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- The example of the Quartzite from the "Upper Quartzite Formation", "Trás-os-Montes e Alto Douro" (NE Portugal). Its characterization as natural stone for constructionPublication . Aires, Sílvia; Noronha, Fernando; Carvalho, Cristina Isabel Paulo; Moura, A. Casal; Ramos, João Farinha
- Eucisia schist a natural stone from Northern PortugalPublication . Aires, Sílvia; Carvalho, Cristina Isabel Paulo; Noronha, Fernando
- "Schist" from "Trás-os-Montes e Alto Douro" (NE Portugal) - Potential use as Natural StonePublication . Carvalho, Cristina Isabel Paulo; Aires, Sílvia; Noronha, Fernando; Moura, A. Casal; Ramos, João Farinha
- Os xistos do "Complexo Xisto-Grauváquico - Grupo do Douro" : potencial como recurso geológicoPublication . Aires, S.; Carvalho, Cristina Isabel Paulo; Noronha, Fernando; Ramos, João Farinha; Moura, A. Casal; Sant'Ovaia, Helena; Sousa, M.O trabalho desenvolvido no projecto I&D financiado pela FCT contribuiu para o aumento do conhecimento dos recursos geológicos de Trás-os-Montes e Alto Douro (TOM-AD), em particular dos "XISTOS", através da sua caracterização geológica, petrográfica, química e físico-mecânica. Nesta contribuição apresentamos o exemplo do estudo das explorações do Complexo Xisto-Grauváquico - Grupo do Douro: Eucísia, Nozelos, Tanha e Poio. A utilização destas rochas poderá dar um contributo positivo às condições sócio-económicas nesta região.
- Natural stone from the Azores archipelago : relationship between lithology and physical-mechanical behaviourPublication . Silva, João B. P.; Carvalho, Cristina Isabel Paulo; Caetano, Sérgio Diogo; Gomes, Celso
- Natural Stones from Portugal : Proposal for harmonizing Commercial NamesPublication . Carvalho, Jorge; Carvalho, Cristina Isabel Paulo; Lopes, Luis; Silva, António; Santos, Catarina; Sousa, Luís; Martins, Ruben; Marques, CéliaABSTRACT: Over the years, the Portuguese Geological Survey – LNEG, has been dedicated to the characterization of Portuguese natural stones. Today, a newly updated LNEG web portal contains information on 149 natural stones, which are known by their unique trade names. Many of these names integrate the EN 12440 - Natural Stone - Denomination Criteria standard, but others do not. Furthermore, there many other names used to identify natural stones that are traded today and that do not integrate the LNEG web Portal or the EN 12440. This work presents a harmonization proposal for the commercial denomination of the Portuguese natural stones. It is a working basis for a final list that must be submitted to ISO/Technical Committee 118 – Natural Stones.
- "Schist" as a geological resource of "Trás-os-Montes e Alto Douro" (NE Portugal)Publication . Noronha, Fernando; Carvalho, Cristina Isabel Paulo; Aires, Sílvia; Moura, A. Casal; Ramos, João Farinha
- Depth estimation of pre-Kalahari basement in Southern Angola using seismic noise measurements and drill-hole dataPublication . Carvalho, João; Alves, Daniela; Borges, José Fernando; Caldeira, Bento; Cordeiro, Domingos; Machadinho, Ana; Oliveira, Álvaro; Ramalho, Elsa; Rodrigues, José Feliciano; Llorente, J.; Ditutala, M.; Lobón, Jose Luis Garcia; Máximo, J.; Carvalho, Cristina Isabel Paulo; Labaredas, José; Ibarra, P.; Manuel, JoséABSTRACT: The remote Southern region of Angola is covered by siliciclastic Kalahari Cenozoic formations that host underground aquifers of great importance to local populations affected by water scarcity problems. These aquifers are well developed where Kalahari sands reach appropriate thicknesses. On the other hand, at the eastern end of this area, regional aeromagnetic data recently acquired suggested the possibility of the continuity of the geological structures of the Lufilian Arc, sited in the nearby Zambia and Congo, southwestwards into Angola under the Kalahari formations. Once the Lufilian Arc is associated with the presence of the so-called Central African Copperbelt, this possibility increased the interest in determining the depth to Pan-African rocks under the Kalahari basin. To estimate the thickness of Kalahari formations in this area of difficult access and poor logistics, an expedited and non-invasive geophysical method was needed. Seismic noise and the single-station Nakamura technique were chosen, but due to the large distance of the study area from the ocean, one of the major sources of seismic noise, a test survey was acquired in the Cuvelai region to assess the signal quality, where the data was calibrated using available drill-holes. >170 points of seismic ambient noise were later acquired and the horizontal/vertical (HVSR) amplitude versus frequency curves were 1D inverted for the best velocity/density model for each station. The results were compared with 1D inverted legacy vertical electrical soundings reprocessed and validated in this work, showing similar depth-to-basement, while interpreted velocities/densities of geological formations were sampled and confirmed with measurements. A depth-to-basement map was produced using seismic information, mechanical soundings, and geological information. Despite the relatively reduced geographical area covered, the map presents valuable information for hydrogeology and mineral exploration purposes and agrees with a previously available coarser map of Kalahari thickness and with observations from geological surveys simultaneously conducted at the time of the seismic surveys.
- Influência da resistência ao gelo de rochas silicatadas portuguesas na utilização como elemento construtivo exteriorPublication . Borges, Maria Isabel; Simão, J.; Carvalho, Cristina Isabel Paulo; Pires, Vera
- Portuguese ornamental stonesPublication . Carvalho, Jorge; Carvalho, Cristina Isabel Paulo; Lisboa, Jose; Moura, A. Casal; Machado Leite, Mário
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