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- Imaging the crustal structure of the Azores islandsPublication . Dias, Nuno; Veludo, IdalinaThe Azores archipelago (Portugal), in the Central Atlantic Ocean, is located in a tectonic triple junction, between the American, Eurasia and African plates, whose morphologic expression is the Azores Plateau. Geodetic measurements indicate spreading rates of 23 mm/year for the Mid-Atlantic Ridge (MAR) and 2.1 mm/year for the Azorean segment (Terceira Ridge). The Azores plateau is considered as the surface expression of the interaction between the Azores hotspot and the MAR, and presents significant tectonic and volcanic activity. The existence of an anomalously thick crust associated with excesso magmatism, related with the Hotspot, has long been established for the Plateau, however the detailed characterization on its crustal structure, and its variability within the plateau is not yet fully performed.
- The Portuguese national seismic network: products and servicesPublication . Carrilho, Fernando; Custodio, Susana; Bezzeghoud, Mourad; Oliveira, Carlos; Marreiros, Célia; Vales, Dina; Alves, Paulo; Pena, Areosa; Madureira, Guilherme; Escuer, Maria; Silveira, Graça; Corela, Carlos; Matias, Luis; Silva, Matilde; Veludo, Idalina; Dias, Nuno; Loureiro, Afonso; Borges, J. F.; Caldeira, Bento; Wachilala, Piedade; Fontiela, JoaoPortugal, located in the southwest region of the Eurasian plate, has been affected by several destructive earthquakes throughout its history, the most well-known being the 1755 Great Lisbon earthquake. The seismicity of the territory, both in the mainland and in the Azores and Madeira islands, has prompted the continuous development of seismic monitoring, from the first known macroseismic inquiry, following the 1755 Great Lisbon earthquake, to the current state-of-the-art seismic network. Once scattered in separate efforts, at present, most seismic stations in Portugal relay its data to a common data center, at Instituto Português do Mar e da Atmosfera, where data are automatically processed for the downstream generation of both manually revised and automatically generated products and services. In this article, we summarize the evolution of the permanent seismic network, its current status, the products and services that are publicly available, a recent effort of rapid deployment of a dense network following a mainshock, and state-of-the-art ocean-bottom seismometer developments.