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Com base na análise de cartas geológicas 1/50000 caracterizou-se a geometria da unidade alostratigráficaSLD13 (provável idade Zancleano final a Gelasiano; ca. 3,7 a 1,8 Ma) no onshore do Algarve; culmina oenchimento sedimentar. Concluiu-se que a descontinuidade sedimentar da base da SLD13 (aos 25 a 150 m asl)é uma vasta superfície de abrasão marinha, com suave declive subindo para terra, que na embocadura dosprincipais rios atuais passa a uma superfície erosiva com génese deltaica/estuarina a fluvial/aluvial (mais parainterior). O topo da SLD13 é uma superfície de agradação sedimentar, abandonada a quando do início da etapade encaixe da rede hidrográfica. Estimou-se a espessura original da SLD13 em ca.25-18 m. Após a deposiçãoda SLD13, existiu tectónica ativa responsável por desnivelamentos tectónicos em falhas com direções WSWENEa SSW-NNE e por basculamentos, conduzindo a soerguimento para oeste e subsidência a leste. Analysis of 1/50,000 geologic mapsallowed geometric characterization of the allostratigraphicunit SLD13(probable age- latestZanclean to Gelasian, ca. 3.7 to 1.8 Ma) in the Algarve onshore; it culminates the Cenozoicsedimentary infill. The sedimentary discontinuity at the SLD13 base (at 25 to 150 m asl) is a vast wave cutsurface, with low slope, that in the mouth of the coeval rivers is an erosive surface of deltaic/estuarine tofluvial/alluvial genesis. The SLD13 top is an aggradation surface, abandoned at the beginning of the fluvialincision stage. The thickness is estimated in ca. 25-18 m. After SLD13 genesis, displacements inWSW-ENEto SSW-NNE faults lead to subsidence at east but to progressive uplift towards west.

Só está disponível o resumo. A mina de urânio de Pinhal do Souto foi explorada subterraneamente entre 1978 e 1989, tendo produzido 93091 kg de U3O8. Na área ficaram duas escombreiras, parcialmente cobertas por vegetação natural. Nesta mina foi explorado um filão de quartzo contendo autunite e torbernite, que corta um granito de duas micas. A mina está a causar contaminação em U, As, Cd, Cr, Cu, Fe, Ni e Pb nas águas, em Cr, Mn, Pb, Cd, Co, Fe, Th, Zn e, por vezes, em U nos sedimentos de corrente e em Cu, Pb, Zn, As, Cd e Sb nos solos. Os valores da mediana de Fe, As, Cd, Pb, Sb, Th, U, W e Zn destes solos são superiores aos dos solos dos países europeus dos dados FOREGS. forma complexos com nas águas que têm pH neutro a alcalino. As concentrações de U na água são superiores aos limites para uso humano nas épocas húmida e seca, mas são maiores na época húmida por os minerais secundários de U se dissolverem e o U ser libertado na água. Os teores de metais e As são maiores na água da época seca devido à evaporação. Os solos têm vermiculite e, por isso, retêm maiores concentrações de metais do que os sedimentos de corrente que possuem caulinite. Devido aos valores de pH ligeiramente ácidos a neutros das águas, há a ocorrência de precipitados de óxido de Fe, sobretudo nas saídas de galerias subterrâneas, que são ricos em óxidos-hidróxidos e matéria orgânica e que retêm grandes quantidades de metais U, Th e As. Abstrac: The Pinhal do Souto uranium mine was exploited underground between 1978 and 1989 and produced 93091 kg U3O8. Two dumps partially covered by natural vegetation were left in the area. The mine exploited a quartz vein containing autunite and torbernite that cuts a two-mica granite. The mine caused contamination in U, As, Cd, Cr, Cu, Fe, Ni and Pb in waters, in Cr, Mn, Pb, Cd, Co, Fe, Th, Zn and locally in U in stream sediments and in Cu, Pb, Zn, As, Cd and Sb in soils. The median values of Fe, As, Cd, Pb, Sb, Th, U, W and Zn of these soils are higher than those of soils from European countries of the FOREGS data. is complexed with in waters under neutral to alkaline pH. The U concentrations in water are higher than the limits for human use in wet and dry seasons, but are higher in the wet season, because secondary uranium minerals are dissolved and uranium is released into the water. The metals and As contents are higher in water from the dry season, due to the evaporation. As the soils contain vermiculite they retain higher metals concentrations than stream sediments, which contain kaolinite. The Fe-oxide precipitate is richer in oxydroxydes and organic matter than stream sediments and consequently has higher concentrations of several metals, including U and Th and the metalloid As.

The development of seismogenic source models is one of the first steps in seismic hazard assessment. In seismic hazard terminology, seismic source zones (SSZ) are polygons (or volumes) that delineate areas with homogeneous characteristics of seismicity. The importance of using knowledge on geology, seismicity and tectonics in the definition of source zones has been recognized for a long time. However, the definition of SSZ tends to be subjective and controversial. In the FP7 Project SHARE (Seismic Hazard Harmonization in Europe), seismic hazard will be assessed with a logic tree approach that allows for three types of branches for seismicity models: a) smoothed seismicity, b) SSZ, c) SSZ and faults. In this context, a large-scale zonation model for use in the smoothed seismicity branch, and a new consensus SSZ model for Portugal and Azores have been developed. The new models are being achieved with the participation of regional experts and external experts, according the SSHAC (1997) level- 3 methodology.

