RT Journal Article T1 Análisis de los procesos de formación de minerales de la unidad de arcosas de la cuenca del tajo A1 Domínguez Díaz, M. C. A1 Doval, M. A1 García Romero, E. A1 Brell, J. M. AB A mineralogic study of the Tajo Basin's Arcoses Unit has been realized from borehole's data. The mineralogy of these sediments corresponds mainly to in herited phases resulting from alteration of granite.Biotite and muscovite micas are transformed to smectites (ferriferous beidellites and to a lesser extent montmorillonites), mixed-layer l-Sm and illites, at the source area. Feldspars alter mainly to dioctahedrical smectites an minor kaolinite. Electronic microscopy observations of micas transforming to illite-smectite and the presence of mixed-layer Cl-Sm, suggest that part of the transformations continued within the basin after sedimentation PB Sociedad Geológica de España YR 1996 FD 1996 LK http://hdl.handle.net/10272/12933 UL http://hdl.handle.net/10272/12933 LA spa DS Repositorio Institucional de la Universidad de Huelva RD 31 may 2026