Palaeomagnetic study of a subaerial volcanic ridge (Sao Jorge Island, Azores) for the past 1.3 Myr: evidence for the Cobb Mountain Subchron, volcano flank instability and tectonomagmatic implications

We present a palaeomagnetic study on 38 lava flows and 20 dykes encompassing the past 1.3 Myr on S. Jorge Island (Azores ArchipelagoNorth Atlantic Ocean). The sections sampled in the southeastern and central/western parts of the island record reversed and normal polarities, respectively. They indicate a mean palaeomagnetic pole (81.3 degrees N, 160.7 degrees E, K= 33 and A95= 3.4 degrees) with a latitude shallower than that expected from Geocentric Axial Dipole assumption, suggesting an effect of non-dipolar components of the Earth magnetic field. Virtual Geomagnetic Poles of eight flows and two dykes closely follow the contemporaneous records of the Cobb Mountain Subchron (ODP/DSDP programs) and constrain the age transition from reversed to normal polarity at ca. 1.207 +/- 0.017 Ma. Volcano flank instabilities, probably related to dyke emplacement along an NNWSSE direction, led to southwestward tilting of the lava pile towards the sea. Two spatially and temporally distinct dyke systems have been recognized on the island. The eastern is dominated by NNWSSE trending dykes emplaced before the end of the Matuyama Chron, whereas in the central/western parts the eruptive fissures oriented WNWESE controlled the westward growth of the S. Jorge Island during the Brunhes Chron. Both directions are consistent with the present-day regional stress conditions deduced from plate kinematics and tectonomorphology and suggest the emplacement of dykes along pre-existing fractures. The distinct timing and location of each dyke system likely results from a slight shift of the magmatic source.

Mantle source heterogeneity, magma generation and magmatic evolution at Terceira Island (Azoresarchipelago): Constraints from elemental and isotopic (Sr, Nd, Hf, and Pb) data

This work addresses the present-day (<100 ka) mantle heterogeneity in the Azores region through the study of two active volcanic systems from Terceira Island. Our study shows that mantle heterogeneities are detectable even when "coeval" volcanic systems (Santa Barbara and Fissural) erupted less than 10 km away. These volcanic systems, respectively, reflect the influence of the Terceira and D. Joao de Castro Bank end-members defined by Beier et at (2008) for the Terceira Rift Santa Barbara magmas are interpreted to be the result of mixing between a HIMU-type component, carried to the upper mantle by the Azores plume, and the regional depleted MORB magmas/source. Fissural lavas are characterized by higher Ba/Nb and Nb/U ratios and less radiogenic Pb-206/Pb-204, Nd-143/Nd-144 and Hf-176/Hf-177, requiring the small contribution of delaminated sub-continental lithospheric mantle residing in the upper mantle. Published noble gas data on lavas from both volcanic systems also indicate the presence of a relatively undegassed component, which is interpreted as inherited from a lower mantle reservoir sampled by the ascending Azores plume. As inferred from trace and major elements, melting began in the garnet stability field, while magma extraction occurred within the spinel zone. The intra-volcanic system's chemical heterogeneity is mainly explained by variable proportions of the above-mentioned local end-members and by crystal fractionation processes. (C) 2011 Elsevier By. All rights reserved.

Auxílios de Estado sob a forma fiscal: O caso Açores - Proc. C-88/03

Mestrado em Fiscalidade

Perceção do consumidor sobre marcas de lacticínios dos Açores

Dissertação de Mestrado, Ciências Económicas e Empresariais, 6 de Dezembro de 2012, Universidade dos Açores.

Educação para o Desenvolvimento Sustentável (EDS) no âmbito do Currículo Regional da Educação Básica da Região Autónoma dos Açores (CREB)

Mestrado, Educação Pré-Escolar e Ensino do 1.º Ciclo do Ensino Básico, 26 de Junho de 2013, Universidade dos Açores (Relatório de Estágio).

Recursos hidrominerais dos Açores: hidrogeologia e avaliação do potencial sócioeconómico

Tese de Doutoramento, Geologia (Hidrogeologia), 17 de Dezembro de 2013, Universidade dos Açores.

Perspectives and progress of ecology and conservation science in the Azores: the possible contribution of Artificial Intelligence

EPIA 2013 - XVI Portuguese Conference on Artificial Intelligence Angra do Heroísmo, Azores, Portugal, 9 – 12 September.

Diversidade de briófitos e alterações climáticas nos Açores: olhar para o futuro para delinear o presente

Jornadas "Ciência nos Açores – que futuro? Tema Ciências Naturais e Ambiente", Ponta Delgada, 7-8 de Junho de 2013.

The surplus value of Azorean macroalgae as health-promoting food. Protein, fiber, carbohydrates, lipids and vitamins determination

AICMA 2012 (BIT's 1st Annual International Congress of Marine Algae), World Expo Center, Dalian, China, 20-23 de Setembro.

Investigação em comunidades dominadas por macroalgas: situação actual, aplicações e desenvolvimentos futuros

Conhecer o Mar dos Açores. Fórum Científico de Apoio à Decisão, Horta, 19 de Janeiro de 2011.

Microalgae production for commercial purposes in the Azores

IBBA Strategic Planning - Workshop III, Plant Biotechnology Ponta Delgada, 25 Janeiro, 2011.

Azores marine algal flora: how endangered is it?

Unesco chair for "Conservation of plant biodiversity in Macaronesia and the West of Africa", Gran Canaria, 27-28 November 2013.

Modelling the distribution of cetaceans using opportunistic presence-only data in S. Miguel Island (Azores)

25th Annual Conference of the European Cetacean Society, Cadiz, Spain 21-23 March 2011.

AzoresPhotoID: first results from an open-access photoidentification catalogue

25th Conference of the European Cetacean Society. Long-terms datasets on marine mammals: learning from the past to manage the future, Cadiz, Spain, 21-23 March 2011.

The presence of the sperm whale (Physeter macrocephalus) around the Azores: a study of re-sightings from 2003-2012

27th Annual Conference of the European Cetacean Society. Setúbal, Portugal, 8-10 April 2013.