http://digital.csic.es/bitstream/10261/49073/1/CanC_review_PiO2009.pdf

Sub-regional ecosystem variability in the Canary Current upwelling

http://digital.csic.es/bitstream/10261/50292/1/Physical_oceanography_western_Iberia.pdf

Physical oceanography of the western Iberia ecosystem: Latest views and challenges

An overview of the winter circulation and upper ocean structure offshore of Western Iberia is presented. The focus is on winter slope currents, fronts and mesoscale eddies, as well as on the connection of these local features to the large-scale circulation of the region. Satellite sea surface temperature; sea surface elevation data from altimetry; cross-shore and meridional hydrological surveys and current meter observations, mainly obtained during winter periods, are used to illustrate features of the winter upper ocean structure and of the generation and evolution of the Iberia Poleward Current. A schematic/hypothetical model of winter upper ocean circulation on the scale of the Western Iberian Basin is given which attempts to systematize and resolve certain ambiguities in the existing circulation schemes and in the concepts and terminology used to describe observed features in the area.

Winter upper ocean circulation in the Western Iberian Basin—Fronts, Eddies and Poleward Flows: an overview

Present-day and past (last 25000 years) marine pollen signal off western Iberia

The aim of this work is to constrain the provenance and depositional history of continental slope sediments in the Southwestern Gulf of Mexico (~1089–1785 m water depth). To achieve this, 10 piston sediment cores (~5–5.5 m long) were studied for mineralogy, major, trace and rare earth element geochemistry. Samples were analyzed at three core sections, i.e. upper (0–1 cm), middle (30–31 cm) and lower (~300–391 cm). The textural study reveals that the core sediments are characterized by silt and clay fractions. Radiocarbon dating of sediments for the cores at different levels indicated a maximum of ~28,000 year BP. Sediments were classified as shale. The chemical index of alteration (CIA) values for the upper, middle, and lower sections revealed moderate weathering in the source region. The index of chemical maturity (ICV) and SiO 2 /Al 2 O 3 ratio indicated low compositional maturity for the core sediments. A statistically significant correlation observed between total rare earth elements (∑REE) versus Al 2 O 3 and Zr indicated that REE are mainly housed in detrital minerals. The North American Shale Composite (NASC) normalized REE patterns, trace element concentrations such as Cr, Ni and V, and the comparison of REE concentrations in sediments and source rocks indicated that the study area received sediments from rocks intermediate between felsic and mafic composition. The enrichment factor (EF) results indicated that the Cd and Zn contents of the upper section sediments were influenced by an anthropogenic source. The trace element ratios and authigenic U content of the core sediments indicated the existence of an oxic depositional environment.

Provenance and depositional history of continental slope sediments in the Southwestern Gulf of Mexico unraveled by geochemical analysis

Mapping of clay resources in the Cenozoic deposits of the Tabua region (central Portugal) has been carried out, together with the chemical, mineralogical and technological characterization of seventeen clay samples. The study was undertaken to relate the lithostratigraphic units and the typology of raw materials with regard to the manufacture of ceramics. The sedimentary succession comprises two units with different suitability for the manufacture of ceramics: an upper unit, with clays that present technological restrictions; and a lower unit with a much greater potential. A small set of parameters has been identified which differentiate the typological units. These parameters allow a realistic estimation to be made of the ceramic properties of any clay layer sampled in the study area. It is anticipated that with minor field work and sampling, the typological column can also be used in adjacent areas.

/pdf/typological-classification-of-clayey-raw-materials-for-7z0035v6up.pdf

Typological classification of clayey raw materials for ceramics manufacture, in the Tabua region (central Portugal)

Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal Faculdade de Ciencias e Tecnologia, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal Instituto Portugues do Mar e Atmosfera (IPMA), Av. 5 de Outubro, 8700-305 Olhao, Portugal Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar Instituto Portugues do Mar e Atmosfera (IPMA), Av. Brasilia, 1449-006 Lisbon, Portugal CIIMAR – Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas 177, 4050-123 Porto, Portugal Centro de Investigacao Marinha e Ambiental (CIMA) Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal

/pdf/relative-sensitivity-of-soft-bottom-intertidal-macrofauna-to-5dle0wetr1.pdf

Relative sensitivity of soft-bottom intertidal macrofauna to increased CO2 and experimental stress

Assessment of organic matter preservation and coastal constraints (SE Algarve, Portugal)

Submarine canyons are deep and steep incisions on the continental margins. The physical forcing mechanisms linked with these marine systems, such as the enhancement of upwelling and bottom sediment resuspension, are expected to provide a nutrient source that will increase phytoplankton density (Hickey, 1995, Kampf,2006). Coccolithophores are the predominant phytoplanktonic group within the calcareous nannoplankton and their sensitivity to a variety of surface water environmental parameters makes them important markers of oceanographic processes and proxies of sea surface water masses and temperatures, productivity and past climate changes (e.g. Ziveri et al., 2004; Silva et al., 2008). In the present work we propose to test compositional analysis (Buccianti & Esposito, 2004; Pawlowsky-Glahn & Egozcue, 2006) as a tool to: a) achieve a clearer distinction between opportunistic coastal-neritic species (r-strategists) and typical oceanic species (k-strategists) in the central Portuguese margin, and b) to identify a coccolith assemblage that might reflect favorable environmental conditions found in the vicinity of the canyon that promotes the productivity of calcareous nannoplankton. Our main difficulty will be in distinguishing the ecological signal from the effects of other environmental factors mentioned before (i.e. advection, dissolution, bottom resuspension). One way to infer the species’ ecological inter-relationships is by determining species relative percentages. The main concern is how the closure problem and the inconsistency of percentage determinations will affect our results. Compositional analysis was designed to provide more reliable and thus representative results, since the inference made on the coccolith assemblage features from which the data are drawn is correctly performed from a theoretical point of view (Buccianti & Esposito, 2004). Here, we present the first insights from applying compositional data analysis to coccolith assemblages from 85 surface sediment samples collected from the central Portuguese margin.

Compositional Data Analysis as a Potential Tool to Study the (Paleo)ecology of Calcareous Nannoplankton from the Central Portuguese Submarine Canyons(W off Portugal)

The geochemistry of Pliocene muddy sediments is determined to address the main phases that carry the rare earth (REE). Three different facies, related to floodplain and swamp-lake deposition, and two sectors were considered. It was found that the heavy REE concentration is substantially higher in swamp-lake than in floodplain sediments. Though clay minerals host part of the REE, xenotime and monazite must be the main carrying minerals. Other phases (e.g. organic matter) in swamp-lake facies must retain an important part of the REE, in particular the heavy REE. The REE concentrations in the two sectors are not substantially different, suggesting that provenance was similar.

Terras raras nos sedimentos Pliocénicos entre os rios Vouga e Mondego (Portugal) = Rare earth elements in the Pliocene sediments between rivers Vouga and Mondego (Portugal)

Álvaro Oliveira

Papers

Typological classification of clayey raw materials for ceramics manufacture, in the Tabua region (central Portugal)

Relative sensitivity of soft-bottom intertidal macrofauna to increased CO2 and experimental stress

Assessment of organic matter preservation and coastal constraints (SE Algarve, Portugal)

Compositional Data Analysis as a Potential Tool to Study the (Paleo)ecology of Calcareous Nannoplankton from the Central Portuguese Submarine Canyons(W off Portugal)

Terras raras nos sedimentos Pliocénicos entre os rios Vouga e Mondego (Portugal) = Rare earth elements in the Pliocene sediments between rivers Vouga and Mondego (Portugal)