Características de los tensores de esfuerzos activos entre la Dorsal Centroatlántica y la Península Ibérica
The orientation of the principal stresses and the principal stress difference ratio has been determined along the southwestern boundary of the Euroasiatic plate with Northamerican and African plates by inversion method of focal mechanisms of earthquakes. The ridge push (30~ to 65Q N) ranges from E-W...
| Autores: | , , , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2000 |
| País: | España |
| Recursos: | Universidad Complutense de Madrid (UCM) |
| Repositório: | Docta Complutense |
| Idioma: | espanhol |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/57956 |
| Acesso em linha: | https://hdl.handle.net/20.500.14352/57956 |
| Access Level: | Acceso aberto |
| Palavra-chave: | 551.24(234.1) Active stress tensors Focal mecanisms of earthquakes Inverse method Euroasiatic Plate Iberian peninsula Geodinámica 2507 Geofísica |
| Resumo: | The orientation of the principal stresses and the principal stress difference ratio has been determined along the southwestern boundary of the Euroasiatic plate with Northamerican and African plates by inversion method of focal mechanisms of earthquakes. The ridge push (30~ to 65Q N) ranges from E-W to ESE-WSW, with R values that show a triaxial extensional stress. The state of stress changes to strike-slip regime in the transform fault zones, and the Shmax strike turns clockwise to NW in the dextral strike-slip faults and counterclockwise to the NE in the sinistral ones. Along the margin between the Euroasiatic-African plates, from the Azores triple junction to Algeria, Shmax keeps a constant NW-SE strike but the stress ratio values range from triaxial extensional stress state, to the West, to uniaxial compresive stress state, to the East, passing through a strike-slip regime in the middle zone. In this context and with a widely NWSE Shmax, strike-slip and extensional stresses prevail in most Iberian peninsula, whereas southwards it is dominated by uniaxial compresive stresses. |
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