The development of seismogenic source models is one of the first steps in seismic hazard assessment. In seismic hazard terminology, seismic source zones (SSZ) are polygons (or volumes) that delineate areas with homogeneous characteristics of seismicity. The importance of using knowledge on geology, seismicity and tectonics in the definition of source zones has been recognized for a long time [1]. However, the definition of SSZ tends to be subjective and controversial. Using SSZ based on broad geology, by spreading the seismicity clusters throughout the areal extent of a zone, provides a way to account for possible long-term non-stationary seismicity behavior [2,3]. This approach effectively increases seismicity rates in regions with no significant historical or instrumental seismicity, while decreasing seismicity rates in regions that display higher rates of seismicity. In contrast, the use of SSZ based on concentrations of seismicity or spatial smoothing results in stationary behavior [4]. In the FP7 Project SHARE (Seismic Hazard Harmonization in Europe), seismic hazard will be assessed with a logic tree approach that allows for three types of branches for seismicity models: a) smoothed seismicity, b) SSZ, c) SSZ and faults. In this context, a large-scale zonation model for use in the smoothed seismicity branch, and a new consensus SSZ model for Portugal and Azores have been developed. The new models were achieved with the participation of regional experts by combining and adapting existing models and incorporating new regional knowledge of the earthquake potential. The main criteria used for delineating the SSZ include distribution of seismicity, broad geological architecture, crustal characteristics (oceanic versus continental, tectonically active versus stable, etc.), historical catalogue completeness, and the characteristics of active or potentially-active faults. This model will be integrated into an Iberian model of SSZ to be used in the Project SHARE seismic hazard assessment.

IX Simpósio sobre a Margem Ibérica Atlântica (MIA 2018) - IX Simposio sobre el Margen Ibérico Atlántico - IX Symposium on the Iberian Atlantic Margin, 4-7 September de 2018, Coimbra.-- 2 pages, 1 figure, Several giant circular-elliptical depressions have been analyzed in the continental margins off North Iberian (NICM) and West Africa (WACM) by means of multibeam bathymetric data and seismic reflection profiles. Their long axes vary between 2 and 4.7 km, the width axis between 2 and 3.5 km and their reliefs between 40 and 370 m. Depressions are slightly elliptical with eccentricity index between 0.73 and 0.9. They are partially filled by sediments producing different V and U bathymetric crosssections. The Burato Ergap depression in the NICM and the Twin Pools depressions in the WACM occur overlying diapirs. Burato Ergap depression is originated as a collapse structure related to underlying diapiric mobility. Twin Pools depressions seem to represent seafloor reworking by the action of deep sea bottom currents interacting with and adjacent diapiric ridge on the seafloor, Study is integrated in the projects FAUCES CTM2015-65461-C2-2-R MINECO/FEDER, INPULSE CTM2016-75129-C3-1-R AEI/FEDER, EXPLOSEA CTM2016-75947-R and RNM-328 PAIDI group. Data proceed from ERGAP VEM2003-20093-CO3 and SUBVENT CGL2012-39524-C02 projects

IX Simpósio sobre a Margem Ibérica Atlântica (MIA 2018) - IX Simposio sobre el Margen Ibérico Atlántico - IX Symposium on the Iberian Atlantic Margin, 4-7 September de 2018, Coimbra.-- 2 pages, 1 figure, High-resolution multibeam bathymetry, seismic reflection data and underwater imagery were used to characterize the morphostructure as well as the ancient and contemporary habitat-forming species in three fields of clustered mounds that were recently discovered in the northern Alboran Sea. A total of 150 small mounds were detected between 140 to 300 m water depth. They display reliefs ranging from 2 to 17 m and circular or mainly NW-SE elongated shapes. The seismic reflection data highlight the presence of stacked buried and exposed mounds that exhibit acoustically transparent facies. They have an heterogeneous composition, mainly consisting of bioclasts of solitary scleractinians, bivalves and rhodoliths that are covered with soft sediments. These mounds may have gone through a complex mound development with a further geological and biological evolution in interaction with bottom currents. The analysis of these carbonate mounds may shed new light on the enormous scale of carbonate deposition along the Iberian Mediterranean margin, This work is a contribution to MONCARAL, funded by the Instituto Español de Oceanografia and FAUCES (CMT2015-65461-C2-R/MINECO/FEDER) projects

Simposio sobre el Margen Ibérico Atlántico (9º. 2018. Coimbra, Portugal), This work represents an approach to the more suitable proxy’s in order to identify and characterize mass movement deposits and the respective deformation. As case study was selected the Portimão Bank, a submarine E–W elongated structural high with prominent slide scars, located offshore southern Portugal in the Gulf of Cadiz. Our results show that: i) The Portimão Bank is characterized by a series of important on-going landslides; ii) The sedimentary column retrieved from piston core is replicated; iii) magnetic fabrics are able to identify a segment with approximately 90 cm that accommodated the deformation associated with the replication of the sedimentary column. Important to emphasize that such deformation goes unnoticed by mesoscopic analysis., Instituto Dom Luiz, Portugal, Instituto Superior de Engenharia de Lisboa, Portugal, Estrutura de Missão para a Extensão da Plataforma Continental, Portugal, Instituto Português do Mar e da Atmosfera, Portugal, Instituto de Ciencias del Mar, España, Centro Oceanográfico de Málaga, Instituto Español de Oceanografía, España, Instituto Geológico y Minero de España, España