Soares, S.Dias, Ruben PereiraRessurreição, RicardoMorais, IgorAlbardeiro, LuísGonçalves, PedroSolá, A. RitaCastro-Pina, M.2023-08-042023-08-042023-07Soares, S.; Dias, Ruben Pereira; Ressurreição, Ricardo; Morais, Igor; Albardeiro, Luís; Gonçalves, Pedro; Solá, A. Rita; Castro-Pina, M. (2023) - Calcretos da região de Elvas : Estudo preliminar. In: Lopes, F. C., Dinis, P. A., Duarte, L. V. e Cunha, P. P. (Coords.). XI Congresso Nacional de Geologia: Geociências e Desafios Globais. Livro de Resumos. Coimbra, 16- 20 julho de 2023, Departamento de Ciências da Terra da Universidade de Coimbra (eds.), p. 755-756. ISBN: 978-989-98914-8-7978-989-98914-8-7http://hdl.handle.net/10400.9/4126Resumo alargadoSUMMARY: The construction of a new railway in NE Alentejo crossing the Ossa Morena Zona allowed new detailed studies focused on the geological units and the structure of the area. In the Elvas region, the Miocene is represented by a coarse conglomerate covered by sandy mudstones. The conglomerate is coarser near the Messejana fault, where it is also tilted. Its deposition is probably related to the Alpine reactivation of the fault. The sediments and the basement rocks are strongly affected by Miocene calcretization. A chemical characterization of calcrete along vertical profiles was done with portable x-ray fluorescence equipment. The preliminary results show a decrease in CaO content upwards and an increase in SiO2.porCalcreteCalcretizationGraniteConglomeratesGuadiana basinCalcretosCalichificaçãoGranitoConglomeradosBacia do Guadianaconference object