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Browsing by Author "Marques, R."

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  • Geochemistry, luminescence and innovative dose rate determination of a Chalcolithic calcite-rich negative feature
    Publication . Rodrigues, A. L.; Dias, M., I; Carlos Valera, António; Rocha, F.; Prudencio, M., I; Marques, R.; Cardoso, G.; Russo, D.
    An interdisciplinary approach comprising archaeological, chemical, mineralogical, and luminescence data was applied to a better understanding of the fill dynamic and chronologies of a calcite-rich negative archaeological feature from Southern Portugal. This work aims to contribute to the assessment of the human involvement in the backfilling actions of a negative archaeological feature from a Chalcolithic site, thus better defining the moments of its destruction and/or abandonment. There are well-known limitations of luminescence dating of calcite-rich materials, particularly in the dose rate determination. In this work, a proposal of two innovative protocols to determine the dose rate of calcite-rich contexts is discussed. A clear improvement of the dose rate estimation was obtained by using the "radionuclide weighed" protocol. The comprehensive used methodologies enabled to define the infill phases and the sources of the infill materials. The luminescence profiling studies were also useful to describe the infill processes, highlighting their discontinuity and pointing to different deposition rates. The luminescence ages obtained, when using the "radionuclide weighed" protocol proposed in this work, are closer to the archaeological evidence of a Chalcolithic occupation.
    2019-08Journal article Restricted access Show more
  • International Centre for Coastal Ecohydrology: applying the ecohydrology approach for the sustainable functioning of coastal ecosystems
    Publication . Chicharo, Luis; Ben-Hamadou, Radhouan; Araújo Amaral, Ana Margarida; Range, Pedro; Mateus, C.; Piló, David; Marques, R.; Morais, P.; Chicharo, Maria Alexandra Teodosio
    Coastal areas are among the most sensitive and productive ecosystems around the world, providing for the subsistence of large numbers of people, particularly in developing countries. Human pressure on coastal areas has dramatically increased during the last decades and climate changes will pose new threats to these areas, as expected from sea-level rise and the decrease in freshwater discharges from rivers (Chicharo et al., 2009). The International Centre for Coastal Ecohydrology (ICCE) a newly approved centre under the auspices of UNESCO, in October 2009, is located in the Algarve region (south Portugal). The centre acts as a facilitator and synergetic structure by providing the articulation of different scientific and institutional stakeholders at national and international levels. ICCE aims are to contribute scientific knowledge, capacity-building, educational and dissemination activities to support, design and implement adaptation and mitigation strategies and policies for coastal zones, including the impacts of climate change, addressing the goals of the Strategic Plan of the 7th Phase of UNESCO-IHP, the Millennium Development Goals (UN-MDGs) and the key themes for the United Nations Decade of Education for Sustainable Development (UN-DESD), particularly in African and Mediterranean regions.
    2010Conference object Open access Show more
  • Late holocene benthic Foraminifera of the Roman Lacus ligustinus (SW Spain): a paleoenvironmental approach
    Publication . Guerra, Liliana; Veiga-Pires, Cristina; Luz Gonzalez Regalado, M. L.; Abad, M.; Toscano, A.; Manuel Munoz, J. M.; Ruiz, F.; Vidal, J. R.; Caceres, L. M.; Izquierdo, T.; Carretero, M. I.; Pozo, M.; Monge, G.; Tosquella, J.; Prudencio, M. I.; Dias, M.I.; Marques, R.; Gomez, P.; Romero, V.
    This paper studies the Late Holocene benthic foraminifera from a continuous core extracted in the Doliana National Park (SW Spain). In this core, the foraminiferal assemblages confirm the Late Holocene lagoon (historically so-called Locus Ligustinus) during the Roman period, about 2000 years ago. The more open, deepest areas of this lagoon were dominated by Ammonia tepida and Elphidium spp., while Haynesina germanise was the most representative species of the shallow, more restricted zones. The vertical variations of these assemblages, together with associated sedimentological and macrofaunal changes, allow recognizing three high-energy events (HEE) between 500 BCE and 500 CE, which also left an extensive sedimentary record in nearby coastal areas: two tsunamis (HEE-1 and HEE-3) and a storminess period (HEE-2).
    2020Journal article Restricted access Show more