Extended abstract/Short paper
Late Pleistocene deformation at Aljezur fault system, SW Portugal: Seismicity triggering within a low tectonic rate setting and relationship with sea-level rise
Participants in the publication
Figueiredo, P. M. (Author)
Rockwell , T. (Author)
IDL - Instituto Dom Luiz
The southwest of Portugal is located close to the Eurasia – Nubia plate boundary, characterized by an NW-SE to WNW-ESE oblique convergence at a rate of 4-6 mm/yr. Inland, this convergence is accommodated by several active structures with low tectonic rates (< 0.5 mm /yr). The São Teotónio – Aljezur - Sinceira Fault system (STASFS) is a 50 km long left-lateral strike-slip fault system, trending NNE-SSW, approximately parallel and close to the SW Portuguese coastline, with an estimated horizontal slip rate of 0.16 mm/yr. Holocene deformation was not recognized. Recent paleoseismological studies demonstrated that STASFS fault segments may have been subjected to an increase in Coulomb stress during periods of sea level rise. We suggest that late Pleistocene seismicity along STASFS might be related to periods of rapid sea-level rise, such as the one that occurred immediately after the Last Glacial Maximum, thereby releasing accumulated strain and allowing for ~15 ka of inactivity.
James P. McCalpin & Christoph Gruetzner
Date of Publication
Crestone Science Center, Crestone, CO 81131 USA, www.crestonescience.org
Crestone Science Center
ISBN - 9780997435528
Crestone, CO 81131 USA
GEO-HAZ Consulting, Inc.
Crestone Science Center, P.O. Box 837, Crestone, CO 81131 USA
Proceedings of the 7th International INQUA Workshop on Paleoseismology, Active Tectonics and Archaeoseismology (“PATA Days”) 30 May- 3 June 2016 Crestone, Colorado, USA