Compressional tectonic inversion of the Algero-Balearic basin: Latemost Miocene to present oblique convergence at the Palomares margin (Western Mediterranean)

Giaconia, F. ... et al.-- 28 pages, 14 figures, supporting information http://dx.doi.org/tect20290-sup-0001-supplementary.doc
Interpretation of new multichannel seismic reflection profiles indicates that the Palomares margin was formed by crustal-scale extension and coeval magmatic accretion during middle to late Miocene opening of the Algero-Balearic basin. The margin formed at the transition between thinned continental crust intruded by arc volcanism and back-arc oceanic crust. Deformation produced during the later positive inversion of the margin offshore and onshore is partitioned between ~N50°E striking reverse faults and associated folds like the Sierra Cabrera and Abubacer anticlines and N10-20°E sinistral strike-slip faults like Palomares and Terreros faults. Parametric subbottom profiles and multibeam bathymetry offshore, structural analysis, available GPS geodetic displacement data, and earthquake focal mechanisms jointly indicate that tectonic inversion of the Palomares margin is currently active. The Palomares margin shows a structural pattern comparable to the north Maghrebian margins where Africa-Eurasia plate convergence is accommodated by NE-SW reverse faults, NNW-SSE sinistral faults, and WNW-ESE dextral ones. Contractive structures at this margin contribute to the general inversion of the Western Mediterranean since -7Ma, coeval to inversion at the Algerian margin. Shortening at the Alboran ridge and Al-Idrisi faults occurred later, since 5Ma, indicating a westward propagation of the compressional inversion of the Western Mediterranean. ©2015. American Geophysical Union. All Rights Reserved
The seismic data were obtained in the frame of the European Science Foundation TopoEurope Project funded by the Spanish Ministry of Science and Innovation as TOPOMED CGL2008-03474-E project. The authors were supported by research group RNM148 (Junta de Andalucía), research group 2014 SGR 940 (Generalitat de Catalunya), and research projects CGL2011-29920, CSD2006-00041 TOPOIBERIA CONSOLIDER-INGENIO2010, CTM2007-66179-C02-01/MAR, CGL2011-30005-C02-02 SHAKE, and the CTM2011-30400-C02-01 HADES Project from the Spanish Ministry of Science and Innovation. We also acknowledge funding from the MICINN through the “Ramon y Cajal” (R. Bartolome) and Juan de la Cierva (H. Perea) programs