| Title | Thrust–wrench interference between major active faults in the Gulf of Cadiz (Africa–Eurasia plate boundary, offshore SW Iberia): Tectonic implications from coupled analog and numerical modeling |
| Publication Type | Journal Article |
| Year of Publication | 2012 |
| Authors | Rosas F.M., Duarte J.C., Neves M.C., Terrinha P., Silva S., Matias L., Gràcia E., Bartolome R. |
| Journal | Tectonophysics |
| Volume | 548-549 |
| Pagination | 1–21 |
| Date Published | jun |
| ISSN | 00401951 |
| Keywords | Analog and numerical modeling, Fault interference, Gulf of Cadiz, Lithospheric mantle seismicity, Multi-rupture seismic hazards, Thrust-wrench tectonics |
| Abstract | Analog and numerical modeling experiments were carried out to investigate the tectonic interference between intersecting major active strike-slip and thrust faults in the Gulf of Cadiz (Africa-Eurasia plate boundary, offshore SW Iberia). The obtained results show that newly mapped tectonic features located in the fault intersection area (corner zone) consist mostly in oblique (dextral-reverse) faults that accommodate significant strain partitioning. Modeling of this corner-zone faults show that they have endured some degree of rotation, displaying successive evolving geometries and kinematics. Numerical modeling results further show that an interbedded shallow soft layer, accounting for a regional (Late Miocene) gravitational "Chaotic" unit, could explain the mild bathymetric expression of the fault pattern in the corner-zone. Moreover, a recognized depth discrepancy, between the (upper crust) interference fault-pattern and the (lithospheric mantle) seismicity, is interpreted as a manifestation of similar thrust-wrench tectonic interference at different lithospheric depths. Accordingly, an intermediate lower crust-upper mantle aseismic (i.e. softened) depth-domain could be explained by pervasive alteration/serpentinization, prompted by fluid percolation through fault-related fractures associated with the newly revealed corner zone fault-network. Overall obtained results reinforce the relevance of a thrust-wrench multi-rupture seismic scenario as the main cause for the moderate seismicity (Mw < 6.0) in the study area. © 2012 Elsevier B.V. |
| URL | http://www.scopus.com/inward/record.url?eid=2-s2.0-84862115104&partnerID=tZOtx3y1 |
| DOI | 10.1016/j.tecto.2012.04.013 |
