Litologías manganesíferas del área central de Ossa-Morena (SW de Badajoz)

  1. Jiménez Millán, Juan
  2. Ruiz de Almodóvar Sel, Gabriel
  3. Velilla, Nicolás
Revista:
Geogaceta

ISSN: 0213-683X

Año de publicación: 1992

Número: 12

Páginas: 46-49

Tipo: Artículo

Otras publicaciones en: Geogaceta

Resumen

Mangenese lithologies from Oliva de la Frontera area occur in the Cumbres-Hinojales unit (Ossa-Morena South-Central Belt) within a Lower Ordovician age volcanosedimentary sequence. Petrographic study allows to differentiate six Mn-Fe lithologies: Mn-crystal tuffs, Mn-shales, cotfcules, Mn-pyroxenoid rich rocks, braunite layers and hematite layers. Al/(Al+Fe-f-Mn) and Na/(Na+K) discriminating ratios support the above classification. Geologic, mineral, textural and geochemical data provide dues about the mixture process among volcanic, terrigene and chemical materials that originated the protolliths o f the metamorphic manganese lithologies