Pirofanita y Braunita titánica en las rocas con Mn del Sector Central de Ossa-Morena.

• J. Jiménez Millán ^[2] ; N. Velilla ^[1]
  1. [1] Universidad de Granada

     Universidad de Granada

     Granada, España

     
  2. [2] Departamento de Geología.Universidad de Jaén.
• Localización: Geogaceta, ISSN 0213-683X, Nº. 20, 7, 1996, págs. 1542-1545
• Idioma: español
• Títulos paralelos:
  • Pyrophanite and braunite in the Mn-rocks from the Ossa-Morena Central Belt.
• Enlaces
  • Texto Completo Ejemplar
• Resumen

  • In the Oliva de la Frontera area (Ossa-Morena Central Belt, lberian Massif, SW Spain) titanian braunite occurs in manganiferous metashales and manganiferous metatuffs while pyrophanite is restricted to pyroxmangite metatuffs. During hercynian metamorphism primary Mn4+ was reduced to Mn3+ and Mn2+ to form piemontite in shales and metatuffs, and more extensively in piroxmangite metatuffs to form pyrophanite. Ti and Al-enrichment in braunite depend on the whole composition while high Fecontent in braunite of piroxmangite metatuffs can be related to low fO2 conditions.