Academic Journal
Decoupled crust-mantle accommodation of Africa-Eurasia convergence in the NW Moroccan margin
| العنوان: | Decoupled crust-mantle accommodation of Africa-Eurasia convergence in the NW Moroccan margin |
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| المؤلفون: | Jimenez-Munt, Ivone, Fernández Ortiga, Manel, Vergés, Jaume, García-Castellanos, Daniel, Fullea, J., Pérez-Gussinyé, M., Afonso, Juan Carlos |
| بيانات النشر: | American Geophysical Union |
| سنة النشر: | 2011 |
| المجموعة: | Digital.CSIC (Consejo Superior de Investigaciones Científicas / Spanish National Research Council) |
| الوصف: | The extent of the area accommodating convergence between the African and Iberian plates, how this convergence is partitioned between crust and mantle, and the role of the plate boundary in accommodating deformation are not well-understood subjects. We calculate the structure of the lithosphere derived from its density distribution along a profile running from the Tagus Abyssal Plain to the Sahara Platform and crossing the Gorringe Bank, the NW Moroccan margin, and the Atlas Mountains. The model is based on the integration of gravity, geoid, elevation, and heat flow data and on the crustal structure across the NW Moroccan margin derived from reflection and wide-angle seismic data. The resulting mantle density anomalies suggest important variations of the lithosphere-asthenosphere boundary (LAB) topography, indicating prominent lithospheric mantle thickening beneath the margin (LAB > 200 km depth) followed by thinning beneath the Atlas Mountains (LAB similar to 90 km depth). At crustal levels the Iberia-Africa convergence is sparsely accommodated in a similar to 950 km wide area and localized in the Atlas and Gorringe regions, with an inferred shortening of similar to 50 km. In contrast, mantle thickening accommodates a 400 km wide region, thus advocating for a decoupled crustal-mantle mechanical response. A combination of mantle underthrusting due to oblique convergence, together with a viscous dripping fed by lateral mantle dragging, can explain the imaged lithospheric structure. The model is consistent with crustal shortening estimates and with the accommodation of part of the Iberia-Africa convergence farther NW of the Gorringe Bank and/or off the strike of the profile. ; This research was funded partly by Projects TopoMed (CGL2008‐03474‐E/BTE), ESF‐Eurocores 07‐ TOPOEUROPE‐FP006, TopoAtlas (CGL2006‐05493/BTE), SISAT (CGL2008‐01124‐E/BTE), ATIZA (CGL2009‐09662‐BTE), and Consolider‐Ingenio 2010 Topo‐Iberia (CSD2006‐00041). ; Peer Reviewed |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | Journal of Geophysical Research 116: B08403 (2011); http://hdl.handle.net/10261/74780 |
| DOI: | 10.1029/2010JB008105 |
| الاتاحة: | http://hdl.handle.net/10261/74780 https://doi.org/10.1029/2010JB008105 |
| Rights: | open |
| رقم الانضمام: | edsbas.51F682BB |
| قاعدة البيانات: | BASE |
| DOI: | 10.1029/2010JB008105 |
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