15 documents found, page 1 of 2

Memórias da Academia das Ciências de Lisboa

Os estudos de Geomorfologia, Geologia do Quaternário e Geoarqueologia exigem idades absolutas credíveis, para: se datarem com precisão eventos sedimentares; ajudar na correlação estratigráfica; quantificar processos sedimentares; bem como para se datarem elementos de património construído ou artefactos. A determinação por luminescência e por ressonância eletrónica de spin (ESR) permite saber o momento da última...

Património geomorfológico de relevância nacional e internacional em Portugal: e...

A inventariação do património geológico constitui a base de qualquer estratégia de geoconservação e deve ser realizada com critérios objetivos, de modo sistemático e considerando todos os elementos da geodiversidade. Entre 2007 e 2012, um projeto de investigação coordenado pelo Centro de Ciências da Terra da Universidade do Minho e que contou com a parceria de outras universidades portuguesas (Aveiro, Açores, A...

Assessment of metal and metalloid contamination in the waters and stream sedime...

ABSTRACT: In the abandoned Mortórios uranium mine area there are quartz veins containing wolframite and sulphides and basic rock dykes with torbernite and autunite cutting a porphyritic granite. The basic rock dykes were exploited and produced about 27 t of U3O8, from 1982 to 1988. There are an open pit lake and nine dumps. Surface water and groundwater are contaminated in U, As, Cd, Cr, Cu, Fe, Mn, Ni and Pb. ...

Assessment of metal and metalloid contamination in soils trough compositional d...

ABSTRACT: Soils from the old Mortórios uranium mine area were studied to look for contamination, as they are close to two villages, up to 3 km away, and used for agriculture. They are mainly contaminated in U and As and constitute an ecological threat. This study attempts to outline the degree to which soils have been affected by the old mining activities through the computation of significant hot clusters, Tra...

Desacoplamento entre os setores Alto-Médio e Baixo do rio São Francisco (Brasil...

Faulted Middle Pleistocene fluvial terrace deposits at Leiria, central Portugal

Folded and faulted Middle Pleistocene terrace deposits of the Rio Lis were identified at Capuchos-Quinta de Santa Clara site, located in the city of Leiria (central-western region of mainland Portugal). These deformed sediments present a relevant assemblage of Acheulean lithic industry making them an unequivocal marker of neotectonic deformation. A detailed study of the brittle and ductile structures revealed a...

Incorporating descriptive metadata into seismic source zone models for seismic-...

In probabilistic seismic-hazard analysis (PSHA), seismic source zone (SSZ) models are widely used to account for the contribution to the hazard from earthquakes not directly correlated with geological structures. Notwithstanding the impact of SSZ models in PSHA, the theoretical framework underlying SSZ models and the criteria used to delineate the SSZs are seldom explicitly stated and suitably documented. In th...

Cenozóico das bacias do Douro (sector ocidental), Mondego, Baixo Tejo e Alvalade

Typological classification of clayey raw materials for ceramics manufacture, in...

Mapping of clay resources in the Cenozoic deposits of the Tábua 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 diff...

New seismic source zone model for Portugal and Azores for use in SHARE: methodo...