Dinámica del proceso de alteración ambiental de la «piedra de Villamayor»

• José Antonio Blanco Sánchez ^[1]
  1. [1] Geociencias. Medio-Ambiente. Unicversidad de Salamanca
• Localización: Geogaceta, ISSN 0213-683X, Nº. 6, 1989, págs. 32-35
• Idioma: español
• Enlaces
  • Texto completo (pdf)
• Resumen

  • The Villamayor sandstones, Upper Paleocene in age, are composed of strongly arkosic fluvial sediments. The sediment is organized in sequences of decreasing grain size of which only one part can de exploited for construction purposes. The principal feature of the environmental alteration of the stone is its conversion to sand which is caused by two different processes. The first is the selective hydrolysis of certain elay minerals of the cement such as chlorites and smectites. The second is the activity of precipitates of magnesium su/phate hydrated to different extents (epsomite, hexahydrite, pentahydrite and starkeyite); the annual cycle of this activity is summarized in fig. 4.