Academic Journal
Crustal thickness beneath Atlas region from gravity, topographic, sediment and seismic data
| Title: | Crustal thickness beneath Atlas region from gravity, topographic, sediment and seismic data |
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| Authors: | Franck Eitel Kemgang Ghomsi, Robert Tenzer, Sévérin Nguiya, Animesh Mandal, Robert Nouayou |
| Source: | Geodesy and Geodynamics, Vol 11, Iss 1, Pp 18-30 (2020) |
| Publisher Information: | KeAi Communications Co., Ltd., 2020. |
| Publication Year: | 2020 |
| Collection: | LCC:Geodesy LCC:Geophysics. Cosmic physics |
| Subject Terms: | Geodesy, QB275-343, Geophysics. Cosmic physics, QC801-809 |
| More Details: | The Atlas region in northwest Africa is characterized by the Quaternary volcanism and elevated topography with past complex tectonic mitigation between the African and European plates. Geodynamics of this atypical region has left indubitably imprints in crustal architectonics, mainly regarding the crustal thickness as well as the crustal density structure. The knowledge of crustal thickness variations is of a significant interest, since it provides a crucial constraint to geodynamic and geophysical modelling of this region. In this study, we use gravity, topographic, bathymetric and sediment data together with results of seismic surveys to image the Moho topography beneath the Atlas region. The Bouguer gravity anomalies used for a gravimetric Moho recovery are obtained from the free-air gravity anomalies after subtracting the gravitational contributions of topography, bathymetry and sediments. The regional gravimetric Moho inversion constrained on seismic data is carried out by applying a regularized inversion technique based on Gauss-Newton's formulation of improved Bott's method, while adopting Earth's spherical approximation. The numerical result reveals relatively significant Moho depth variations in the Moroccan Atlas, with minima of approximately 24 km along continental margins of the Mediterranean Sea and maxima exceeding 51 km beneath the Rif Cordillera. The Moho depth beneath the West African Craton varies from 32 km in its southern margin to 45 km beneath the Middle Atlas. The Tell Atlas is characterized by the shallow Moho depth of approximately 22 km and further deepening to 42 km towards the northern edge of the Aures Mountains. Our findings indicate a limited tectonic shortening of the High Atlas with the crustal thickness mostly within 36–42 km. Topographic discrepancies between the Rif Cordillera and the Atlas Mountains suggest that the hypothesis of isostatic compensation cannot be fully established. Keywords: Atlas, Gravity, Inversion, Moho, Seismic data |
| Document Type: | article |
| File Description: | electronic resource |
| Language: | English |
| ISSN: | 1674-9847 |
| Relation: | http://www.sciencedirect.com/science/article/pii/S1674984719300710; https://doaj.org/toc/1674-9847 |
| DOI: | 10.1016/j.geog.2019.08.002 |
| Access URL: | https://doaj.org/article/86b44d2d8f00499d8b26e3be5eccb46f |
| Accession Number: | edsdoj.86b44d2d8f00499d8b26e3be5eccb46f |
| Database: | Directory of Open Access Journals |
| ISSN: | 16749847 |
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| DOI: | 10.1016/j.geog.2019.08.002 |
| Published in: | Geodesy and Geodynamics |
| Language: | English |