reanalysis |
| title_sort | on the robustness of estimates of mechanical anisotropy in the continental lithosphere: a north american case study and global reanalysis |
| topic | lithospheric flexure elastic thickness lithospheric anisotropy hypothesis testing tectonic inheritance |
| url | http://hdl.handle.net/20.500.11937/34805 |