Geodynamics and plume tectonics of the Azore-Gibraltar fault zone (North Atlantic)

• Published in: Oceanology (Washington. 1965) Vol. 51; no. 5; pp. 876 - 890
• Main Authors: Verzhbitsky, E. V., Kononov, M. V., Byakov, A. F., Grinberg, O. V.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01.10.2011; Springer Nature B.V
• Subjects: Computer based modeling; Earth and Environmental Science; Earth Sciences; Geophysics; Marine; Marine Geology; Ocean bottom; Oceanography; Plate tectonics; Atlantic Ocean; AN, North Atlantic; PSW, Africa; African Plate; A, Mid-Atlantic Ridge; ANE, Atlantic, Azores; ASE, Africa; MED, Western Mediterranean; Azores Fragment; Tagus Basin; Eastern Flank; Reykjanes Ridge; Thermal Flow
• ISSN: 0001-4370; 1531-8508
• DOI: 10.1134/S0001437011050195

Maps of the principal structures and geological-geophysical knowledge for the Azores-Gibraltar and Icelandic regions have been made. The geodynamic conditions of the Azores archipelago formation have been analyzed. It has been noted that the uplifting of the Azores plume (as well as the Icelandic one) might have been triggered by near-surface tectonic processes. The computer modeling has been performed with respect to the coefficients of the geodynamic sinking rates for the Azores fragment of the Mid-Atlantic Ridge. Based on the modeling results, this rate was ∼1.5 times higher than the average sinking rate for the mid-ocean ridges of the World Ocean in general. The high sinking rate of the Azores fragment is caused by the influence of the plume material on the sinking process. Based on the complex analysis of the seismicity, thermal flow, and seismic tomography data distribution, as well as the implemented numerical calculations, the European (northern) part of the diffuse boundary between the Eurasian and African plates has been identified for the first time. Along with the African (southern) boundary, it outlines the identified by the authors West Mediterranean plate.