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- Postglacial sea-level rise in South Portugal as recorded in Guadiana EstuaryPublication . Boski, T.; Moura, Delminda; Camacho, Sarita; Duarte, Duarte; Scott, David; Veiga-Pires, C.; Pedro, Paulo; Santana, PauloThe Guadiana River Estuary is located in the terminal part of a deeply incised river valley, which accumulated several tens of meters of sediments during the Holocenic transgression. Five cored boreholes (see Fig.1 for localisation) that reached the pre-Holocenic substratum were drilled recently in order to recognize the architecture of sedimentary facies and to quantify the accumulation of organic carbon trapped in sediments during the valley infilling by marine waters. It was assumed that due to structural constraints imposed by Palaeozoic and Mezozoic substratum, the main estuarine channel did not change its position significantly. Consequently borehole locations were chosen in order to represent different sedimentary environments in the estuary: proximity to the main channel (CM1 and CM3), external sea facing (CM4) and lagoonal (CM2 and CM5) environments.
- Preenchimento sedimentar em três estuários do Algarve durante o HolocénicoPublication . Boski, T.; Moura, Delminda; Veiga-Pires, C.; Duarte, Duarte; Santana, Paulo; Pedro, PauloAs bacias hidrográficas são distintas quer do ponto de vista hidrológico quer na forma e àrea de captação.
- A subida do nível do mar durante o Holocénico no Golfo de Cadiz – tendência regional e diferenças locaisPublication . Moura, Delminda; Boski, T.; Duarte, Duarte; Veiga-Pires, C.; Pedro, Paulo; Lourenço, Nuno; Diniz, FilomenaIn Guadiana River Estuary, the Holocene sequence is underlain by pebbly delta fan formed in two stages, prior to 5E and 3 highstands. The Holocene sedimentary sequence was lain either directly on gravels or on top of fluvial sands deposited between 11000 and 10000 yr. BP. An accelerated phase of infilling of the estuary by clayey sediments, containing marsh foraminifer Trochammina, began at ca. 9800 yr. BP when the sea level was about 39 m below the present.At ca. 7000 BP the central part of the estuary started to accommodate coarser sediments, partially introduced from the shelf. The first phase of the Holocene sea level rise at a rate of 0.85 m/century terminated at ca 6500yr. BP. Since then, the lagoonal bodies in the vicinity of estuary started to enclose behind sand spits and predominantly sandy sedimentation initiated within the estuary. After the second phase of a slower rise at the rate of 0.3 m/century, which lasted until ca. 5000 yr.BP, the sea approached the present level. Data from Guadalete Estuary published in Spain set the beginning of Holocene transgression at shallower level (ca 10m)than in Guadiana Estuary.This discrepancy may be explained by isostatic uplift of Betic Cordillera or slumping of Guadiana terrace on which the Holocene sediments are lain. Since 7500 yr. BP the data from Odiel-Tinto, Guadalete and Guadiana are in a relatively good agreement.